Re: Topband: B7P

[Michael Tope]

I have a 402CD ready to go once I get another tower up. We'll see how 
that works :-)


73, Mike W4EF.

On 4/4/2024 10:57 AM, jim.thom jim.t...@telus.net wrote:

Date: Wed, 3 Apr 2024 22:07:33 -0700
From: Michael Tope
To:topband@contesting.com
Subject: Re: Topband: B7P



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Re: Topband: B7P

[Michael Tope]

That sure seems to be the case, Bob. Heck even on 40 meters I have found 
myself calling loud Chinese stations in vein. My dipole at 45ft just 
doesn't cut it. It must be that there aren't very many BY hams that live 
in rural areas with low noise floors. Hopefully portable operations with 
verticals on the beach will catch on there.


Somewhere I have a recording of WA6TQT running stations during the CQ WW 
160 SSB contest from the old W6BH mountaintop super-station near Anza, 
CA. I was surprised to hear a couple of Europeans call him that I could 
actually hear Q5. It was quite a thrill. Conditions must have been very 
good that evening.


73, Mike W4EF...



On 4/3/2024 8:13 AM, w3...@roadrunner.com wrote:

Great to hear ur recording of B7P on 160m popping thru the noise, even
if I am 2500 miles further east Hi Hi.

This thread implies that Life in China comes with huge QRM-powerline
noise, which makes a lot of sense. So the Chinese ops flock to 10m.
Most of the ones I worked with my home brew Moxon at 22 ft were
peaking 59 and in some cases even stronger during a 15-30 minute
window post- Ohio sunset.



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Re: Topband: Any Chinese stations with Big Sigs operating on 160?

[Michael Tope]

In the case of that 160 meter dipole it was almost always better as a 
receive antenna for 80 meters. It was better at rejecting ferocious 
local QRN than the 80 meter inverted-V. Absolute signal level always 
dropped owing to the mismatch, but the noise level dropped even more 
improving SNR (from really deaf to pretty deaf). I am sure there were 
cases where the 80 meter inverted-V was better, but that was the 
exception not the rule.


I agree that Ken has the nice problem of having lots of antennas to 
chose from for RX :-)


73, Mike W4EF


On 4/3/2024 2:20 AM, Jim Brown wrote:
At N6RO's superstation (among other things, it was the antenna labo of 
ARRL Antenna Book Editor N6BV, who lives 100 miles away in the city of 
San Francisco), Ken patches lots of antennas to his operating position 
for 160M contests for use as RX antennas. The reason is simple -- the 
elevation, and even the horizontal direction at which signals arrive 
can vary widely with time, based on propagation.  Ken is a very smart 
engineer, and a bunch of very smart engineers and operators are on his 
team.


73, Jim K9YC


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Re: Topband: Any Chinese stations with Big Sigs operating on 160?

[Michael Tope]

I just occurred to me that my description of the receive situation at 
W6UE is backwards. The 160 meter flat top dipole improved the 80 meter 
receive noise floor from really deaf to pretty deaf. On 160 meters we 
were just really deaf whether we listened on the 160 meter dipole or the 
80 meter inverted-vee :-)


73, Mike W4EF..

On 4/2/2024 6:03 PM, Michael Tope wrote:
When we tried operating in 160 meter contests from W6UE in Pasadena, 
it was amusing to see the packet spots complaining about how deaf we 
were. We were running a full size flat-top dipole at 90 feet. It 
apparently worked pretty well as a transmit antenna. Using the 80 
meter inverted-vee for receive that was off the same 90 foot apex at 
more or less a right angle to the dipole actually improved things 
significantly (e.g. from really deaf to pretty deaf).


Here is an iPhone video of a Q5 "speaker copy" B7P calling CQ on 160 
meters during the 2022 CQ WW SSB contest. I tried calling them (off 
the video) with no luck whatsoever. I don't think they worked any 
North Americans. By contrast, during the 2024 ARRL SSB contest, JA3YBK 
who was also Q5 speaker copy came right back to me on the first call 
(I don't think I have a recording of that QSO):


https://www.dropbox.com/scl/fi/kd2euhx7x5a5dd5iatm7c/B7P-2022-CQ-WW-SSB-160M.mp4?rlkey=xd6qpj5d3ikg2u39fvotheqhz=0 



73, Mike W4EF...

On 4/2/2024 3:12 PM, Jim Brown wrote:

On 4/2/2024 2:45 PM, David Raymond wrote:

Yes, the Chinese have really discovered ham radio in the last decade.


And beginning 6-8 years ago, they figured out that they had to set up 
stations where the noise was low enough that they could hear stations 
calling them. When they first appeared, the noise made them deaf. No 
different from here in NA.


73, Jim K9YC





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Re: Topband: Any Chinese stations with Big Sigs operating on 160?

[Michael Tope]

When we tried operating in 160 meter contests from W6UE in Pasadena, it 
was amusing to see the packet spots complaining about how deaf we were. 
We were running a full size flat-top dipole at 90 feet. It apparently 
worked pretty well as a transmit antenna. Using the 80 meter 
inverted-vee for receive that was off the same 90 foot apex at more or 
less a right angle to the dipole actually improved things significantly 
(e.g. from really deaf to pretty deaf).


Here is an iPhone video of a Q5 "speaker copy" B7P calling CQ on 160 
meters during the 2022 CQ WW SSB contest. I tried calling them (off the 
video) with no luck whatsoever. I don't think they worked any North 
Americans. By contrast, during the 2024 ARRL SSB contest, JA3YBK who was 
also Q5 speaker copy came right back to me on the first call (I don't 
think I have a recording of that QSO):


https://www.dropbox.com/scl/fi/kd2euhx7x5a5dd5iatm7c/B7P-2022-CQ-WW-SSB-160M.mp4?rlkey=xd6qpj5d3ikg2u39fvotheqhz=0

73, Mike W4EF...

On 4/2/2024 3:12 PM, Jim Brown wrote:

On 4/2/2024 2:45 PM, David Raymond wrote:

Yes, the Chinese have really discovered ham radio in the last decade.


And beginning 6-8 years ago, they figured out that they had to set up 
stations where the noise was low enough that they could hear stations 
calling them. When they first appeared, the noise made them deaf. No 
different from here in NA.


73, Jim K9YC





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Re: Topband: https://clublog.org/logsearch/CB0ZA

[Michael Tope]

Yeah, I suppose you could do that for "N-band DXCC" as well. It already 
exists for DXCC Honor Roll tallies.


73, Mike W4EF.

On 2/19/2024 3:32 PM, Steve Harrison wrote:

On 2/19/2024 3:25 PM, Michael Tope wrote:

Since reclassifying 160 DXCC totals to exclude FT8 would be terribly
unfair to those who submitted FT8 confirmations toward DXCC in good
faith, it seems like a possible solution would be to add provisions
for a CW endorsement to the 160 meter DXCC award. If it were workable
administratively, it would provide a way for those who made the
majority of their DXCC contacts on CW to compare themselves with
others who have done similarly. It would also provide a way for those
who enjoy FT8 to compare their progress with others in the "unlimited"
category. Who knows, it might even encourage a resurgence of CW
activity, since that endorsement would carry a certain cache.


Make such a CW endorsement for ALL bands.

Steve, K0XP



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Re: Topband: https://clublog.org/logsearch/CB0ZA

[Michael Tope]

Since reclassifying 160 DXCC totals to exclude FT8 would be terribly 
unfair to those who submitted FT8 confirmations toward DXCC in good 
faith, it seems like a possible solution would be to add provisions for 
a CW endorsement to the 160 meter DXCC award. If it were workable 
administratively, it would provide a way for those who made the majority 
of their DXCC contacts on CW to compare themselves with others who have 
done similarly. It would also provide a way for those who enjoy FT8 to 
compare their progress with others in the "unlimited" category. Who 
knows, it might even encourage a resurgence of CW activity, since that 
endorsement would carry a certain cache.


73, Mike W4EF

On 2/19/2024 1:51 PM, Wes Stewart via Topband wrote:

  It is unreasonable to assume all FT8 QSOs are with robots, however, many are.  Technically, some 
"I" (my computer) makes are made with me not in attendance.  When I can disable transmit 
and walk out to the kitchen to get another beer and come back to see that my software has tuned my 
radio to the Fox frequency and called him to complete the QSO, I think that's a "robot."
And that is exactly why I do not submit WSJT contacts for DXCC credit.  If others want 
to, that's between them and their ethics.  Why do I make the contacts then? you may ask. 
Because one of my DX clubs has an internal competition where certain expeditions are 
designated as targets for "band slot Bingo", where we compete for the greatest 
number of slots worked.  You can't win if you don't play.
As to efficiency, I think FT8 wastes a lot of time.  Other modes, including RTTY, are 
simply faster, although they require more operator skill on both ends.  F/H is 
particularly bad in this regard.  You can call and call and might actually be in the 
queue but not know it until you go to the kitchen for that beer and come back and see 
that "you" made the contact.
Another particularly distasteful thing about FT8 is that the DX can set filters 
to exclude certain callers based on signal strength, distance, country, etc. 
and the callers never know it.  I know there will be vehement denial of this 
but I know it happens.
WSJT will never replace RTTY.

 On Monday, February 19, 2024 at 12:56:59 PM MST, Jim Brown 
 wrote:
  
  On 2/19/2024 7:27 AM, Saulius Zalnerauskas wrote:

Look's like this "Sherlock Holmes" not understand what CB0ZA Robot doing.

It is unreasonable to assume that all FT8 QSOs are with robots. I know
some of the very experienced CW ops who run FT8 on expeditions. WSJT-X
software makes the mode quite time-efficient for expeditions. It's a
replacement for RTTY, not CW.
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Re: Topband: remotes

[Michael Tope]

Yes, it think it is possible to compete with yourself even in a sport 
like boxing. The point is that not everyone is going to be Mike Tyson or 
Mohammad Ali. That doesn't mean that you don't strive to win. It means 
that you put losing to a better fighter in perspective. You train hard, 
work on improving your skills, and measure your success based on how you 
measure up to older versions of yourself. Winning a fight is just icing 
on the cake.


73, Mike W4EF..

On 2/6/2024 7:04 AM, uy0zg via Topband wrote:


The original idea is to compete with yourself..

In this case, there is no need to summarize the results of the 
contests...


I wonder, is it also possible to compete with yourself in boxing? :-(


---
Nick, UY0ZG
http://www.topband.in.ua

Michael Tope писал(а) 2024-02-06 16:42:
People are driven by different things. For instance, I would be lying 
if I claimed I wasn't competitively driven. And I can tell you that 
at points in my life it has caused me to "lose perspective". Have I 
been overly enthusiastic with the drive to my Alpha 91 amplifier on 
occasion? Yes. Have I driven like an idiot in the wee hours of the 
morning in hope of getting to my station in time to work a new one? 
Yes. For some folks, their narcissism seems to be so bad that there 
are no lines they won't cross to be able to claim top-dog status 
(e.g. Europeans using North American remotes to work new ones on 160, 
claiming to be unassisted in contests while using DX cluster 
assistance, etc).


I think the best advice I've ever heard in this regard is to compete 
with yourself instead of competing with others. For instance, I can 
almost guarantee that I will never make top 10 in the CW Sprint 
contest. I can, however, try to best my previous scores (and 
hopefully stave off cognitive decline). Push yourself to be a better 
operator and/or station builder, use the accomplishments of your 
betters to show you what is possible, take pride in your 
accomplishments, enjoy the thrill of rare openings, and first and 
foremost - have fun!


73, Mike W4EF...


On 2/6/2024 5:39 AM, uy0zg via Topband wrote:
But in reality everything is much more complicated. We talked here 
in the reflector and went our separate ways..

For example, someone on this list honestly earned 300 countries :

http://www.arrl.org/system/dxcc/view/DXCC-160M-20240206-USLetter.pdf

He's been working on this for decades. And suddenly some completely 
unfamiliar and envious mug without RX antennas (and maybe without a 
station at all) declares 320...


Calling it simply injustice is not enough...


309
UT5UGR
W3GH*
308
I4EWH
IV3PRK
K8GG
SM6CVX
W5IZ
307
DJ7MI
IK4MGP
K4SV
OH5VT
RZ3AM
UT3UA
VE3EJ


---
Nick, UY0ZG
http://www.topband.in.ua

Mike Smith VE9AA писал(а) 2024-02-06 14:51:
I knew it was all over many years ago when I worked a 20dB/9 
Italian station

around Sunrise here in one 160m contest. (1pm in Italy)



I have never applied for DXCC.  I know what I worked and keep track 
of it

here locally.  I am the only person who really

cares what all the numbers are and since the ARRL DXCC program has 
(imo)
become so watered down in the last couple decades there is little 
reason to

ever apply.



Be happy with who you see in the mirror every morning and celebrate 
those
around you who are doing it the way that appeals to you. For those 
that
aren't.well, don't concern yourself with them.  They don't diminish 
what

you've done.



73 Mike VE9AA



Mike - Keswick Ridge, NB, Canada



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Re: Topband: remotes

[Michael Tope]

People are driven by different things. For instance, I would be lying if 
I claimed I wasn't competitively driven. And I can tell you that at 
points in my life it has caused me to "lose perspective". Have I been 
overly enthusiastic with the drive to my Alpha 91 amplifier on occasion? 
Yes. Have I driven like an idiot in the wee hours of the morning in hope 
of getting to my station in time to work a new one? Yes. For some folks, 
their narcissism seems to be so bad that there are no lines they won't 
cross to be able to claim top-dog status (e.g. Europeans using North 
American remotes to work new ones on 160, claiming to be unassisted in 
contests while using DX cluster assistance, etc).


I think the best advice I've ever heard in this regard is to compete 
with yourself instead of competing with others. For instance, I can 
almost guarantee that I will never make top 10 in the CW Sprint contest. 
I can, however, try to best my previous scores (and hopefully stave off 
cognitive decline). Push yourself to be a better operator and/or station 
builder, use the accomplishments of your betters to show you what is 
possible, take pride in your accomplishments, enjoy the thrill of rare 
openings, and first and foremost - have fun!


73, Mike W4EF...


On 2/6/2024 5:39 AM, uy0zg via Topband wrote:
But in reality everything is much more complicated. We talked here in 
the reflector and went our separate ways..

For example, someone on this list honestly earned 300 countries :

http://www.arrl.org/system/dxcc/view/DXCC-160M-20240206-USLetter.pdf

He's been working on this for decades. And suddenly some completely 
unfamiliar and envious mug without RX antennas (and maybe without a 
station at all) declares 320...


Calling it simply injustice is not enough...


309
UT5UGR
W3GH*
308
I4EWH
IV3PRK
K8GG
SM6CVX
W5IZ
307
DJ7MI
IK4MGP
K4SV
OH5VT
RZ3AM
UT3UA
VE3EJ


---
Nick, UY0ZG
http://www.topband.in.ua

Mike Smith VE9AA писал(а) 2024-02-06 14:51:
I knew it was all over many years ago when I worked a 20dB/9 Italian 
station

around Sunrise here in one 160m contest. (1pm in Italy)



I have never applied for DXCC.  I know what I worked and keep track 
of it

here locally.  I am the only person who really

cares what all the numbers are and since the ARRL DXCC program has (imo)
become so watered down in the last couple decades there is little 
reason to

ever apply.



Be happy with who you see in the mirror every morning and celebrate 
those

around you who are doing it the way that appeals to you.  For those that
aren't.well, don't concern yourself with them.  They don't diminish what
you've done.



73 Mike VE9AA



Mike - Keswick Ridge, NB, Canada



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Re: Topband: VK/ZLs in the CQWW CW 160?

[Michael Tope]

ZL3IO spotted me Saturday night (Sunday UTC) at 0728 UTC, but I never 
heard him call me. If he did call me, it could be that I had my SAL-30 
pointed NE at the time. It doesn't have the greatest RDF, but it does 
have a really high F/B. After I saw the spot, I listened to the SW, but 
I didn't hear anything.


73, Mike W4EF.

On 1/29/2024 7:19 AM, Tree wrote:

"Didn't hear any VKs or ZLs during the contest; were any of you on??"

There were - but sometimes, they go to bed after listening to summer time
QRN and aren't on the band during the best time for the West Coast.

Sometimes, you are more likely to work a VK6 than a ZL or VK3 since the
times line up better.

VK2GR made 57 QSOs, mostly Europe.  He worked a handful of stateside
stations, but pulled the plug at 1028, which is way too early for optimum
propagation to the West Coast.

VK2PW made about 21 QSOs, mostly Europeans, a few Asians and no stateside
QSOs (was active around noon your local time).

VK3IO was also active, only working ZL3IO during the time it was dark on
the West Coast - and working about 20 Europeans.

You might remember VK6GX was only able to work one station in the recent
Stew Perry.  This was right at my sunrise.

ZL3IO made 38 QSOs and reports in his soapbox that this must have been one
of the worst CQ 160 contests ever.  He did manage to work 13 stateside
stations, but only ND7K and NA7TB on the west coast.  He was QRT by 1148
UTC.

It's a tough band down under in the middle of summer.  I have spent many an
hour trying to hear a VK who is working the East coast.  After sunrise in
the midwest, there is a whole swath of the country without much activity
and it gets - dare I say - boring waiting for the sunrise on the west
coast.  It's late - they are tired and time to go to bed so they can get up
for the morning sunrise opening to Europe, which is often more reliable.

Tree N6TR





On Mon, Jan 29, 2024 at 6:15 AM Steve Harrison  wrote:


Didn't hear any VKs or ZLs during the contest; were any of you on??
There was a decent opening toward SE Asia Sunday (Monday, your time, I
suppose) morning with lots of JAs, a very strong HL5IVL plus a few DSes,
a few middling-strength BYs (none workable), half a dozen YB/YCs plus
7D1C on Sunday morn your time, XVs both mornings; but no VK/ZLs  8-(

Steve, K0XP



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Re: Topband: CONDX CQWW DR5X

[Michael Tope]

There was an insanely good opening from here in Southern California to 
Europe this evening (Sunday UTC) starting around 0600 UTC. It lasted a 
little over 15 minutes. Signals were Q5 and stations came back to me on 
the first or second call. It was surreal. I worked 8 European stations, 
all new multipliers, in that short period. I've experience openings like 
this to Europe before, but I don't think I've ever experienced one this 
good in the middle of CQ 160. When the opening ended, it was like 
someone flipped a switch and conditions were back to normal.


I should say that I was lucky to be operating in the assisted category. 
I stumbled on to the first station European station while tuning and 
then I started clicking on spots to work the rest. And to think I almost 
opted to take a nap before the opening.


73, Mike W4EF..



On 1/27/2024 10:25 AM, Andree DL8LAS via Topband wrote:

Hey topbanders,during first night CQWW 160m I worked 110 stations NA , also 
west coast .Condx were not bad here in DL.Hope to work more DX tonight.
73 Andy DL8LAS / DR5X

www.dl8las.com
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Re: Topband: Inverted-L question

[Michael Tope]

Remember, Steve, for a given frequency more capacitance equals less 
capacitive reactance [Xc = 1/(2*pi*f*c)]. At 1825 KHz, 5300 pf is only 
16.5 ohms reactance. That means you are only offsetting a small amount 
of inductive reactance. Where you should be more concerned is when the 
series capacitance is very small. That is when capacitive reactance (Xc) 
gets large and the RF voltage across the series capacitor can get very 
high.


73, Mike W4EF..

On 12/20/2023 5:43 PM, Steve Muenich wrote:

I have an Inverted-L question that hopefully someone can answer for me.

I  installed the 160m  wire to the 80 ft level on a 100 ft Rohn 45 tower
with top mounted yagis.
The horizontal (sort of) portion is approx 45ft long.
The wire starts at 80 ft down approx 5 ft from tower and when it gets to
the match box the bottom of the wire is about 10ft away from tower.

I have about 50 or so 120 ft long radials.

I am able to get a X=0, R=52. SWR 1.19:1 tune according to my RE Zoom using
load shunt match at base of tower.

My question is why do I need so much series capacitance (5300pf) with
parallel inductance approx 8uh?

Everything is working fine, but I am wanting to understand why I am needing
so much series capacitance? Does this indicate an issue I need to resolve?

TIA,

Steve, NA5C
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Re: Topband: Timor Leste report #8

[Michael Tope]

Interestingly, conditions on the west coast seemed pretty good this 
morning around our sunrise. I was able to decode HS5NMF between -8 and 
-5 and 9M6NA got as high as +1. I suspect both could have been heard 
reasonably well on CW. OTOH, the QRN level on their end might have 
precluded 2-way contacts.


Thank you for your efforts to keep CW alive on Topband, Dietmar. I do 
operate FT8. It does seem to make contacts possible that would not be 
possible on CW (all other things being equal), but I don't find it 
nearly as satisfying as a good CW contact.


73, Mike W4EF..


On 11/22/2023 1:43 PM, Dietmar Kasper wrote:

GM topbanders
propagation was not good. No US on CW but terrible crashes from thunderstorms 
between Singapore and Tarawa.
The complete north was a thunderstorm, just see 
https://www.accuweather.com/en/tl/national/weather-radar
Took my free time what actually was adicted to sleep to improve US beverage. It 
was extended in length
and converted into a two wire beverage also to cover backside to Indian Ocean.

Had to pay the price for extra sunshine and had to take some sleep in the 
evening, so missed the US time.
As soon as I was away the station was hijacked by the FT-lovers to play their 
computer games.
Spots show that computer cannot work US better as humans during thunderstorm 
crashes, so most contacts
were loud JAs and US stations we already worked in CW.

I feel like the last person on earth fighting for the CW mode on topband. 
However FT lovers
were not seen when it came to put out the beverages, look for the noise source 
near the property or
to reconstruct the beverages far away during hours and hours of hard labour.
Originally it was planned to have another 160m antenna on second location but 
nobody wanted to do the
work - is is so much easier to take over a good working CW station when the 
lonely after many nights
tired person is away for a while.

Band was closed most parts of the night but a few loud JAs (mostly dupes) 
called in. At sunrise
we had a short opening starting with G4AMT followed by I3, ON, EI, DL, HB9 and 
then the sun was
up and the band was dead again. These are the moments I like so much to do the 
real top band DX
what you can hear and feel - and good to know lot of the person behind the call.
Artificial intelligence just clicks the contact and goes ahead - obviously our 
future :-)

OK - lets bring this DXpedition to an end and this will be my last entry in 
this group or in
any other group mostly addicted to the FT modes.
73 Dietmar DL3DXX
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Re: Topband: CQWW160: Night 2

[Michael Tope]

There was a decent opening from here in Southern California to Europe on 
Saturday night around 0500 UTC that lasted approximately two and a half 
hours. Over the course of the opening, I heard stations from 9A, OM, YU, 
S5, DL, PA, G, GW, E7, and GJ. I was able make QSOs with DL and GJ (and 
I had a maybe with E7). I was hoping that similar circumstances would 
materialize for the Sunday morning opening to Asia. When I heard K0DI in 
Florida work a JA station, I became even more convinced that we were in 
for a JA bonanza later in the morning. Unfortunately it was a huge bust. 
It was as if someone dropped a huge D-layer cloud over Japan. Strangely 
enough, several BY stations seemed to be unaffected by the poor 
propagation, in particular, BY4SZ who had a massive signal in Southern 
California. Unfortunately, he was hearing impaired. I think W6YA might 
have gotten through to him, but I certainly didn't. I heard one DU 
station, but he also couldn't hear me.


Never take propagation from granted on Topband :-)

73, Mike W4EF..

On 1/29/2023 12:51 PM, Tree wrote:

Could have been band conditions not working very well.  Felt like a thick
cold blanket was on top of the band last night.

This morning - normally very loud stations in MT were just regular signals
- not much stronger than BY4SZ.

Only managed one JA QSO with JH4UYB this morning.  JA3YBK could not hear
me.  Band was quiet - but very attenuated.

Surprised however to work 3W1T right at sunrise and 4F2KWT before that.
Heard a few other DU's but they were not hearing me.

Tree N6TR / K7RAT

On Sun, Jan 29, 2023 at 12:37 PM Jim Brown 
wrote:


On 1/29/2023 9:25 AM, w3...@roadrunner.com wrote:

had to run the 52' vertical- 0.25 wave 160m
INV-L against a single ground rod. But it works quite well, even so.

It wasn't "working quite well" when you were buried in my noise last
night. We worked, but it wasn't easy. Thanks for the QSO.

73, Jim K9YC
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Re: Topband: Small Loop does not receive weak signal on 160m BOUVET RX SPOILER

[Michael Tope]

I had an interesting experience along these lines back in 2006 for the 
CQ WW 160 CW contest. Following the lead of K6SE and others, I got 
permission from the Bureau of Land Management to operate from the salt 
evaporation ponds on Koehn dry-lake near Mojave, California. I spent all 
day Thursday setting up the transmit antenna and when I started 
listening Thursday night my heart sank. The static crashes were 20 over 
S-9 and it was difficult to hear much of anything. I was worried that 
the weekend might be a bust. I had the parts with me for my home-brew RX 
4-square, but it wasn't installation friendly and there was way too much 
to do on Friday morning to have any hope of getting it up and installed 
in time for the start of the contest. Fortunately, as it turned out, 160 
was a completely different band the next two nights. All of the static 
crashes were gone and the band was amazing just listening on the TX 
antenna. I worked over 100 Asian stations that weekend (mostly JAs). So 
yeah, using the transmit-antenna for receive at a location with low 
ambient ground-wave noise can work, but as George aptly points out it's 
a crap-shoot.


73, Mike W4EF.

On 12/25/2022 7:36 AM, GEORGE WALLNER wrote:
In my experience, a DXpedition does not need an RX antenna on 160 for 
the first two to three days. During that time they are working the big 
guns with strong signals. The RX antenna is needed to give the weaker 
stations a chance once the big guns are out of the way.
In case of Bouvet, most of the signals will be coming from the NE or 
NW direction. Their "back" will be towards Antarctica, which is not a 
major source of noise. The F/B of an RX antenna will contribute little 
(but not zero).


The bigger problem will be that Bouvet Island is in the southern 
hemisphere, where it is summer this time of the year. Late-afternoon 
or evening thunderstorms taking place south of the Equator will 
generate a lot of noise (think of Africa, Amazon). Most of that noise 
will be coming from the same direction as the the NA and EU signals, 
in which case an RX antenna may not help (much). Their biggest 
challenge will be working the Far East (JA especially). That is where 
a good RX antenna, pointed in the right direction, could help because 
most of the noise would be coming from its side. With marginal TB 
QSO-s even a fraction of a dB in S/N can make the difference . Also, 
they wont have much darkness to work with. It will be tough. I would 
make the loop bigger to improve the S/N ratio and improve the JA-s' 
chances.

73,
George,
AA7JV/C6AGU
On Fri, 23 Dec 2022 23:03:36 -0600  wrote:

I was one of the 160m ops at "nearby" FT5XO.  I can tell you that when
the
WX was good the TX antennas worked very well for receiving. When the
WX turned bad, such as during the snow storm we worked through, the 160m
TX antennas
were very noisyjust as noisy as those anywhere on the planet.

Don't get me started about those awful 160m fishing buoy transmitters!!

73,
Charlie, N0TT

On Fri, 23 Dec 2022 19:45:28 -0700 Wes  writes:

All interesting.  But let me ask (and standby for flames) what is 
wrong with them simply listening on the TX antenna?
I know, I know, conventional wisdom says that you can't possibly 
work 160 DX without a separate RX antenna.  I'll confess that I am a 
little pistol and will never be on the TB Honor Roll, but I got on 
the band just to add another DXCC band to my collection (now nine). 
 I'm now at 144 confirmed, running just 500W and a 55' inverted-L on 
both TX and RX. Generally speaking I hear better that I get out.
Looking at my chances of working 3Y the optimum time is their 
sunrise (~3:30Z) when I am in complete darkness and straight across 
the terminator. They will have the sunlit ocean to their rear and 
the S. American landmass toward me.  Maybe someone can enlighten me, 
but I fail to see how a directional antenna will improve the SNR of 
my signal at their end.

Wes  N7WS

On 12/23/2022 6:46 PM, JC wrote:> Hi topband lovers>>   >> Some 
friends contact me with deep concerns about the next Bouvet DX 
expedition receiver antenna called SALAD>>   >> 

<
http://www.lz1aq.signacor.com/docs/active-wideband-directional-antenna.p
hp>
Salad antenna>>   >> I understand the concerns, Bouvet on 160m is a 
lifetime opportunity for most top-banders!>>   >> When Doug NX4D, me 
N4IS and Dr Dallas started to try to understand the limitation of 
the new Waller Flag, the first big question was;>>   >> How small a 
loop antenna can be to receive weak signal on 160, or MW?>>   >> Dr. 
Dallas Lankford III (SK), measured the internal noise of a small 
loop. 15x15 FT on his quiet QTH, and wrote a paper with the 
derivation necessary to calculate the thermal noise of a small loop. 
The study most important point was:>> >> The sensitivity of small 
loop antennas can be limited by internally generated thermal noise 
which is a characteristic of the loop itself. Even amplifying the 
loop output with the 

Re: Topband: J28MD, conditions

[Michael Tope]

I spent all morning calling T88WA on 160CW FT8. They responded to my 
call twice in a row in the wee hours of the morning when their signal 
strength was modest (~R -15), but I never saw the "RR73", message so I 
kept trying to work them for hours until the sun came up. In the lead up 
to sunrise they became very loud for quite a while (something like R 
+1), so I was kind of dumbfounded that they never responded again while 
stations with whom I am normally competitive were getting through. I was 
beginning to think that something was wrong with my antenna, that 
perhaps copper thieves had made off with all my ground radials. I walked 
outside after sunrise to make sure they were still there. This 
afternoon, I checked the coax loss and it was reasonable (~0.5dB). What 
the heck?


After all the aforementioned head scratching, I discovered this 
afternoon much to my surprise that I am in the log. They were splitting 
streams, so all I can figure is that they sent the RR73 in a split 
stream and it was too weak for me to decode; and then they just ignored 
me afterwards because they considered me a dupe. I would have been quite 
happy to have avoided all those extra hours of calling and gone to bed 
instead had I know I was in the log.  My experience with FT8 is pretty 
limited. Is this a common problem?


73, Mike W4EF

On 11/7/2022 12:18 PM, Wes wrote:

IMHO, that's a bug.

On 11/6/2022 7:53 PM, Chortek, Robert L. wrote:

That’s standard F/H.

  If they put your call in the queue, and your transmission times out 
(or you quit calling), the software activates your transmitter.  In 
effect you had already worked him (you just didn’t know it yet) - not 
really but sort of.


73,

Bob/AA6VB
Robert L. Chortek


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Re: Topband: J28MD, conditions

[Michael Tope]

Thanks for pointing this out, Wes. I went back a re-read the primer on 
using "hound" mode in a less sleep-deprived state (still sleep deprived, 
but not nearly as much). Sure enough it describes how the hound's 
frequency gets moved to the frequency where the "fox"  responded. It 
seems that the computer tried to do exactly what is was supposed to do. 
It's a miracle that P29RO logged me given all my attempts to sabotage 
the intended course of events. 


73, Mike W4EF.

On 11/5/2022 4:26 PM, Wes wrote:
I'm far from an FT8 expert* but on F/H mode the Fox does move the 
selected hound to his frequency.  If contact is not completed on the 
first sequence he will move the hound to another frequency, rinse and 
repeat once more and you need to start over.


To their credit, IMHO, P29RO is actually also working traditional 
RTTY.  I now have them on 5 bands on RTTY.


* A couple of my clubs have impromptu "competitions" on certain 
DXpeditions where the scoring is the number of slots (band/modes).  So 
if you want to compete, you have to use FT8/FT4.  I kick and scream 
and work them, but to date I refuse to claim DXCC credit for the Qs.  
This has created a personal dilemma, because my DXCC number 339 is Mt 
Athos on FT8.  I haven't claimed it and probably won't unless I work 
#340, Glorioso, which will probably never happen in this lifetime.


Wes  N7WS

On 11/5/2022 2:50 PM, Michael Tope wrote:
I am glad to hear T88WA is not at the hotel club station. The club 
station has a low dipole on 160 which in the past has made a poor 
showing.


I managed to get a response from P29RO on 160 meter FT8 on Friday 
morning, but didn't think it was a complete QSO. I am new to "hound" 
mode and WSJT-X kept changing my transmit frequency. I think I was 
calling at 1086 Hz, and when I got the response from P29RO, the 
program moved my TX frequency to match the P29s QRG (504 Hz) and 
responded there. Not sure what was going on. In any case, I was a bit 
stunned to see that I showed up in the P29 log. I suppose our 
exchange meets the bare minimum for a QSO - their computer decoded my 
call and signal report and my computer decoded theirs. Definitely not 
as satisfying as a clean CW QSO, but I am pretty certain they were 
too weak for that. Much of the time I wasn't decoding them and 
couldn't see them on the waterfall display.


73, Mike W4EF


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Re: Topband: J28MD, conditions

[Michael Tope]

I am glad to hear T88WA is not at the hotel club station. The club 
station has a low dipole on 160 which in the past has made a poor showing.


I managed to get a response from P29RO on 160 meter FT8 on Friday 
morning, but didn't think it was a complete QSO. I am new to "hound" 
mode and WSJT-X kept changing my transmit frequency. I think I was 
calling at 1086 Hz, and when I got the response from P29RO, the program 
moved my TX frequency to match the P29s QRG (504 Hz) and responded 
there. Not sure what was going on. In any case, I was a bit stunned to 
see that I showed up in the P29 log. I suppose our exchange meets the 
bare minimum for a QSO - their computer decoded my call and signal 
report and my computer decoded theirs. Definitely not as satisfying as a 
clean CW QSO, but I am pretty certain they were too weak for that. Much 
of the time I wasn't decoding them and couldn't see them on the 
waterfall display.


73, Mike W4EF


On 11/5/2022 10:30 AM, Wes wrote:
Not making much noise here, but sure hearing a lot.  I did work PJ4K 
on 10/30 on SSB no less.  I'm almost sorry to say I dropped down to 
FT8 and worked 25 JA stations in a run.  On 11/2 I worked DU7ET and 
that's it from my modest station in the Sonoran Desert.  The Pacific 
expeditions, the mainstays from the west side of the country, are 
non-starters. P29RO has decided no CW on TB because of hearing 
problems (I know the feeling).   A35GC hasn't shown up and T88WA is 
supposedly still building an antenna.  Unfortunately, the guys down 
under seem to quit before I'm out of bed, even at 4:30 AM like this 
morning.  I think that after Bouvet, whether I work them or not, I'll 
convert the inverted-L to something more useful.


Wes  N7WS

On 11/5/2022 9:00 AM, David Raymond wrote:

Greetings Topbanders. . .

I've spent a considerable amount of time on watch this past week for 
J28MD on Topband (CW).  While they've spent a fair amount of time on 
TB I haven't yet had success yet in spite of my ongoing efforts.   I 
believe it was this past Tuesday night when Joel, W5ZN, said they 
appeared briefly out of the noise (about 10 minutes or so and did 
have success with his BSEF-8 and Hi-Z 8 arrays in diversity)  then 
disappeared the rest of the evening. Wednesday night's opening to NA 
was much longer starting on the East coast and slowly sweeping 
westward with quite a few NA making it in the log (EC + 5's, 8's, & 
9s', VE). Unfortunately the prop just never quite made it this far 
west. They barely peaked out of the noise here in Iowa Wednesday 
evening (NA time) just enough to get me excited and dump my call a 
few times hoping for even a marginal QSO. . . but no cigar. It's a 
little frustrating to see that they always QRT about 30 minutes or so 
prior to their SR but they get credit for being on faithfully on CW 
and FT8 as well.  I know they're getting close to wrapping up but 
hopefully they'll be on (CW) again this evening.


It's been good to have some DX operations QRV and bring some much 
needed life to TB (which sure hasn't had much). . .TY0, 5V, and now 
J28, A3, and T88.  The prop has been very poor.  CQing here in the 
evening brings no DX responses and only a handful of EU EBN hits so 
far this season.  Thankfully mornings have activity from our very 
stalwart VK friends (VK3HJ, VK2WF, VK6GX, VK6IR, VK6LW, others) but 
only a handful of JA QSOs so far this season (8 to be exact).  JA1LZR 
gets kudos for being QRV almost every morning (NA time),  but without 
much prop, I think only limited success.    I have yet to hit the 
VK4CT RBN CQing here in the mornings.  I don't think this is totally 
attributable to the increased SFI. . . prop from here was only 
marginally better two seasons ago when the SFI was very low.


All that said, I encourage everyone to get on and make some noise.

73. . . Dave, W0FLS (in Iowa)

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Re: Topband: Relay bounce

[Michael Tope]

Steve,

Does the switch produce an S9 spike on any transition of the switch 
(i.e. from position N to position N+/-1) or only on a certain subset of 
switch transitions? That might provide a clue as to whether there is a 
problem with one of the relays or the power supply that energizes them. 
I am wondering if it could be a bad filter capacitor in the relay 
control circuits or a bad DC blocking cap over on the switch end.


I am not convinced that dirty relay contacts could cause the noise 
spike, but it is probably  agree to clean the relay contacts anyway just 
in case. W8JI recommended soaking a piece a paper in a liquid 
hydrocarbon (I think he used Xylene) and then passing that paper between 
the contacts of the relays in order to transfer any foreign material to 
the paper without causing undue abrasion to the relay contacts. I've 
done this and it has fixed the problem of an RCS-4 going deaf on receive 
despite still working for transmit. For receive only applications you 
might have to do it more often.


73, Mike W4EF...

On 2/22/2022 10:04 AM, Steve London wrote:

I am using an Ameritron RCS-4 antenna switch to select between beverage
antennas. Recently, it has developed a bad case of relay bounce causing an
S9 spike every time I switch between antennas. Any suggestions on how to
improve this ? Since it's only used for RX antenna selection, I'm amenable
to replacing the relays with something else, although I have had issues
before with other relays due to no current going through the contacts.

Thanks and 73,
Steve, N2IC
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Re: Topband: Series LC to notch AM broadcast ?

[Michael Tope]

Hi Jim,

When I lived in Melbourne Florida, I had an 920 KHz AM station with a 
four tower array a short distance from my house (I forget the exact 
distance, it was probably on order of 1/2 mile). The daytime pattern 
beamed toward my house with a TPO of 5KW. At the time I was using a 
Ten-Tec Paragon. During the day I would get all sorts of cross-mod when 
listening on my 80/40 meter fan dipole.


After some trial and error, I discovered a little external attenuation 
would cure the problem, but the Paragon's internal attenuator wouldn't 
help. It turned out the signal pickup from AM 920 was so strong it was 
overwhelming the bias applied to the PIN diodes used to switch coverage 
segments in the Paragon's front-end filters The Paragon used relays to 
switch in low-pass filters which were in both the receive and transmit 
paths, but the high-pass filters were only used for receive and were 
switched with these PIN diodes. I built a small low-Q notch for 920 KHz 
on a perfboard and installed it in the portion of the Paragon's receive 
path between the T/R relay and the PIN diode switched filters.


The notch provided enough attenuation to completely eliminate the 
cross-modulation. There was a marked decrease in sensitivity around 920 
KHz, but it didn't render the Paragon receiver totally dead in that 
portion of the BC band, so I never bothered to make the notch relay 
switchable.  I just left it in all the time.


Later on I got an ANC-4 noise canceller and discovered a different 
problem. A simple high-pass eliminated overload of the ANC-4 receive 
path from 920 KHz AM, but it turned out that there was another local AM 
transmitter on 1580 KHz. This one was further away, thereby not strong 
enough to cross-modulate PIN diodes, but plenty strong enough to 
overload the front-end of the ANC-4 receive path. For this I built a 
three section high-pass with two series C/shunt-L sections and one 
parallel tuned notch section set to 1580 KHz. This did the trick. This 
was also an RX only filter. I believe I ended up adding a standard ICE 
high-pass to the transmit path, but I don't recall exactly why.


This work was all done circa 1995/1996 before I moved to California. 
Recently when this topic came up on the reflector, I went hunting for 
the schematic of this filter, but was unable to find it. I did, however, 
find the filter in drawer full of RF odds and ends. It's built inside of 
an enclosure made of pieces of double-sided circuit board material 
soldered together. When I have some spare time, I need to sit down and 
sweep it on a network analyzer and create a schematic for it. Same goes 
for the notch inside the Paragon. I still have the rig, but would need 
to take it apart to document the schematic. Both schematics may exist 
somewhere, but there is no guarantee so I figure biting the bullet and 
reverse engineering the filters will be faster and much less annoying 
than trying to find written documentation that may no longer exist 


As far as what values to use, you should be able to simulate this with 
LTSpice and/or QUCS. With ideal components you can make the notch as 
deep and narrow as you want, but reality bites when you throw in the 
temperature stability of the components and their finite unloaded Q (in 
particular the inductor). There are also voltage extremes that come into 
play with very high loaded Q series notches that are placed in the 
transmit path (and current extremes for parallel resonators with high 
loaded Q). I suspect if you fiddle around with an inductor unloaded Q of 
100 in simulation, you'll get a good feel for what is practical. To nail 
multiple interfering stations, you might try looking at an elliptic 
filter design (i.e. Cauer) which has an "equal ripple" stopband 
(https://en.wikipedia.org/wiki/Elliptic_filter). The elliptic filter 
includes transmission zeroes in the form of LC resonators which put deep 
notches at various points in the filter stopband.


Here is an example of a QUCS elliptic filter simulation:
https://rf-tools.com/lc-filter/description.html#qucs (click on "Example 
1: S-Parameters").


73, Mike W4EF

On 2/20/2022 9:41 AM, jim.thom jim.t...@telus.net wrote:

Has anybody tried using a simple series L-C to notch out ONE offending AM
broadcast station ?  I'm talking about wiring from hot side of coax...to
chassis / groundlike via a T connector etc.

On paper, it should work. Did some minor research, and one comment was that
by using higher values of L would result in  higher Q..and a deeper notch.
Another comment stated to use some initial values, like what spits out on a
L-C  online calculator for practical values. then  multiply one value
by the other...then take the square root of the result.   Then you ended up
with 2 x numerically equal values of L + C. and supposedly the greatest
notch depth.

On software, I tried several values..from one extreme to the other, and
they all resonate on the same freq.   Also tried in 

Re: Topband: FW: The WD8DSB mini-flag antenna (LONG!)

[Michael Tope]

Hi Jim,

From the P3 manual:/
/

   /"The dsPIC further processes the signal for presentation on the
   480x272-pixel color TFT LCD display. The "circuitry" shown inside
   the processor box in the block diagram is actually implemented as
   software routines. The FFT is the fast Fourier transform, which is a
   software version of a hardware spectrum analyzer. It reads the
   incoming signal and calculates the frequency spectrum. Further
   software routines calculate the power of the spectrum, take the
   logarithm, and then scale and offset the result so that it reads
   correctly in dBm on the display."

   /

The raw samples will be in volts, but what gets displayed depends on the 
processing. The FFT spits out a complex number for each bin. If you take 
the magnitude of that complex number and square it, you get a number 
that is proportional to the power in that frequency bin averaged over 
the length of time that the FFT samples (e.g. 4096 samples @ 60 
Megasamples/sec would be a time interval of 4096/60e6 = 68us).


The random Johnson noise voltage you get from a resistor has a two-sided 
Gaussian distribution with zero mean and standard deviation sigma, so 
the random noise voltage does average to 0 volts. The noise power on the 
other hand has a one-sided Gaussian distribution with a variance of 
sigma^2. If you average after conversion to power (this is what is 
typically done in a spectrum analyzer), the random noise won't average 
to 0.0 watts, instead it will converge toward the average noise power 
(i.e. number proportional to sigma^2). This is why the thermal noise 
displayed on a spectrum analyzer doesn't tend toward minus infinity dBm 
when you average it, instead it tends toward sigma^2 as you apply more 
averaging.


When you calculate KTB and convert that to dBm (e.g. -174 dBm for room 
temperature in a 1 Hz bandwidth), you are getting the sigma^2 value. But 
the Gaussian distribution has tails that extend beyond 1 sigma,  that is 
why the displayed noise has jagged peaks before it is averaged. Some of 
the noise power samples taken in the time interval of the FFT are going 
to be less than sigma^2 and some are going to be significantly greater 
than sigma^2, but if you average enough of them (from any given 
frequency bin), you get a number that converges toward sigma^2.


73, Mike W4EF

On 2/25/2021 7:39 PM, Jim Brown wrote:

On 2/25/2021 5:16 PM, John Kaufmann via Topband wrote:
The P3 averages power, not amplitude, so using longer averaging times 
just

smooths the display and doesn't reduce random noise.


It has nothing to do with power. Last I looked, the P3 is reading and 
displaying the instantaneous voltage in the IF, and can be calibrated 
to voltage at the input.


I've been doing swept measurements of complex quantities for nearly 40 
years, first at audio frequencies and now at RF. Averaging DOES cause 
random contents of a bin to approach zero (or the noise floor), making 
correlated signals stand out. This has long been well understood.


I the principle to measure the dynamic response of broadcast signal 
processing in a peer-reviewed paper to the Audio Engineering Society 
in 1986.  The test signal was a swept sine embedded deep in musical 
program material to the point that it was barely audible to a trained 
listener, and detected by a synchronized swept narrowband detector. 
Because the swept excitation and swept detector are synchronized, the 
measurement produces the complex response of the system, and program 
material, being non-coherent, averages out.


http://k9yc.com/AESPaper-TDS.pdf

73, Jim K9YC
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Re: Topband: W6 to EU openings last night

[Michael Tope]

I tried calling CQ on CW at around midnight local (0800z) this morning 
and worked JE1CTM, G3PQA, G3OQT, and G3OLB in succession all with good 
signals into Southern California. This came after an absolute bounty of 
European QSOs on FT8, including a number of eastern European QSOs. 
HB9BIN was showing an FT8 "R" reading peaking well over +10 (+14 I 
think) and he stayed consistently over +5 for quite some time. He was so 
strong I kept wondering if it might be someone in the states pirating 
his call. There was, however, a lull earlier in the evening where the 
band appeared to shut down completely to Europe (no FT8 decodes 
whatsoever). I was really surprised that things opened back up the way 
they did.


73, Mike W4EF...

On 1/5/2021 6:47 AM, Richard (Rick) Karlquist wrote:


On 1/4/2021 12:43 PM, Roger Kennedy wrote:


I didn't come on last night . . . but I've been working across to Texas,
Colorado and Arizona over the past week or so.

What sort of time were your QSOs Rick?  (will look out for you tonight)

73 Roger G3YRO



The openings were around 0400 to 0500 UTC.
(Tuesday morning UTC, Monday night in CA)
Last night I was listening a little earlier
and heard W0FLS working a DH1 station, but
nothing from the EU end was audible, not
even waterfall tracks.

73
Rick N6RK
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Re: Topband: 160m Conditions for the CQ WW SSB

[Michael Tope]

I heard JH4UYB on Sunday morning calling CQ on SSB with a good signal, 
but he couldn't copy me. I believe he was operating above the FT8 
segment, but I don't recall his exact frequency.


73, Mike W4EF.

On 10/26/2020 6:45 AM, mw_comerc...@wp.pl wrote:

Hi,

did anyone work any JA on 160m SSB this weekend?
There were some changes in the bandplan, aren't they already allowed 
to work up to 1875 any mode?


73s
Mac SP2XF

-Oryginalna wiadomość- From: Roger Kennedy
Sent: Monday, October 26, 2020 11:33 AM
To: topband@contesting.com
Subject: Topband: 160m Conditions for the CQ WW SSB


Well I was hoping to have some SSB DX contacts on 160m, but conditions 
were

really poor from this side over the weekend . . .

Only managed to hear & work a couple of NA stations.

Even most Europeans weren't very strong at all !

Roger G3YRO

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Re: Topband: Ground Conductivity

[Michael Tope]

Dan,

Reading that QRZ.com thread you linked to and reflecting on K4SAV's 
measurements and how much they appeared to vary over a fairly short 
period of time, got me wondering about what could be responsible. I am 
fairly certain that at least part of the radial system for my 160 meter 
vertical is over the drain field of the septic system for my cabin. Who 
knows, maybe a properly timed toilet flush could make the difference 
between working a new one and coming up empty :-)


Okay, the toilet aided pileup busting is a stretch, but seriously, I am 
not sure if I can think of any better explanations than septic discharge 
for why ground characteristics could change that quickly. I do know in 
some cases there can be water table very close to the surface, but I 
don't know how much that typically varies over the short term. My only 
other thought is that maybe in K4SAV's case the lay of the grass under 
the wire is changing slightly over time and the impedance is 
super-sensitive to the gap between the antenna and the ground (although 
I think K4SAV said that his grass was all dead).


73, Mike W4EF..

On 3/23/2020 10:18 PM, Dan Maguire via Topband wrote:

Grant wrote:

If you really want to know the parameters, see antennasbyn6lf.com as Rudy 
describes techniques for ground RF properties measuring.

Turns out that very subject was being kicked around on a recent qrz.com thread:

https://forums.qrz.com/index.php?threads/indirect-measurement-of-ground-constants-with-a-dipole.696955/

Dan, AC6LA
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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Roger,

When you checked for increased noise on 10 and 15 meters, did you have 
your radio set for maximum sensitivity and were the main and AUX input 
ports of the MFJ-1025 terminated with 50 ohms (or at least not connected 
to any outside antenna)?


73, Mike W4EF.

On 3/17/2020 11:18 AM, Roger Kennedy wrote:

Having just read some of these posts, I just did a few tests on my MFJ-1025.
(bought mine second-hand very cheap - a lot of people buy these thinking
they will get rid of any noise!)

I modified it to become a 1026 . . . you definitely need the extra pre-amp
for the "Noise Antenna", especially on 160m - fortunately they use the same
PCB for both versions, so you can easily add their extra preamp circuit
design on the PCB.

I normally only use mine on 160m . . . but just did a test on 15m & 10m . .
. it adds no noticeable noise whatsoever !

So I think the OP's must be faulty . . perhaps powering it by a noisy PSU?

Roger G3YRO



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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Hi Mike,

I was trying to address the particulars of N2IC's situation which 
involved the higher HF bands (although at this point in the sunspot 
cycle, perhaps I should have included 20 meters).


Reading the manual I have for the MFJ-1026 says "The MFJ-1026 is 
optimized over the range of 1.8 to 30 MHz". Does the MFJ-1025 only go to 
20MHz?


73, Mike W4EF


On 3/17/2020 10:31 AM, Mike Waters wrote:

Mike, is there any reason why you tested it above 20 MHz? That's outside
the 1026's specified frequency range.

73, Mike
W0BTU

On Tue, Mar 17, 2020, 9:07 AM Michael Tope  wrote:


I just happen to have a spare MFJ-1026 at home. I did a real quick test
using my FT1000MP MK-V while powering the MFJ-1026 from an Astron
supply. Similar to your results, Steve, I got about a 12 to 14 dB
increase in the noise floor on 10 meters when the MFJ unit was turned on
and connected to the MK-V's main antenna input versus when the MFJ unit
was powered off. This suggests you would have to resort to having
low-noise pre-amps ahead of each of the MFJ-102x two signal paths and
the right amount of attenuation after the MFJ-102x's combined output to
work in your particular very low noise situation.

Since the main antenna path is normally bypassed for transmit, to put a
pre-amp ahead of the main antenna path you would have to either move
that MFJ-102x out of the transmit path by putting it in a receive-path
breakout-loop that is common on many modern transceivers (e.g. between
RX_OUT and RX_IN jacks), or you would have to have add a dedicated T/R
bypass scheme for the external main path pre-amp.

FWIW, I also made some gain measurement on my MFJ-1026 (both main and
sense path gain controls fully clockwise):

Main Antenna Path Gain:
10 Meters: 4dB
15 Meters: 3dB

Sense Antenna Path Gain (sense-path pre-amp on and internal jumpers set
for maximum gain):
10 Meters: 0.5dB
15 Meters: 1.6dB

Difference between having Sense Path Pre-Amp On vs Off:
10 Meters: 8dB
15 Meters: 9dB

I used an Elecraft XG3 as the signal source and an HP141T to measure
amplitude.

73, Mike W4EF...



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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

You were spot on, Dave. Thanks for the suggestion. I rechecked the 
numbers this morning and the AUX (i.e. sense antenna path) gain varies 
about 2dB as a function of where the phase control is set. It appears I 
had the phase control sitting in the worst-case minimum gain position 
(apparently quite by accident) which seems to occur around "8" or "9". 
The maximum gain occurs with the control fully clockwise at "10", so 
there is a lot of variation between "7" and "10".  Between a phase 
control setting of "0" and "7" the change in the sense path gain is much 
smaller. When you flip the phase polarity, there is a small amount of 
gain change. The maximum gain numbers are pretty close to the main 
antenna path numbers.


10 Meters: 2.8dB (0.5dB min)
15 Meters: 4.6dB (2.6dB min) [note: the 1.6dB number previously reported 
may be an error]


Please take the decimal point with a grain of salt. These are not lab 
grade measurements [think quick and dirty order-of-magnitude measurement 
done with a fair amount of haste]. The cables and adapters I used should 
probably be thrown away and replaced with better quality parts and it's 
possible Nixon was still president the last time the 141T was calibrated 
to NIST standards :-)


73, Mike W4EF.

On 3/17/2020 9:56 AM, Dave Cuthbert wrote:

Mike, thank and these are great data points you've provided.

Questions:
Was the MFJ-1026 PHASE control set near zero? That could account for 
the low AUX gain.


*Mike's data*
FT1000MP MK-V

Main Antenna Path Gain:
10 Meters: 4dB
15 Meters: 3dB

Sense Antenna Path Gain (sense-path pre-amp on and internal jumpers set
for maximum gain):
10 Meters: 0.5dB
15 Meters: 1.6dB

12 to 14 dB increase in the noise floor on 10 meters when the MFJ unit 
was turned on


*MFJ-1026 MAIN measured noise and calculations*
Sherwood Engineering measured the FT-1000 MP MKV Field at -133 dBm in 
500 Hz BW. This is -160 dBm in 1 Hz, or 2.2 nV/Hz^0.5.


The 12 to 14 dB increase in the noise floor with the MFJ-1026 
activated tells us its output noise power is ~13 dB above -133 dBm, or 
-120 dBm in 500 Hz BW. This is -147 dBm, or *10 nV/H^0.5.* Given the 
measured AUX path gain of 0.5 dB this tells us the MFJ-1026 AUX 
input-referred noise is *~9 nV/Hz* on 10 meters. But wait, there's more.


In my March 16 email I said "The MFJ-1025 [calculated] output noise 
is*9 nV/Hz^0.5."* But, given the MFJ-1026 measured AUX gain of 0.5 dB 
(10 meters) when I estimated 14 dB AUX gain (20 meters) is a huge 
discrepancy. This points to the phase shifter circuit attenuating the 
signal. Might the PHASE control knob be set to 0? This attenuates the 
AUX path.


*Notes*
The MFJ-1025 and MJF-1026 use the same circuit with the 1026 adding a 
whip antenna amplifier.


*References*
https://www.mfjenterprises.com/support.php?productid=MFJ-1026

http://www.sherweng.com/table.html

http://www.sherweng.com/documents/TermsExplainedSherwoodTableofReceiverPerformance-RevF.pdf 



    Dave KH6AQ

On Tue, Mar 17, 2020 at 4:07 AM Michael Tope <mailto:w...@dellroy.com>> wrote:


I just happen to have a spare MFJ-1026 at home. I did a real quick
test
using my FT1000MP MK-V while powering the MFJ-1026 from an Astron
supply. Similar to your results, Steve, I got about a 12 to 14 dB
increase in the noise floor on 10 meters when the MFJ unit was
turned on
and connected to the MK-V's main antenna input versus when the MFJ
unit
was powered off. This suggests you would have to resort to having
low-noise pre-amps ahead of each of the MFJ-102x two signal paths and
the right amount of attenuation after the MFJ-102x's combined
output to
work in your particular very low noise situation.

Since the main antenna path is normally bypassed for transmit, to
put a
pre-amp ahead of the main antenna path you would have to either move
that MFJ-102x out of the transmit path by putting it in a
receive-path
breakout-loop that is common on many modern transceivers (e.g.
between
RX_OUT and RX_IN jacks), or you would have to have add a dedicated
T/R
bypass scheme for the external main path pre-amp.

FWIW, I also made some gain measurement on my MFJ-1026 (both main and
sense path gain controls fully clockwise):

Main Antenna Path Gain:
10 Meters: 4dB
15 Meters: 3dB

Sense Antenna Path Gain (sense-path pre-amp on and internal
jumpers set
for maximum gain):
10 Meters: 0.5dB
15 Meters: 1.6dB

Difference between having Sense Path Pre-Amp On vs Off:
10 Meters: 8dB
15 Meters: 9dB

I used an Elecraft XG3 as the signal source and an HP141T to measure
amplitude.

73, Mike W4EF...




On 3/16/2020 9:47 AM, Steve London wrote:
> This has been a very interesting thread - Thanks for all the input.
>
> Perhaps I have set my expe

Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

I just happen to have a spare MFJ-1026 at home. I did a real quick test 
using my FT1000MP MK-V while powering the MFJ-1026 from an Astron 
supply. Similar to your results, Steve, I got about a 12 to 14 dB 
increase in the noise floor on 10 meters when the MFJ unit was turned on 
and connected to the MK-V's main antenna input versus when the MFJ unit 
was powered off. This suggests you would have to resort to having 
low-noise pre-amps ahead of each of the MFJ-102x two signal paths and 
the right amount of attenuation after the MFJ-102x's combined output to 
work in your particular very low noise situation.


Since the main antenna path is normally bypassed for transmit, to put a 
pre-amp ahead of the main antenna path you would have to either move 
that MFJ-102x out of the transmit path by putting it in a receive-path 
breakout-loop that is common on many modern transceivers (e.g. between 
RX_OUT and RX_IN jacks), or you would have to have add a dedicated T/R 
bypass scheme for the external main path pre-amp.


FWIW, I also made some gain measurement on my MFJ-1026 (both main and 
sense path gain controls fully clockwise):


Main Antenna Path Gain:
10 Meters: 4dB
15 Meters: 3dB

Sense Antenna Path Gain (sense-path pre-amp on and internal jumpers set 
for maximum gain):

10 Meters: 0.5dB
15 Meters: 1.6dB

Difference between having Sense Path Pre-Amp On vs Off:
10 Meters: 8dB
15 Meters: 9dB

I used an Elecraft XG3 as the signal source and an HP141T to measure 
amplitude.


73, Mike W4EF...




On 3/16/2020 9:47 AM, Steve London wrote:

This has been a very interesting thread - Thanks for all the input.

Perhaps I have set my expectations too high.

A typical application is on 15 meters, late in the opening, working 
JA's from here in SW New Mexico. Absent any local QRN, the band is 
very quiet. Any local noise covers the bottom layer of 5 watt JA's 
calling me.


I did some more testing with the MFJ-1025. With no antennas connected, 
the box raises the noise floor about 10 dB, irrespective of the Aux 
Antenna Gain or the Main Antenna Gain. I haven't yet tried powering 
from a battery, to make sure the power supply isn't the source. 
Assuming the J310's are quiet, that leaves the 2N5109 emitter 
follower, or the back-to-back protection diodes. Might also try 
disconnecting the RF sense circuit.


73,
Steve, N2IC
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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Dave is that -112 dBm you calculated the output referred noise? If so, 
what is the gain behind it?


Thanks,

73, Mike W4EF...

On 3/14/2020 2:13 PM, Dave Cuthbert wrote:

Steve, I ran a SPICE model of the MFJ-1095 front end. What gain there is
resides there. The next three stages have unity gain. The input noise is:

1.8 MHz, 50 nV/Hz^0.5

7.0 MHz, 26 nV/Hz^0.5

14 MHz, 19 nV/Hz^0.5

28 MHz, 13 nV/Hz^0.5

Depending on the input stage gain (I'm modeling 1 to 2 depending on the
transformer) the three following stages can up the noise by 4-5 dB.

At 7 MHz the 26 nV/Hz^0.5 is 580 nV in a 500 Hz bandwidth, or -112 dBm.
This is 2.5 S-units. *What receiver are you using, what band and what is
the bandwidth? *

  Dave KH6AQ

On Sat, Mar 14, 2020 at 6:40 AM  wrote:


This discussion of Hi Z amplifiers has been quite interesting. Excellent
information from W1FV and K7TJR.

I have an RX amp question, related but slightly off-topic.

I have an MFJ-1025/1026 noise canceler. I like to use it on the higher HF
bands
to cancel power line QRN. The noise is typically S3-S4, but I want it down
to S0
to hear the bottom layer of stations. My sense antenna works fine, and the
QRN
is canceled. However, the MFJ-1025 amplifier noise is quite significant,
often
negating the QRN cancellation. The MFJ amplifiers are J310's. Any
recommendations for something quieter ?

73,
Steve, N2IC

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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Hi Mike,

Yeah, when the off-air noise floor is a lot higher than the thermal 
noise floor from the JFET pre-amps, the imbalance I was alluding to 
wouldn't typically impact the overall noise floor since that is still 
limited by off-air noise. In Steve's particular case, aside from one 
S3-to-S4 source of QRN, it sounds like has an extremely quiet QTH. Under 
those circumstances (especially since we are talking about the higher HF 
bands), the thermal noise from the receiver can start to dominate over 
the off-air noise. That is when getting the off-air QRN levels balanced 
between the two channels (as measured going into the MFJ unit) can matter.


FWIW, I've had the same experience as you nulling out local QRN. In my 
case it is noise picked-up on my 160 meter transmit antenna that I null 
with the MFJ-1026 using a 20ft top-loaded vertical as a sense antenna 
(it's what's left of a 160M RX 4 square that got shredded by the wind 
after some varmints chewed through the guy ropes). I should be so lucky 
as to have a QTH so quiet that the hiss from those JFET preamps is the 
dominate source of noise (that's quiet!).


73, Mike W4EF...

On 3/14/2020 11:57 AM, Mike Waters wrote:

Steve,
I have an MFJ-1025, and I have never experienced your issues. I was going
to ask some of these questions myself.

I have had very good results indeed with mine for eliminating a single
source of RFI. Something at your end is not right.

Mike,
There have been cases where my 580' Beverage antennas have made a superb
sense antenna. I usually use the W7IUV preamp with the output somewhat
attenuated. Mostly, with the signal antenna being my 75m dipole (with
severe RFI) and a amplified Beverage being the sense antenna.

Every QTH and noise is different, of course. What works for someone else
might not work for you.

73, Mike
W0BTU

On Sat, Mar 14, 2020, 12:46 PM Michael Tope  wrote:


2) Is your sense antenna intrinsically inefficient like a beverage or
K9AY loop or is it something efficient like a tribander up reasonably high?
3) Is your sense antenna intrinsically efficient when you include the
feed line loss (I assume the feedline loss on your main TX antenna is
very low)?

73, Mike W4EF

On 3/14/2020 9:40 AM, n2ica...@gmail.com wrote:

I have an MFJ-1025/1026 noise canceler. I like to use it on the higher
HF bands to cancel power line QRN. The noise is typically S3-S4, but I
want it down to S0 to hear the bottom layer of stations. My sense
antenna works fine, and the QRN is canceled. However, the MFJ-1025
amplifier noise is quite significant, often negating the QRN
cancellation. The MFJ amplifiers are J310's. Any recommendations for
something quieter ?

73,
Steve, N2IC



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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Another pitfall that you have to be careful to avoid with the MFJ-1026 
is making sure the level of the QRN you are trying null that is coming 
out of the sense antenna isn't much lower in amplitude than what is 
coming out of the main TX antenna (I am talking about levels measured 
directly from each antenna without the MFJ1026 in the line). For 
example, if you are getting -100dBm of QRM from the main antenna and 
only -110dBm from the sense antenna, then you could have a problem. If 
it is the case that the QRN level from the sense antenna is lower, then 
you have to use extra gain from the preamp in the sense antenna path or 
you have to attenuate on the main antenna path to get the two QRN 
voltages matched so they'll cancel effectively. Either way, you'll 
degrade the thermal noise performance. In the former case the sense 
channel will sum-in excess thermal noise, and in the latter case the 
attenuation added in front of the J310 in the main channel will degrade 
its effective noise figure.


73, Mike W4EF.

On 3/14/2020 10:46 AM, Michael Tope wrote:

Steve,

Couple of questions to rule out gain distribution issues:

1) On the sense antenna input do you have the pre-amp turned on or off?
2) Is your sense antenna intrinsically inefficient like a beverage or 
K9AY loop or is it something efficient like a tribander up reasonably 
high?
3) Is your sense antenna intrinsically efficient when you include the 
feed line loss (I assume the feedline loss on your main TX antenna is 
very low)?


73, Mike W4EF

On 3/14/2020 9:40 AM, n2ica...@gmail.com wrote:
This discussion of Hi Z amplifiers has been quite interesting. 
Excellent information from W1FV and K7TJR.


I have an RX amp question, related but slightly off-topic.

I have an MFJ-1025/1026 noise canceler. I like to use it on the 
higher HF bands to cancel power line QRN. The noise is typically 
S3-S4, but I want it down to S0 to hear the bottom layer of stations. 
My sense antenna works fine, and the QRN is canceled. However, the 
MFJ-1025 amplifier noise is quite significant, often negating the QRN 
cancellation. The MFJ amplifiers are J310's. Any recommendations for 
something quieter ?


73,
Steve, N2IC

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Re: Topband: Slightly OT - amplifier noise

[Michael Tope]

Steve,

Couple of questions to rule out gain distribution issues:

1) On the sense antenna input do you have the pre-amp turned on or off?
2) Is your sense antenna intrinsically inefficient like a beverage or 
K9AY loop or is it something efficient like a tribander up reasonably high?
3) Is your sense antenna intrinsically efficient when you include the 
feed line loss (I assume the feedline loss on your main TX antenna is 
very low)?


73, Mike W4EF

On 3/14/2020 9:40 AM, n2ica...@gmail.com wrote:
This discussion of Hi Z amplifiers has been quite interesting. 
Excellent information from W1FV and K7TJR.


I have an RX amp question, related but slightly off-topic.

I have an MFJ-1025/1026 noise canceler. I like to use it on the higher 
HF bands to cancel power line QRN. The noise is typically S3-S4, but I 
want it down to S0 to hear the bottom layer of stations. My sense 
antenna works fine, and the QRN is canceled. However, the MFJ-1025 
amplifier noise is quite significant, often negating the QRN 
cancellation. The MFJ amplifiers are J310's. Any recommendations for 
something quieter ?


73,
Steve, N2IC

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Re: Topband: Hi Z amplifiers for 160m (LONG)

[Michael Tope]

r throughput
loss imparted by the combiner circuit).

To determine the total atmospheric noise coming out of the combiner circuit,
let's assume the atmospheric noise has a completely uniform distribution in
3-dimensional space.  That is, the strength of the atmospheric noise is the
same in every direction.  This is an idealized assumption, but is often a
reasonable approximation to reality.  Under these assumptions, the total
atmospheric noise out of the combiner turns out to be just one "atmospheric
noise unit"!  In other words, it is exactly the same as the atmospheric
noise coming out of a single vertical.  This is because the total
atmospheric noise power picked up by the array is just the gain of the array
(relative to a single vertical) averaged over all of 3-dimensional space
times one "atmospheric noise unit" (the noise picked up by a single
vertical).  That average gain is exactly 0 dB, so the total atmospheric
noise doesn't change in our idealized system.  It doesn't matter what the
antenna pattern is; the average gain is always 0 dB, which is why we did not
need to be concerned with details of how signals are phased up to form a
beam pattern.  Of course, a different gain applies to actual signals that
are coming from a specific direction and are not uniformly distributed like
atmospheric noise, which is why we see a S/N improvement when the array is
aimed at a signal of interest.

So, we have demonstrated that in relative terms, the amplifier circuit noise
power in an array of N amplified antennas goes up by a factor N whereas the
atmospheric noise does not change.  That increase in the amplifier noise
contribution relative to atmospheric noise degrades the overall noise figure
of the system.  However, as long as we keep the amplifier noise contribution
small enough, the noise figure degradation can also be kept to a minimum.
That is why having more amplified elements makes it more important to design
the antenna amplifiers for low circuit noise.

73, John W1FV






-Original Message-
From: Topband
[mailto:topband-bounces+john.kaufmann=verizon@contesting.com] On Behalf
Of Michael Tope
Sent: Thursday, March 12, 2020 4:37 PM
To: topband@contesting.com
Subject: Re: Topband: Hi Z amplifiers for 160m

Hi Lee,

Yes, if you are combining coherent signals that are not in phase, then
the each of the voltage vectors is weighted by cos(phi-i) where phi-i is
the angle between the i-th voltage vector and the 1st vector. If phi=0,
then you have the case I described previously. I can see how this can
get tricky, however, with an electrically short baseline where you are
striving for cancellation in the rearward looking direction. It's like
you cancel in the rearward direction and almost cancel in the preferred
direction :-). This degrades the SNR not because the noise is adding up,
but because the signals are subtracting down.

73, Mike W4EF.


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Re: Topband: Hi Z amplifiers for 160m

[Michael Tope]

There are a lot of SMT to DIP adapter boards out there which would allow 
newer SMD op-amps to be used in older through-hole PWB layouts.


https://www.digikey.com/product-detail/en/aries-electronics/LCQT-SOIC8-8/A880AR-ND/4754588

73, Mike W4EF.


On 3/12/2020 1:15 PM, Lee STRAHAN wrote:

John,
Yes of course you are quite correct. I stand corrected.  I should not have 
used the word power. My thinking was along the line of what Mike W4EF posted.
Just did not say it right. Also, I have never disagreed with your choice of the 
8055 as I was aware of why you made that decision. Fortunately for us there are 
some op-amps now that show some really great specs. Unfortunately for us a lot 
of the older through the hole mount parts are disappearing quickly. Surface 
mount seems here to stay.
Lee  K7TJR

From: John Kaufmann 
Sent: Thursday, March 12, 2020 4:14 AM
To: k7...@msn.com; topband@contesting.com
Subject: Re: Topband: Hi Z amplifiers for 160m

Lee,

I think you are confusing voltage and power.  For incoherent sources like 
amplifier noise, the voltages of multiple incoherent sources add in a 
root-sum-squared (RSS) fashion.  The voltage of the sum of eight incoherent 
sources is square root of eight times a single noise source, assuming equal 
combining ratios.  However, because power is proportional to the square of 
voltage, then the *power* of the combined sum is the sum of the individual 
noise powers.  This is well known in the theory of random processes, which is 
the basis of communications theory.  So, what I said earlier is correct.  For a 
system with eight amplifiers, the effective total noise power in the sum is 
eight times the individual noise powers when the sources are combined with 
equal weights.  The YCCC array does not use equal weights, so the powers have 
be weighted when combining them to get the total noise power.

73, John W1FV


-Original Message-
From: Lee STRAHAN mailto:k7...@msn.com>>
To: topband@contesting.com 
mailto:topband@contesting.com>>
Sent: Wed, Mar 11, 2020 10:22 pm
Subject: Re: Topband: Hi Z amplifiers for 160m
   Hello John and all,
   Concerning the adding the noise in a typical array. If the noise was 
coherent or exactly the same signal from each element/amp the summed noise 
would indeed be 8 times. However circuit noise is always random and incoherent 
which causes the summation to be a single noise power times the square root of 
the number of elements assuming equal levels from each amp. In the case of 8 
elements 4.5 dB increase which is no small matter as well. In the case of the 
three elements the noise summation would be about 2.4 dB higher than a single 
element.
Lee  K7TJR  OR

As the designer of the YCCC high impedance feedpoint amplifier, let me address 
some issues related to the design of the YCCC amplifier as well as feedpoint 
amplifiers in general.  If you don't want to read a lot of technical 
gobbledygook, please disregard this message.

The YCCC uses an AD8055 RF amp as the gain element.  As Lee, K7TJF, points out, there are most 
certainly better op amps out there.  However, the AD8055 was the "best" part I could find 
in a DIP-8 package.  The "better" op amps are all SMT parts but given that the YCCC 
preamp was a kit, I intentionally limited the selection to DIP-8 parts that kit builders could work 
with relatively easily on a PCB.  Not everyone is able to do a competent job soldering tiny SMT 
parts.

Within the universe of available RF op amps, tradeoffs must be made in terms of 
noise, linearity, and bandwidth.  The AD8055 is not the lowest noise part but 
it has excellent linearity and plenty of bandwidth for HF use.  At my QTH there 
is an AM BCB station 3 miles away, which makes it a somewhat challenging EMI 
environment.  The decision to run the op amp in a unity gain configuration 
comes down to linear dynamic range.  It is easy to design for more gain, but it 
is also easily demonstrated that you will begin to suffer in terms of unwanted 
intermods.  With the YCCC preamp, I get absolutely zero BCB intermods or 
distortion products in the 160m band at my QTH.

In general I do not like to use an outboard preamplifier between the output of 
the phased array combiner circuit and my receiver because it degrades the 
linear dynamic range of the system.  The YCCC system user's manual (Section
12.1) does specify several outboard preamps that could be used.  In a low EMI 
environment, I think they all work fine.  However, at my QTH, with the nearby 
AM BCB station, all of them, without exception, generate increased distortion 
and intermod, which I find unacceptable.

It is always desirable to apply RF gain with a roofing filter in front, which 
is becoming common practice in high performance receivers.  With my K3S 
receiver, the use of a unity gain antenna feedpoint preamplifier is perfectly 
fine if you also turn on the preamp in the K3S.  This gives the best overall 
linear 

Re: Topband: Hi Z amplifiers for 160m

[Michael Tope]

Hi Lee,

Yes, if you are combining coherent signals that are not in phase, then 
the each of the voltage vectors is weighted by cos(phi-i) where phi-i is 
the angle between the i-th voltage vector and the 1st vector. If phi=0, 
then you have the case I described previously. I can see how this can 
get tricky, however, with an electrically short baseline where you are 
striving for cancellation in the rearward looking direction. It's like 
you cancel in the rearward direction and almost cancel in the preferred 
direction :-). This degrades the SNR not because the noise is adding up, 
but because the signals are subtracting down.


73, Mike W4EF.

On 3/11/2020 10:23 PM, Lee STRAHAN wrote:

Mike and all,
   Well stated Mike. It's been a long time since we have conversed. The 
modifier to this is when the signals coming into the combiner are no longer in 
phase or coherent. This as a result of delay lines and time of signal arrival 
at the many elements. Most often in our small portion of a wavelength low 
frequency arrays the combination of signals is subtractive to form a given 
pattern per array dimension. This then lowers the signal to noise ratio. It 
gets pretty complicated to arrive at a noise figure. The only way we have been 
able to do this with amplified arrays is to simulate the array in NEC being 
excited with a known signal many wavelengths away. We can extract the actual 
amplitude and phase of these multi element array signals and then combine them 
mathematically as you have done by example to arrive at a signal gain number 
from signal combination. The noise gain is easy. I say we because I have a 
retired very smart Ham friend in Finland that has helped me through this. I

t h

  as caused me to rethink gain distribution in some of my arrays.
Lee   K7TJR  OR

What matters is the signal-to-noise ratio (SNR). Take the canonical example of 
an ideal 2-port Wilkinson power combiner with in-phase coherent signals of 10 
Vrms applied to each input along with 1 Vrms random thermal noise from the 
respective element amplifiers applied to each input (i.e. each input signal has 
a 20*log(10 Vrms/1 Vrms) = 20dB SNR).

The power loss of the combiner is 3.01 dB [i.e. 10*log(2)], so voltage of each 
signal is attenuated by 1/sqrt(2) = 0.707. Thus, the components of each input 
signal appearing at the output are 7.07 Vrms each and
0.707 for each of the noise inputs.

The signal components add coherently at the combiner output yielding a total 
signal voltage of 14.14 Volts rms. The noise voltages are incoherent, so they 
add as root-sum-square at the output of the combiner. This yields a total noise 
voltage of sqrt(0.707^2 + 0.707^2) =
sqrt(1) = 1.0 Vrms. Thus, the combined noise voltage is unchanged, but the 
signal voltage goes up by sqrt(2).

The SNR of the combined output = 20*log(14.14Vrms/1Vrms) = 23dB, a 3dB 
improvement.

The same things holds for an ideal N-way combiner with equals noise components 
at each input. The noise power at the combined output equals the noise power of 
any of the equal input components (i.e. 0dB gain).

73, Mike W4EF..



On 3/11/2020 7:22 PM, Lee STRAHAN wrote:

 Hello John and all,
 Concerning the adding the noise in a typical array. If the noise was 
coherent or exactly the same signal from each element/amp the summed noise 
would indeed be 8 times. However circuit noise is always random and incoherent 
which causes the summation to be a single noise power times the square root of 
the number of elements assuming equal levels from each amp. In the case of 8 
elements 4.5 dB increase which is no small matter as well. In the case of the 
three elements the noise summation would be about 2.4 dB higher than a single 
element.
Lee  K7TJR  OR

As the designer of the YCCC high impedance feedpoint amplifier, let me address 
some issues related to the design of the YCCC amplifier as well as feedpoint 
amplifiers in general.  If you don't want to read a lot of technical 
gobbledygook, please disregard this message.

The YCCC uses an AD8055 RF amp as the gain element.  As Lee, K7TJF, points out, there are most 
certainly better op amps out there.  However, the AD8055 was the "best" part I could find 
in a DIP-8 package.  The "better" op amps are all SMT parts but given that the YCCC 
preamp was a kit, I intentionally limited the selection to DIP-8 parts that kit builders could work 
with relatively easily on a PCB.  Not everyone is able to do a competent job soldering tiny SMT 
parts.

Within the universe of available RF op amps, tradeoffs must be made in terms of 
noise, linearity, and bandwidth.  The AD8055 is not the lowest noise part but 
it has excellent linearity and plenty of bandwidth for HF use.  At my QTH there 
is an AM BCB station 3 miles away, which makes it a somewhat challenging EMI 
environment.  The decision to run the op amp in a unity gain configuration 
comes down to linear dynamic range.  It is easy to design 

Re: Topband: Hi Z amplifiers for 160m

[Michael Tope]

What matters is the signal-to-noise ratio (SNR). Take the canonical 
example of an ideal 2-port Wilkinson power combiner with in-phase 
coherent signals of 10 Vrms applied to each input along with 1 Vrms 
random thermal noise from the respective element amplifiers applied to 
each input (i.e. each input signal has a 20*log(10 Vrms/1 Vrms) = 20dB 
SNR).


The power loss of the combiner is 3.01 dB [i.e. 10*log(2)], so voltage 
of each signal is attenuated by 1/sqrt(2) = 0.707. Thus, the components 
of each input signal appearing at the output are 7.07 Vrms each and 
0.707 for each of the noise inputs.


The signal components add coherently at the combiner output yielding a 
total signal voltage of 14.14 Volts rms. The noise voltages are 
incoherent, so they add as root-sum-square at the output of the 
combiner. This yields a total noise voltage of sqrt(0.707^2 + 0.707^2) = 
sqrt(1) = 1.0 Vrms. Thus, the combined noise voltage is unchanged, but 
the signal voltage goes up by sqrt(2).


The SNR of the combined output = 20*log(14.14Vrms/1Vrms) = 23dB, a 3dB 
improvement.


The same things holds for an ideal N-way combiner with equals noise 
components at each input. The noise power at the combined output equals 
the noise power of any of the equal input components (i.e. 0dB gain).


73, Mike W4EF..



On 3/11/2020 7:22 PM, Lee STRAHAN wrote:

Hello John and all,
Concerning the adding the noise in a typical array. If the noise was 
coherent or exactly the same signal from each element/amp the summed noise 
would indeed be 8 times. However circuit noise is always random and incoherent 
which causes the summation to be a single noise power times the square root of 
the number of elements assuming equal levels from each amp. In the case of 8 
elements 4.5 dB increase which is no small matter as well. In the case of the 
three elements the noise summation would be about 2.4 dB higher than a single 
element.
Lee  K7TJR  OR

As the designer of the YCCC high impedance feedpoint amplifier, let me address 
some issues related to the design of the YCCC amplifier as well as feedpoint 
amplifiers in general.  If you don't want to read a lot of technical 
gobbledygook, please disregard this message.

The YCCC uses an AD8055 RF amp as the gain element.  As Lee, K7TJF, points out, there are most 
certainly better op amps out there.  However, the AD8055 was the "best" part I could find 
in a DIP-8 package.  The "better" op amps are all SMT parts but given that the YCCC 
preamp was a kit, I intentionally limited the selection to DIP-8 parts that kit builders could work 
with relatively easily on a PCB.  Not everyone is able to do a competent job soldering tiny SMT 
parts.

Within the universe of available RF op amps, tradeoffs must be made in terms of 
noise, linearity, and bandwidth.  The AD8055 is not the lowest noise part but 
it has excellent linearity and plenty of bandwidth for HF use.  At my QTH there 
is an AM BCB station 3 miles away, which makes it a somewhat challenging EMI 
environment.  The decision to run the op amp in a unity gain configuration 
comes down to linear dynamic range.  It is easy to design for more gain, but it 
is also easily demonstrated that you will begin to suffer in terms of unwanted 
intermods.  With the YCCC preamp, I get absolutely zero BCB intermods or 
distortion products in the 160m band at my QTH.

In general I do not like to use an outboard preamplifier between the output of 
the phased array combiner circuit and my receiver because it degrades the 
linear dynamic range of the system.  The YCCC system user's manual (Section
12.1) does specify several outboard preamps that could be used.  In a low EMI 
environment, I think they all work fine.  However, at my QTH, with the nearby 
AM BCB station, all of them, without exception, generate increased distortion 
and intermod, which I find unacceptable.

It is always desirable to apply RF gain with a roofing filter in front, which 
is becoming common practice in high performance receivers.  With my K3S 
receiver, the use of a unity gain antenna feedpoint preamplifier is perfectly 
fine if you also turn on the preamp in the K3S.  This gives the best overall 
linear dynamic range with a preamplified short vertical system.
There is no loss in noise performance because the noise on 160 and 80 is 
totally dominated by atmospheric noise.  In measurements I made at my QTH, the 
internal noise of the YCCC preamp is about 10 dB lower than my daytime 
atmospheric noise on 160m when using a vertical about 20 feet high.

You must also consider the number of active elements in an amplified antenna 
array when evaluating overall system noise performance.  This is because the 
amplifier circuit noise power of all the feedpoint amplifiers is added together 
when the elements are phased up in a combiner.  If you have N elements in your 
array, the effective circuit noise contribution gets multiplied by N.  The YCCC 
array has 3 active 

Re: Topband: 160m VP8PJ

[Michael Tope]

I was hearing them 339 to 559 this evening around 0730 UTC. I may have 
actually worked them. I could tell they came back right away when I 
called them, but the QSB buried their reply. After a couple of tries, I 
heard their reply at ESP level. Then immediately after I stopped 
transmitting my reply, the LID that's been QRMing them threw a carrier 
on top their QRG (c'est la vie). I recorded the QSO, but the audio 
connection between my K3 and the computer I use for remoting the station 
is fouled up, so the recording will probably be no better than fuzzy 
audio I am getting down here in Los Angeles. I need to drive out there 
sometime soon and fix it. It was working pretty good until I pulled the 
computer out to do an "upgrade".


73, Mike W4EF/6.



On 2/24/2020 12:16 PM, Wes wrote:
I listened at my sunset (and theirs) but heard nil even though Bob, 
W7RH, with his big antenna had spotted them. I listened periodically 
over the next couple of hours and finally decided it wasn't going to 
happen.  After a night of TV watching I went to bed about 0600Z 
without bothering to listen again.  Imagine my chagrin to see the 
spots from last night when I looked this morning.  I hope they're on 
again tonight.  I'll be ready.


Wes  N7WS


On 2/24/2020 10:30 AM, David Olean wrote:

Hi Gary,

I was out of the house early in the evening on Sunday, but started 
listening a little before 10 PM local time.  VP8 was very weak and 
mostly in the noise. They would peak up and be readable for short 
periods of 15 seconds or so. Over the next half hour the signal 
started building here. and by 10:30 they were good copy most of the 
time for me. I am 30 miles inland, so no salt water effect. W7RH said 
they had good ears and to call them even if they were weak. I took 
his advice and they came back right away as soon as I called! I was 
so surprised I sent my call again to make sure I was not imagining 
things! It really took me by surprise.  They peaked up 5 hours after 
sunset here. By 0500 UT they were getting sorta loud at times!


I am not sure, but I think many areas had no propagation as there 
were few callers most of the time. I listened up until about 0600 UT 
(1 AM here) It was getting close to EU sunrise but very few European 
callers, and they would call sporadically. There were not so many NA 
callers either, although VP8PJ was making a steady run of contacts.  
Back at 0300 UT I did hear a good pile of EU callers calling VP8 when 
he was impossible copy here.  Later on, there were fewer EU callers.  
If it is a new country, I doubt people would quit for a nap! I heard 
a few comment that VP8 was impossible copy later on.


Then again, maybe everyone was exhausted from the CQ 160 SSB 
weekend.  It was fun to listen as the night progressed, and I was 
amazed at how well VP8PJ was hearing; better than the callers almost 
all the time!


73

Dave K1WHS

On 2/24/2020 6:04 AM, Gary Smith wrote:

VP8PJ, in South Orkney is a 559 here
tonight. A new one on 160 & my only other
S. Orkney Q was on 15M in 1990.

Amazingly it took two calls and he came
back so N/S propagation is excellent right
now.

73,

Gary
KA1J
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Re: Topband: Measuring Common Mode Chokes

[Michael Tope]

On 12/18/2019 3:46 PM, Chuck Hutton wrote:

In the past, I have simply used my N2PK VNA to measure impedance of the choke 
by connecting the shield of the coax to the VNA ports.

Recently I've been discussing common mode chokes with others who have a 
different methodology.
They prefer to do a transmission test through the choke and report the "common mode 
rejection".
This is done by placimg a crossover cable between the VNA output and the choke. 
The choke output is connected in a normal fashion (center to center, shield to 
shield) to the VNA input.

This does not seem ideal to me.
First, the choke is being driven in differential mode rather than common mode.
Second, the measurement depends on (varying) isolation between the coax center 
and shield. So it's not truly common mode rejection.

Am I on thr right track?
A handful of Googles has not netted me any clear summary of test methodology 
for reportimg CMRR. I fimd a small number of tests reportimg impedance.

Chuck


Chuck,

I agree with your assessment of the "crossover cable" method. If 
understand your description correctly, that puts the choke into a 
transformer mode where the shield is the primary and the inner conductor 
is the secondary. IMO, that is not a good way to measure common-mode 
impedance since the common mode impedance will appear in parallel with 
the 50 ohm impedance provided by port 2  of the VNA. In principle, I 
suppose you could de-imbed the common mode impedance from the measured 
S11. In practice, I can't imagine that being very accurate since you are 
trying to de-imbed a very high impedance from a very low impedance. A 
small measurement error, would lead to very large errors in the estimate 
of the commode mode impedance.


Connecting the respective ends of the choke's coax shield to the 
respective center conductors of the two VNA ports is a much better 
method (i.e. VNA_P1--<<--|Zshield|-->>--VNA_P2). In that case the 
magnitude of the S21, (i.e. MS21dB) should equal 20*log[|50/(Z+50)|]. 
For large Z, this simplifies to ~20*log(50/|Z|). Thus, if the magnitude 
of S21 at some frequency is -40dB, then the magnitude of Z at that 
frequency is ~5000 ohms. If you do the math using the phase of S21, you 
should be able resolve the resistive and reactive components of |Z|. I 
think a method similar to this is what K9YC recommends in his app notes 
on ferrite chokes.


73, Mike W4EF.

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Re: Topband: 160 conditions

[Michael Tope]

Thanks for coming back to me, Tom. The only reason I knew the band was 
open is that I was sitting on 1821.0 listening for S01WS who had been 
spotted there. Apparently he was gone because, Eric NO3M, asked if the 
frequency was in use and then started calling CQ. I was surprised to 
hear HB9CAT come back to him with a good signal. I need HB9 on 160 CW, 
so I decided I would try calling CQ at 1820.2 KHz. HB9CAT never answered 
me, but you and a whole string of other stations in the UK answered, all 
with very good signals. I wish my RX situation was better (I was just 
using the TX antenna). A couple of stations called near the end of the 
opening, but I wasn't able to pull out their their full callsigns.


73, Mike W4EF.

On 12/15/2019 12:54 AM, Tom Boucher wrote:

It's nice to hear the band back in good shape again after a few years. Big
CW signal from W4EF in CA this morning along with ZL3IX, also a string of
JAs/HL earlier this week.

Let's keep the 160 CW activity up!

73,
Tom G3OLB


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Re: Topband: COSMIC RAY UPDATE

[Michael Tope]

During the last minimum, there were times when high northern latitude 
stations in zone 17 and 18 would be very strong for long periods of time 
here in southern California. Last Sunday morning during the ARRL 160 
contest there was an opening that had that very low absorption 
characteristic (RA4LW was briefly pumping my AGC), but it was very short 
lived opening. Nothing like the sustained openings from the last cycle.


I've been hoping for a repeat performance of the last cycle, but so far 
I've been disappointed. Perhaps the GCR phenomenon is the reason. We are 
still early into the winter season, so perhaps there is still some hope.


73, Mike W4EF

On 12/14/2019 10:24 AM, Bill Tippett wrote:

This could account for relatively poor conditions on 160 despite the low SF
and K indices:

*COSMIC RAY UPDATE:* Something ironic is happening in Earth’s atmosphere.
Solar activity is low–very low. Yet atmospheric radiation is heading in the
opposite direction. Cosmic rays percolating through the air around us are
at a 5 year high and only percentage points away from a Space Age record.
Find out what's happening on today's edition of Spaceweather.com

.

73,  Bill  W4ZV


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Re: Topband: Relationship Between Ground Wave and Low-Angle Radiation

[Michael Tope]

On 9/13/2019 6:31 AM, N4ZR wrote:
I don't think I've ever read anything on this topic.  Basically, what 
I'm asking is, could ground wave to a fairly nearby Skimmer be used as 
an analogue to low-angle radiation to assess the effectiveness of 
radial systems on an inverted L?  W3LPL is about 30 miles from me and 
has a very capable Skimmer Server-based RBN node.



Hi Pete

Perhaps you could try some RBN tests without changing anything 
significant on either end of the system over a period of time just to 
see if you can get a stable baseline. A transmit beacon on a timer that 
lets it transmit from 11:30 AM to 12:30 PM every day for a month would 
give you a pretty sizeable dataset. Then you could pull down the RBN 
records to see how much variability there was in signal strength over a 
large set of measurements.


73, Mike W4EF..
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Re: Topband: 7P8LB in the “Capital of lightning”

[Michael Tope]

Rune

I made a recording of what you sounded like on the night of March 15 
(UTC) in California. My receive antenna was nothing special - just some 
unknown combination of my transmit antenna (55 ft top-loaded vertical) 
and a 20ft top loaded vertical (one element of a W8JI Rx four square) 
mixed together with a MFJ-1026 noise canceller. I was in a hotel room in 
VE3 operating remotely when I made the recording, so I couldn't check 
the adjustments of the MFJ-1026.


When I first heard you, your signal was so loud I wondered if it might 
be from a pirate. When you faded at your sunrise, however, I knew I was 
dealing with the real thing (or a really clever pirate).


In the recording you'll hear me bouncing back and forth between your Tx 
frequency and the pileup. A truly amazing opening. You (and others) 
should be able to download the recording here:


https://www.dropbox.com/s/f3g2wa1f7bdk9vb/HRD%202019-03-15%207P8LB-SWL%201824r5%200405%20UTC.mp3?dl=0

73, Mike W4EF/6 (& /VE3)..

On 3/19/2019 2:06 PM, Rune Øye wrote:

Dear all,

Thanks for the patient during the 7P8LB operation and particularly on the
TB. This location is a challenge but doable if you have plenty of time. On
the journey from Johannesburg to Lesotho, I experienced one of the heaviest
lightning storms I ever have seen. I then understand that this will be a
challenge and the days ahead conformed this. A lot of effort was done to
get something going on TB but for sure it was not easy. We spent a lot of
time to negotiate with the owners of the land surrounding the lodge, but
when the “deal” is changing from one to the next day, it’s not easy. When
first 160 antenna was up, I got a “standby” to continue our installation
and I had to prepare we written agreement and we basically “lost a day”.
When we finally had the agreement in place, we were ready to install
element number 2 (2 el end fire broadside array) Same day antenna one broke
due to the one of the guy wire pegs broke in a heavy storm and felt down.
Now I had to use antenna number two as spare parts and repair antenna one
and this was done the same day. In the afternoon same day, a horse was
running around and hit the tophat guide wires, but this was reparable. Next
days the 80 meter antenna felt down duo to a horse that was “running in
circle” and hit one the guywire. The antenna did not get any damage and was
an “easy fix”. Installed 2 x VE3DO loops that I phased but no luck since
the loop closest to the lodge was just to noisy. Further I installed a VLB
(very low beverage antenna) 130 meter long and I use a MFJ-1026 noise
cancelling unit to cancel out S8 of the powerline noise from a nearby
powerline. This setup worked somewhat, and I was able to work 100 EU
stations and one JA stations that night. Further Svein LA3BO, managed to
work a few NA stations as well after I went to bed. For the two last days
we decided to prepare a 250 meter long terminated BEV that was laying on
top of the cornfield. New BEV Antenna was now North of the powerline about
50 meter and reduced the Powerline noise a lot.I use the MFJ 1026 to get
rid of the remains of the powerline noise. The following night was the
first night with good wheatear conditions and we had good result to EU, one
JA and a few NA. The last night before we shut down the conditions was not
as good as the day before, one JA station a fair amount of EU and some NA
at our SR. Its frustrating to see the wall of NA stations in the pan
adapter but the signal is just so very marginal and deep QSB. This is what
we were able to this time however, I guess that this location deserves a
topband Expedition only :-) Before I left I got the email address from one
of the owners of the land surrounding the lodge and I also pay him some
money as a thanks you of using his land. The land north of the lodge have
plenty of space for BEV antennas but permission is needed. Our permission
was to install the antenna after darknes and sneak out and take it in just
after day light . Where do we go next, maybe the digit 9 or 2 in the
prefix at the same time as we could do a TB operation in 7P. The clublog
count says 561 QSO CW and  FT8 for 160 meter band.

I am not a native English speaker or writer so apologise for spelling
mistakes and how to build a sentence

73 for now LA7THA / 7P8LB team leader.
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Re: Topband: High voltage insulator

[Michael Tope]

Hi Ray,

I have a 55ft tall aluminum tubing vertical for 160 meters which is 
center loaded with an inductor and top loaded with 4 sloping wires. At 
the top of the tubing vertical I have a yard arm made of a piece of 
aluminum angle stock that holds up a pulley which is offset ~18" from 
the aluminum tubing vertical. From that pulley I am suspending a wire 
vertical for 80 meters in parallel with the 160 meter vertical. Since my 
160 meter vertical is only 55 ft tall, the last 10 ft or so of the 80 
meter wire bends down at the pulley level at an ~45 degree angle.


I am just using standard ~2" long plastic (or perhaps they are porcelain 
- I forget) end insulators at the 55ft level  (the rope going thru the 
pulley attaches to the insulator supporting the wire at the 55 ft level) 
and on the end of the ~66 ft long wire. I have never had any problems 
with these insulators failing when running 1500 watts into this wire 
vertical.


Have you tried leaving the base of the 160 meter vertical open instead 
of shorted? I use an Ameritron RCS-4 at the base of my vertical to 
switch from the 160 meter tubing portion to the 80 meter wire portion. 
The RCS-4 leaves the unused ports open so the base of the 160 meter 
tubing vertical floats when I am 80 meters and vice versa.


If your 160 meter vertical  looks like an ~1/2 wavelength on 80 meters, 
shorting its base may cause the mutually coupled RF from the wire to 
induce a high RF voltage in the tubing near the end of the 80 meter wire 
(it might be worth trying to model this in EZNEC).  In the absence of 
some sort of mutual coupling like that, the voltage at the end of a 1/4 
wave wire vertical shouldn't be any worse than the voltage near the end 
of an 80 meter 1/2 wave dipole and I have never had problems using those 
standard ~2" long plastic or porcelain dipole end insulators on 80 meter 
wire antennas when running legal limit. Of course, I should say that I 
am only at a moderate altitude (~2700 ft ASL) and far away from ocean 
salt spray.


I hope this helps.

73, Mike W4EF...



On 1/31/2018 6:20 PM, Raymond Benny wrote:

I need the experience and wisdom of this group.

I have am 80m vertical hanging off the side of my 160m vertical and share
the common radial system. The 160m vertical is 4" and 3" irrigation pipe,
72 ft tall with 4 - 30ft top hat wires and a loading coil at the base. The
80m vertical is up 68 ft and hangs from a 14" side arms and has its own
coax and loading coil. I have to short the 160m vertical to ground to
operate 80m. I run near 1500w output.

The problem is that the 80m insulator at the top shorts and arcs out over
time. I understand there is perhaps 6 - 10 KV at the top of the 1/4 wave
80m vertical. I can see it now arcing at night and my swr is jumping
between 1.5 to 2.0. My original insulator what just a small, abt 1" x 2"
white porcelain wire insulator that lasted for 2 - 3 years before it
cracked and shorted due to mechanical strains. My second was some sort of
composite insulate about 1" x 4" long that lasted abt a month before it
melted. My last insulator that is arcing, I think it is some sort of
porcelain insulator. Maybe its cracked too.

I am tilting down the vertical tmw to replace the insulator and want to get
some ideas as what to replace it with. I have both white and brown guy wire
insulators, about 1 - 1/2" dia by 3" long, or I'm wondering if a synthetic
material type might work the best. I have three pieces of synthetic rods,
about 3/4 to 1" dia. One is from the center insulator of a yagi driven
insulator from my junk box and about 1" dia by 8" long. I think its
fiberglass, but not sure. I also have from my junk box, one round stock
that might be Delron another and other might be Teflon or some other
synthetic material. I just placed the 3 pieces in the microwave with a cup
of water. After 2 minutes, all three were slightly warm. After a second 2
minutes hit, two of the synthetic types were very hot. The yagi dipole
center insulator which I think is fiberglass was still only slight hot.

So, what conclusions can I deduce? Which one might be best for my use? I'm
tending towards using one of the porcelain insulators.

Any thought or experiences? Are there more tests I can do on the synthetic
material rods?

Tnx for your thoughts and recommendations.

Ray,
N6VR
Near Prescott, AZ




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Re: Topband: English to Russian Translation

[Michael Tope]

Thanks to all who replied with generous offers to help with the 
translation to Russian. I have received the assistance I needed.


Happy New Year to All !

73, Mike W4EF


On 12/25/2017 9:31 PM, Michael Tope wrote:
I am trying to compose an email to a Russian speaking ham in Eastern 
Europe (Kaliningrad) about a Topband QSO from several years ago. I 
composed the letter with Google Translate and was wondering if there 
was a ham fluent in English and Russian who could check the 
translation for me? Let me know off list and I will send you the 
English source text and the output from Google Translate.


73, Mike W4EF..




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Topband: English to Russian Translation

[Michael Tope]

I am trying to compose an email to a Russian speaking ham in Eastern 
Europe (Kaliningrad) about a Topband QSO from several years ago. I 
composed the letter with Google Translate and was wondering if there was 
a ham fluent in English and Russian who could check the translation for 
me? Let me know off list and I will send you the English source text and 
the output from Google Translate.


73, Mike W4EF..




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Re: Topband: Fw: verticals by the sea

[Michael Tope]

Another good example was D4B's 160 meter inverted-V Yagi that was setup 
near the edge of the bluff at the Monteverde contest site (now D4C).


Al put in an incredible topband signal into the west coast of the USA. 
Once when I sent him an email complimenting him on his big signal, he 
wrote back and informed me that his amplifier was broken that weekend so 
he had been running in the low power category. I was totally floored.


ZL8X also had a very good low power signal on topband. I think they were 
using an inverted-V up high in a tree along a cliff overlooking the ocean.


73, Mike W4EF..

On 4/3/2015 10:19 AM, donov...@starpower.net wrote:

Hi Herb,


Stew's two element inverted-V beam was 265 feet above sea level,
a spectacular location. The water tower is on the edge of a steep drop
to the ocean.


73
Frank
W3LPL


- Original Message -

From: Herbert Schoenbohm he...@vitelcom.net
To: topband@contesting.com
Sent: Friday, April 3, 2015 4:24:19 PM
Subject: Re: Topband: Fw: verticals by the sea

Didn't Stew Perry, W1BB have basically and inverted Vee with open wire
feeders at his famous Lighthouse QTH at Winthrop, MA?

On 4/3/2015 12:48 PM, k1fz wrote:



Years ago there was someone using an inverted V and doing quite well with
DX. It was later found that he had a long vertical open wire feed line
that was thought to be acting as vertical antenna.

73
Bruce-K1FZ


- Original Message - From: Mike Smith VE9AA ve...@nbnet.nb.ca
To: topband@contesting.com
Sent: Friday, April 03, 2015 10:17 AM
Subject: Re: Topband: verticals by the sea



Is there any advantage to using an inverted VEE by the sea? Didn't I
read
inverted VEEs had a lot of vertical polarization?

Reason I ask is I plan to do the IOTA contest on an Island in NB or
NS and
have not yet decided on an antenna.



Thanks,


Mike VE9AA
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Re: Topband: Remote now DXCC??

[Michael Tope]

Doug,

I don't think using remotes in different countries would be permitted 
even under the most liberal interpretation of the new ARRL DXCC rules. 
As far as I know, for example, using the RHR site in Sicily would 
require me to sign IT9/W4EF. If I were to simply sign W4EF, I would 
likely not be in compliance with Sicilian telecommunications law. If I 
tried to submit a QSL made out to IT9/W4EF, for my US DXCC, it would not 
count since clearly the contact was not made from a transmitter located 
in the continental United States. Thus, to make use of a remote in a 
different country to gain an advantage in the ARRL awards program, 
requires more than an ethical breach. It requires breaking the law since 
I would have to sign W4EF when using the IT9 remote to pull it off. .


73 Mike W4EF...

On 2/27/2015 1:07 PM, Doug Renwick wrote:

-*** Let me help out here.  I have gone on record in past postings that I
personally do NOT have a problem with remote operations in the vicinity of
their home station.  The problem is people using remotes in different
countries and on different sides of the continent to inflate their
standings.

Doug
As to this specific thing; If someone is in another country close to
rare DX, visits a ham and uses their station and then uses their own
home call when making the easy Q, that's cheating. This kind of
cheating has been possible all along, it may make it easier with
today's technology.

I never worked Don Miller but I did work Romeo, both DXers were
notorious for supposedly claiming to be where they weren't  slews of
people worked them feeling they worked a legit operation. I worked
Romeo in 91 as XY0RR and got his QSL  it counted for DXCC. Once I
heard the flap about his operation, I didn't feel I fairly worked
Myanmar until I got confirmation from XZ1J for a Q in 2013.

People have been claiming DXCC credit unfairly and giving it for
years. RHR will not make anything new happen. I just sent something
offlist to one of us and I agree with what I said... As to people
not doing the right thing with a tool, that's been happening since
those apes hit each other with femurs in the opening scene in the
movie 2001.

Or as the Who said in We won't get fooled again: Meet the new Boss,
same as the old Boss.

People have been cooking the books for years  someone always will
be; hasn't stopped me from having fun for 35+ years.

73,

Gary
KA1J


---
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Re: Topband: Rules vs. Ethics (was Brave New World)

[Michael Tope]

Larry, you hit upon a very important point regarding ethical lapses not 
being entirely victimless. Personally, I feel very strongly that when I 
send a QSL to someone it should indicate the state, county, and grid 
square where my station was located at the time of the contact. If my 
QSL or LOTW confirmation says I was in Los Angeles County, I better have 
been in Los Angeles County so that the recipient of my QSL has a valid 
confirmation of a QSO with Los Angeles County. I've done several 
portable operations and guest operator stints over the past ten years, 
and I have gone to great pains to make sure I provided accurate 
confirmations for those operations. This required creating different 
location signatures in LOTW and keeping track of which QSOs go with 
which locations. Same thing for physical QSLs. It would have been a lot 
less work to use the same QSL data for all my contacts, but that would 
have meant sending out QSL cards or LOTW confirmations with bogus 
location data. I thought about taking the easy road, but that would have 
really bothered me. I wouldn't want a county hunter to get a card from 
me that says Los Angeles County when in fact I was in Riverside County 
when I made the QSO. The same things applies to CQ Zone or State.


If someone is using a remote station, I think they have an ethical 
responsibility to provide confirmations which reflect the location of 
their transmitter at the time of the contact. If they want to use 
remotes all over the country to work their DXCC awards, that is there 
business, I don't really care. If on the other hand I got a card from a 
guy in Alabama that I needed for some award (e.g. 5BWAS) only to find 
out later that although he was physically located in Alabama, he was 
actually using a remote transmitter located in Utah when he worked me, I 
would be very upset.


BTW, full disclosure, I use an internet remote HF station. It has been a 
lot of fun building up the station and then remoting the equipment. It 
allows me to live in this horrible radio location shadowed by tall 
mountains but with a short commute to work while at the same time 
enjoying a decent radio QTH (flat terrain and room for antennas) without 
having to drive 2 hours round trip every time I want to use it. Of 
course, both my home QTH and the remote QTH are in the same county and 
grid square, so there are no worries about having multiple QSLs to keep 
track of.


73, Mike W4EF

f someone wants to
On 2/26/2015 1:45 PM, Larry Burke wrote:

Except it is not an ABUSE of the rules.  People feel that it is an abuse
but it is fully sanctioned by the ARRL.

  


Jim stated as much in the note to which you are replying.

  


What is in play here is the difference between laws/rules and ethics. Just
because something is legal does not make it ethical.  Adultery is not a
crime in 29 states of the United States or most of the industrialized world.
Is it therefore ethical? Is it ethical to click between remotes on the east
and west coast because DXCC rules permit it? Throwing their hands up, the
League is leaving the answer to the last question up to the individual
operator. Why, if such operations are so ethically pure would one commercial
remote business advertise completely anonymous operation? The very nature
of the wording suggests their service is the ham radio version of the
No-Tell Motel.

  


With regards to the how I got my award shouldn't matter to anyone else,
I'd argue that the operator on the other end of an unethical contact can
be affected. There's a fair chance that he is pursuing an award as well. An
operator in EU pursuing WAS (or VUCC on 6m) may work a W7 who is using a
remote -- commercial or otherwise -- and does not indicate the location of
the actual transmitter. The EU op goes away thinking he worked Oregon. Lo
and behold the LoTW match or paper card shows up and confirms he did.
There are a couple of west coast stations who routinely use east coast
remotes to work EU on 6m and use their home state and grid square in the
exchange. A savvy op on the other end can often tell if the exchange is
legit, but there are strange spotlight openings on that band, just as there
are on Topband. These ethical lapses are not entirely victimless.

  

  


Larry K5RK

  

  

  

  


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Re: Topband: Modeling the proverbial vertical on a beach

[Michael Tope]

On 8/15/2014 6:51 AM, Tom W8JI wrote:


For receiving, an absence of noise sources in the path is all the 
difference in the world. As an example of this look at what N7JW and 
K7CA did from the Utah desert area. Utah desert is like the 
anti-saltwater, and they are located much further from Europe than the 
east coast with a worse polar area path, yet they had outstanding 
results. Saltwater has the same advantage, as do freshwater bodies, of 
a lack of noise sources in what might be a desired direction.


For efficiency (which only affects transmitting), the advantage is 
primarily concentrated at low angles and primarily affects vertically 
polarized systems. The question then becomes one of wave angle and 
polarization.


Then there is distance as a factor, and path loss related to the 
magnetic poles, which are factors.


A good station has a combination of everything going for it, but there 
is no magic and there certainly isn't any 10 dB or more involved just 
from being near saltwater. A few dB here and there from multiple 
factors are what make the difference. Move 25% or 50% closer, get rid 
of noise sources in the path, increase vertical antenna performance at 
low angles a few dB, and get away from going past the magnetic poles 
and it is a winner. It isn't from magic, and it isn't all from the 
presence of saltwater, and it is not 10-20 dB by any stretch of the 
imagination.


73 Tom


I agree with what you say, Tom, but as others have pointed out, this 
still leaves the door open for an advantage at very low takeoff angles. 
A mostly unexploited propagation mode at very low takeoff angles could 
explain all the anecdotes from mobile operators which describe signals 
peaking as they drove up to waters edge and fading as they moved away. 
Also, this hypothesized low-takeoff propagation mode isn't necessarily 
at odds with the sunset/sunrise high angle mode (low dipole suddenly 
beats the vertical) that many have observed (IIRC, yourself among them). 
Myself I can imagine two distinct propagation modes, one at high angles 
and one at very long angles. They could, but wouldn't necessarily occur 
at the same time. What is needed is a really good test protocol and 
someone willing to do the work necessary to follow it.


73, Mike W4EF.


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Re: Topband: Modeling the proverbial vertical on a beach

[Michael Tope]

On 8/13/2014 6:28 PM, Tom W8JI wrote:




But skimmer, which displays a relative level, does not show the level 
difference.


Skimmer shows about the same peak levels, but the stations closer or 
over salt water paths (not localized salt water) have longer openings 
but no more level for peak level. Anyone can look at that.


K3LR is about as strong into Europe, when I look at skimmer levels, as 
someone on the coast.


The exceptions are people right next door to Europe (like VY1).


73 Tom


Tom,

How much skimmer data did you mine before establishing a firm conclusion 
that the advantages of saltwater proximity are exaggerated?


Myself, I think of how well AA7JV and HA7RY have done at various 
locations using antennas that were very close to or in some cases 
literally in the saltwater. The consistency of their topband signals 
compared to Dxpeditions who were confined to inland locations seems to 
point to a big advantage. I'll admit, however, that this hypotheses 
comes about from anecdotal observations filtered through a mental lens 
that is biased towards believing saltwater is a huge advantage.


I think using skimmer is an excellent approach to this question provided 
of course that you have mined enough data to filter out the statistical 
noise.


73, Mike W4EF...

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Re: Topband: VK3ZL SK today

[Michael Tope]

I am very sad to hear this news. There are some things you count on in 
life. The sun rises every morning and then sets in the evening; and back 
when I was really active on topband and up every morning at some 
insanely early hour, it was just a given that Bobby was lurking there 
somewhere in the noise.


I just looked in my log and my first QSO with Bobby was on July 15, 
2003. I had only been in this house for less than a year and I think my 
topband antenna was still an 80 meter inverted-V hung on a 40 foot Rohn 
push-up mast lashed to the side of the house with the coax shield and 
center conductor tied together and fed against a ground rod. On many an 
early morning in those days, I would listen to Tom W8JI keeping his 
daily sked with Bobby. Those were some really good times for me, so I am 
truly sad to know that Bobby will no longer part of my early morning 
topband landscape, except in fond memory.


Rest in peace, dear Bobby.

73, Mike W4EF/6
Tujunga, Ca

On 7/8/2014 6:56 AM, Dan Edward Dba East edwards wrote:

I too will surely miss bobby;  we had a lot of fun making contacts almost all 
summer long, for several
  seasons.  He nearly always heard my 'wet string' short tx marconi. His 
expertise with GS35b's was well  established,  and he shared freely all 
relevant technical advice.

RIP VK3ZLW5XZ, dan



On Tuesday, July 8, 2014 8:21 AM, W2PM via Topband topband@contesting.com 
wrote:



RIP And 73 Bob.  Some of the best qsos on 160. Copied his top hat design.  Gone 
but not forgotten.

Sent from my iPhone


On Jul 8, 2014, at 1:15 PM, dl8yhrfrank--- via Topband topband@contesting.com 
wrote:

RIP BOB
Best wishesyou was a great operator...
vy 73
Frank






-Ursprüngliche Mitteilung-
Von: Eduardo Araujo via Topband lt;topband@contesting.comgt;
An: Topband List lt;topband@contesting.comgt;
Verschickt: Di, 8 Jul 2014 5:44 am
Betreff: Re: Topband: VK3ZL SK today




Very sad news indeed.

We will miss you Bob. Rest In Peace

Eddie, LU2DKT






-Mensaje original-
De: Topband [mailto:topband-boun...@contesting.com] En nombre de LB3RE LJ3RE
Stein-Roar Brobakken
Enviado el: lunes, 07 de julio de 2014 11:12 p.m.
Para: David Raymond
CC: topband@contesting.com; SidShusterman; robert briggs; Jean Briggs;
K3JJG; t...@kkn.net; Bob Garrett; Bernie McClenny, W3UR
Asunto: Re: Topband: VK3ZL SK today

Sad to hear this.He was always on the topband and made it clear that the
band was open, he will be missed. 73s SK

---Sent by iphoneLB3RE LJ3RE K3RAG ex: LA6FJAwww.lb3re.com ~ Rag ~ Stein
Roar Brobakken
e-mail:post@lb3re.comhttp://la5o.wordpress.comwww.contesting.no

Bob was truly a remarkable person.  Not only did his homebrew skills far
surpass the vast majority of us but he also put out a remarkable signal with
a modest station.  A lot of topbanders may be unaware that Bob's signal came
from a homebrew 42' vertical (yes, forty two foot) .  Capped off with a
hefty top hat and a very good ground radial system, he was able to work the
world daily.  He and I had other shared interests and enjoyed exchanging
emails.  I will surely miss his friendship and his signal on 1824.5 on those
cold, winter morns.



73 Bob. . .rest in peace OM.



Dave, W0FLS

- Original Message -
From: SidShusterman
To: topband@contesting.com ; Jean Briggs ; robert briggs ; Bernie
McClenny, W3UR ; Bob Garrett ; K3JJG ; David Raymond ; t...@kkn.net
Sent: Monday, July 07, 2014 6:23 PM

Subject: VK3ZL SK today





I received an email from Jeannie this afternoon. Bob succumbed to the
effects of bladder cancer today. Bob was  many things. He was one heck of a
builder.  His amplifiers won the SERG homebrew competition so many times
that they finally gave him a lifetime achievement award.  He was a fixture
on TopBand and gave many their first VK QSO. He was also a beacon until
recently.  If there was any propagation at all Bob was there to work it.

Over the years Bob and I and I am sure some others developed a
relationship that transcended ham radio. I found that Bob was a fire
communications officer who provided essential communications and control for
the intense fires that happen in that part of Australia amongst other
interests.

Above all Bob was our friend.
Bob told Jeannie his wife  he wanted the following on his grave marker:

Robert William Briggs..

..loving husband of Jeannie..

..17 Oct 1942 ---7 July 2014..

...vk3zl   s k..

and that is what she will do.
Jeannie can receive your emails at both her email address: Jean Briggs
lt;jab...@bigpond.comgt;

and also she is keeping Bob's account open: vk...@bigpond.com

Sid K3SX





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Re: Topband: Beverage feedline

[Michael Tope]

Timo,

According to ARRL's TLW program, your RF insertion loss for 1500ft of 
RG-6 cable should be around 7dB. This is based on Belden 8215 which uses 
a solid dielectric which makes it more lossy than your 1189A which is a 
foamed dielectric, but less lossy than 1189A because it uses a copper 
shield whereas 1189A uses an aluminum shield. These two opposing factors 
seems to balance out as TLW predicts about 10% greater loss for 8215 
than does the loss vs frequency table on the 1189A data sheet, so if 
anything 1500ft of 1189A at 1.8 MHz might be a bit better than the same 
length of 8215.


If you want to run DC thru this cable to power a switch or pre-amp, the 
loop resistance (inner conductor + shield) for 1500ft will be around 49 
ohms. For a 100mA load that will be ~5 volts of drop between the source 
and load.


FWIW, 1189A doesn't appear to be rated for outdoor use whereas 8215 is 
rated for direct burial. OTOH, 8215 uses an all copper shield so its 
probably very expensive compared to the aluminum shield cable (like 
1189A) used by the CATV industry.


I buy 1000' rolls of Commscope F660BEF Gel Coated Direct Bury RG6 from 
these guys for $48 US per roll (I think this is the same stuff 
recommended by W8JI):


http://www.ebay.com/itm/CommScope-F660BEF-Direct-Burial-RG6-Cable-Flooded-Coaxial-Undeground-Gel-Coated-/160693197034?pt=US_Video_Cables_Adaptershash=item256a0f98ea#shpCntId

It looks like they ship to Finland if the overseas shipping doesn't 
raise the price too much (UPS shipping is $25 just to go a few miles 
from Phat's warehouse to my door here in Los Angeles). Perhaps there is 
a cableTV/satellite distributor closer to Finland with better terms.


73, Mike W4EF.

On 6/26/2014 8:12 AM, Timo Korhonen wrote:

Hi all,

We are putting up new beverages for 160/80 at OH5Z.
I have a question regarding the feedline. We have to make
quite long runs like 1500 feet.
When looking for a low cost 75 ohm coaxial I found a Belden
RG6 type cable which is reasonably priced.

Here is a link for technical data

http://www.farnell.com/datasheets/1733139.pdf

This cable has a copper covered steel inner conductor.
Is this an issue on low frequency like 1.8 MHz with long runs like 
1500 feet?


Thanks for your help

73, Timo OG9X
oh5z.wordpress.com

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Re: Topband: Feeding 160M Vertical on 80M

[Michael Tope]

On 1/6/2014 7:18 PM, Bob K6ZZ wrote:

Folks,

I have a 60' tall top loaded vertical for 160M and would like to know how
best to feed it to use it on 80M as well.  On 80M there will be some pretty
high voltages at the feedpoint.

Other than dealing with high voltages, is doing this a bad idea (or good
idea) for any partcular reason(s)?  The high current point would be higher
above ground which seems beneficial at the very least.

What would be the best method for matching it on 80M?

Do 1/2 wavelength ground mounted verticals require the same quality ground
radial system that 1/4 wavelength verticals require?

Thanks and HNY to all!

73, Bob K6ZZ


Bob,

I have a 56' top loaded vertical for 160 meters (it also has some 
inductive center loading) which was built from parts from a Gap Voyager. 
I wanted to use the antenna on 80 meters, but I didn't want to mess the 
possibility of matching a really high input impedance, so to keep things 
simple, I put a short yardarm at the top with a pulley (~ 2ft offset). I 
use the pulley to pull up a separate parallel vertical wire for 80 
meters. It includes a single short top-hat wire beyond the pulley 
insulator which I pull away at an angle to bring the parallel wire into 
resonance on 80 meters. I use an Ameritron RCS-4 four port remote switch 
at the base of the antenna to switch between the 160 meter feed which 
goes through a 1:4 Unun (12.5 to 50 ohms) and the 80 meter vertical wire 
which is direct feed. I have a pretty extensive radial system under the 
antenna (~50 radials 100 to 125ft long). The system seems to work 
reasonably well on both bands.


73, Mike W4EF/6...


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Re: Topband: Insulator problems- Notr og caution

[Michael Tope]

On 12/16/2013 5:52 PM, GeorgeWallner wrote:


On Mon, 16 Dec 2013 14:32:41 -0500
 Charlie Cunningham charlie-cunning...@nc.rr.com wrote:
Many black plastics are blackened by the addition of carbon black 
that
can make them rather lossy at RF!  Been there, done that in my work 
- at

900 MHz.


I have been using 3 black Derlin (Acetal)insulators at the base of my 
160 m vertical. Because the antenna is only 91 foot tall, there are 
substantial voltages on the insulators at legal limit. Indeed, one 
them caught fire just after a rain-shower, when water got between the 
insulator and the metal. I replaced the burned insulator with the a 
new one and covered all the insulators with high voltage putty. That 
was about two years ago and I had zero trouble with any of them since.


George
AA7JV


Hi George,

I had the same experience with black delrin insulators for one of my 160 
meter vertical antennas. It was fine until it got wet, then forget it, 
it would breakdown. I kludged up a shroud to keep the rain off it. It's 
been fine ever since.


BTW, I have never heard of high voltage putty. Where do you get it?

73, Mike W4EF.

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Re: Topband: Beverage antenna terminations

[Michael Tope]

On 9/24/2013 6:05 PM, Tom W8JI wrote:
They were supposed to be non-inductive carbon, but need to find 
something better like carbon film.




Any resistor except a big wire wound is non-inductive on a low 
frequency like 160.


What you want is a composition type resistor, either metal or carbon, 
to handle surges without changing value.


The last thing you want is a film resistor, which is what you probably 
have right now. Carbon films or metal films increase in value after 
short duration high energy surges, because the surge blows part of the 
film layer away. 


Bruce,

If you have any trouble finding the carbon composition resistors that 
Tom is recommending, Ohmite's OX/OY Series Ceramic Composition 
resistors are surge rated and readily available from various electronics 
distributors (i.e. Mouser, Digi-Key, etc):


www.ohmite.com/cat/res_ox_oy.pdf‎

73, Mike W4EF..




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Topband Reflector

Re: Topband: 160M Rhombics

[Michael Tope]

On 7/27/2013 3:23 AM, Bill Tippett wrote:

W0BTU:

 For whatever reason, there's what seems to be a lot of hype about 
W6AM's

rhombics. Such as:

The W6AM station was legendary around the world. Don could beat you in a
pileup for some obscure African station no matter what band, and even if
you were on the east coast. And him in Southern California.

Don was #1 on ARRL's DXCC Honor Roll, and you didn't argue. No matter
where you were, no matter what you were running, Don had beaten you in a
pileup. More than once.

 Beat anyone on the east coast to Europe from California every time? I'm
sorry, but a rhombic is just not that good, even if you DO have one 
pointed

at every direction of the compass as W6AM did.

Absolutely a lot hype, as you stated.  The real King of the 
Hill in those days was Frank Lucas W3CRA:




A old friend of mine told me that he use to regularly beat W6AM in 
pileups with a long boom 20M monobander at 70ft from a small city lot in 
Los Angeles. I think he was running a tetrode with handles, but from 
what I hear about W6AM that wasn't necessarily an unfair advantage :-)


With regard to the impact of favorable terrain, N6NB tells some good 
stories about running QRP class in DX contests from his mountaintop QTH 
in Tehachapi, Ca and all the accusations of cheating that would come his 
way as result.


73, Mike W4EF/6 (whose amp is so small it doesn't have handles, let 
alone the tubes in it)...


_
Topband Reflector

Re: Topband: Problem with compression F connectors on Quad RG-6

[Michael Tope]

On 5/7/2013 7:33 AM, Paul Christensen wrote:
The standard drop cable is a bonded foil with single braid, it has 
been that way since the late 1970's. The current best grade is 
Brightwire by CommScope. Any good cable will far exceed FCC specs 
without a quad shield.


It remained that way with Comcast  ATT Broadband at least until 2002 
when I left ATT corporate engineering, shortly after the merger.  I 
doubt much has changed since then.


Concerns are a bit different in the broadband world where downstream 
leakage must be minimized between 50 MHz - 1 GHz.  The upstream path 
is in HF region, but no sane cable operator uses spectrum below about 
10 MHz.  The only services anywhere near that area of spectrum are 
used for data transponders and IPPV from the set-top box where 
modulation is almost always QPSK.  Telephony and DOCSIS cable modem 
service is all relegated to an area above 20 MHz.  In the Jacksonville 
Comcast system, it's now all above 30 MHz which was made possible 
through the use of tighter diplexer specs in the system amps and 
fiber-optic nodes.  if you could see a spectrum analyzer display of 
the return path back at the headend, you would be amazed that the 
return path works at all. Any point of ingress results high levels of 
interference, most notably SWBC.


I recall writing up a paper in the mid-'90s that predicted a need for 
better return path certification and an upward move of the lowest 
usable frequency to well above 20 MHz.  I pointed to the 11-year 
sunspot cycle as an important driver.  The non-ham engineers in our 
group didn't get it.  But the CTO of MediaOne was a ham, and he did 
get it.  The public did not know it, but there was a real fear between 
1995 and 2000 that return path broadband technology would never work.  
When you consider all the points of potential failure, especially on a 
power-passing system, it truly is a miracle that it works at all.  
Consider this: The typical fiber-optic node services between 200-500 
home passings.  From the comfort of your living room, and with an RF 
signal generator, one can wipe out an entire service area when the 
return path frequencies of the system are known.  This isn't 
theoretical, I demonstrated the impact to a sober group of engineers 
with an Eico generator.  That potential still exists today.


Concerning SANS connectors and wiring, I would take the lead from the 
cable operators.  They cannot afford to have unreliable cables 
anywhere between the customer equipment and the headend or hub 
facilities.  When you've got thousands of miles of cable plant and 
interfacing hardware, that becomes the most important piece in the 
network.  If a router, modulator or fiber amp fails in the system, the 
fix is easy with money.  But if you deploy bad cable and hardware into 
a system, you'll feel the pain a long time as it affects long-term 
service call volume, unhappy customers, and angry government leaders 
who generally hate the cable operators.


Paul, W9AC



About six months ago, our garbage truck hit the sagging telephone/CATV 
drops that serve my house and my neighbor's. It took several days to get 
a response from Time Warner despite the fact that the cable was hanging 
at neck level at times (we pulled it up the best we could only to see it 
get knocked down again by the various delivery trucks that come through 
the neighborhood). In any case, when Time Warner finally responded, I 
saved the discarded drop cable and took it up to my station in the 
desert north of here. I didn't pay close attention to it at the time, 
but this discussion got me to wondering what sort of shielding was used 
in that drop cable, so I retrieved some last time I was up there. This 
evening I took a close look at it.


The drop cable is Times Fiber Communications (TFC/Amphenol) T10 
Teledrop. It look like an RG6 (I didn't measure the diameter) paired 
with a messenger on one side and a telephone twisted pair on the other. 
The coax is tri-shield (bonded inner tape layer, braid, and outer tape 
layer). There also appears to be some sort of sticky flooding compound 
which may be TFC's Lifetime non-drip/non-leak flooding compound (see 
page 85 of the following):


http://www.timesfiber.com/TFC_Cable_Book_III.pdf

The other interesting information in the TFC Cable Book III is Technical 
Note 1025 Drop-Cable Transfer Impedance starting on page 70. What this 
note says is that you can't ignore cable aging due to flexure and 
corrosion when looking at shielding effectiveness. Comparing the 
shielding effectiveness at beginning of life (BOL) can yield vastly 
different conclusion compared with shielding effectiveness done on cable 
that has experienced significant environmental exposure. Quad shield 
seems to have been developed to address the problems that come from foil 
seam separation that occurs as the result of drop cable flexing. It's 
actually a pretty complicated trade space which may explain some of the 
lack of consensus in 

Re: Topband: Problem with compression F connectors on Quad RG-6

[Michael Tope]

On 5/7/2013 7:55 PM, Tom W8JI wrote:


LMR400 or any cable, in sensitive applications, requires a solid bond 
to the shield that carries the vast majority of return current. In the 
case of almost all cables on HF and higher, that is the innermost 
foil. Of course it is different at audio or lower frequencies.


One common connector problem comes from not forcing the woven shield 
tight against the foil at the connector, or having the foil or woven 
shield tarnish or corrode. The path to the inside of the foil is out 
on the braid to an eventual contact point, then back on the outside of 
the foil to the foil edge. At the edge current can go inside.  This is 
like adding 2X the length of the path to the connection point in 
overall shield connection path length.


(Current can also get in across the edge of a longitudinal seam, if 
the seam's overlap is insulated. The problem with that is the seam can 
kill UHF performance.)



If you solder to the shield of LMR400, and put it on a network 
analyzer and measure the stub characteristics, many times (not 
always) it will move around as the cable is flexed. This is because 
the soldering heat contracts the dielectric, releasing pressure 
between the braid overlay and the foil. Now you have a crummy 
connection that changes electrical length of the connection to the 
real shield.


Even if you do things right, once the foil and braid develop an oxide 
layer the connection goes away. This can work its way out for several 
feet of cable length, really messing up a cable. This will not show 
with a single shield.


Cables with foil have to be installed and treated correctly. The more 
layers you add, the more careful we must be. Since the extra layers 
are pretty much meaningless, the best practice is to avoid them. Use a 
good shield against the center and connect to it at the connector.




Tom,

I'll have to admit that I haven't given this much thought, but what you 
are saying about the foil to braid contact makes perfect sense. I do 
recall one friend who is a rabid VHF/UHF repeater builder complaining 
that LMR-400 has issues with IMD. Perhaps this is why. Can you recommend 
a source for a good LMR-400 crimp connectors and the corresponding 
installation tools? To date I've been soldering PL-259s on all the 
LMR-400 I've used as if it were regular single shield RG8. I haven't had 
any hard failures, but clearly there is some risk to doing this 
depending on the application. In fact I do recall some phantom 
inter-station QRM that would come and go when we had an SO2R setup 
running at W6UE some years back. Some of the coax used in that setup was 
LMR-400 with soldered PL-259s.


73, Mike W4EF.

All good topband ops know how to put up a beverage at night.
_
Topband Reflector

Re: Topband: How does KP4KE do it with 20 watts?

[Michael Tope]

He claims he is using a 4 element vertical beam to Europe. An 
optimized 4 EL array combined with proximity to saltwater might explain 
it, but that still seems like a big stretch. I remember sending an email 
to Ed @ D4B remarking on how loud he was here in W6 during one contest 
where he was active. He wrote back saying that his amplifier had died 
and that he was running low power during the entire contest. I couldn't 
believe it. Still going from 1500 Watts to 20 Watts is an 18.8dB 
deficit. That's a lot of dBs to overcome with antenna and QTH. 
Extraordinary claims demand extraordinary evidence. Seems like he should 
step up and provide a detailed description of his antenna system and 
QTH. Barring that, one is really left to wonder.


BTW, here is what K2KW was able to do with a single vertical on the 
beach with 5W during CQ WW CW 2003:


http://www.k2kw.com/6y0aqrp/

20W would be 6dB louder. Add gain from a 4 element array and good 
conditions then it might be possible to explain it given the great 
advantage of CW over SSB on topband. Of course K2KW made no secret of 
his antenna system and QTH. Same thing with D4B.


73, Mike W4EF.

On 3/3/2013 2:31 PM, Herb Schoenbohm wrote:
Really, if his claims are true KP4KE worked 49 countries in two nights 
during the CQ 160 meter contest running only 20 watts. He claims he is 
using for the states a double bazooka at 85 feet. His signals on RBN 
were consistently stronger than my 1.5 KW to a 1/4 wave vertical with 
60 radials.  In fact he was stronger here than Perdro, NP4A who has an 
excellent low band setup with ample power output.  My point is that if 
there some sort of magic antenna that can do this I think it would 
be important to do an forensic analysis of it's structure. As far a I 
can understand such a feat is unprecedented on 160 meter SSB and 
TB'ers might be interested in examining such an an antenna that you 
can hang at 85 feet and be the top dog on the band.


Please let me know when you know if there is true RF magic on 160 meters.


Herb Schoenbohm, KV4FZ


Call: KP4KE
Operator(s): KP4KE
Station: KP4KE

Class: Single Op LP
QTH: Puerto Rico
Operating Time (hrs): 14

Summary:
Total:  QSOs = 508  State/Prov = 49  Countries = 49  Total Score = 
318,794


Club: Rhein Ruhr DX Association

Comments:

[log removed from comments]

Hello, from Aguadilla PR
*Working the contest with 20 watts was fun.*
my Antennas are 4 el. vertical beam looking to EU and  two inverter L 
and  a
double bazooka at 85 feet high to the USA  but conditions no good to 
USA  but

to EU very good opening both day
my goal was 50 countries but only made 49  and  49  State and Canada
No activities from central america and a lot of islands in the 
caribbean with

no operators.
I receive very good reports from EU station.
I think I was the only KP4 Station early on band both days that help a 
lot

Sorry for delay in send this report but no internet in shack.

See you in next contest

73  DX  and remember put your money in ant. no in power hi hi.
Good ham operator no need power.


_
Topband Reflector





_
Topband Reflector

Re: Topband: A 160 Meter antenne puzzle

[Michael Tope]

Glenn,

The impedance of the very short element at the point where it attaches 
to the 4x4 is very high (i.e. very high capacitive reactance).  When you 
stick your hand on the 4x4 you are adding the impedance of your 
hand/body in parallel with a very high capacitive reactance (i.e. the 
equivalent of a very small value capacitor). That is why you see such a 
large change in VSWR when you touch the wood. It also explains why you 
don't see a change in the 8MHz self-resonance of the element. At that 
frequency the element impedance where it attaches to the wood is very 
low (probably 15 to 30 ohms resistive). The impedance of your finger in 
parallel with that only makes a miniscule change, so hence there is no 
visible shift in element self-resonance.


Everything you are observing seems reasonable to me. I wouldn't be 
concerned.


73, Mike W4EF...

On 1/7/2013 6:30 PM, Glenn Biggerstaff wrote:

Hi everybody and happy new year .
I have what I think is an interesting  antenna riddle . I have some receive  antenna verticals (4) that are selected by relays in pair and the pair is fed back to the shack to a phasing boxing .Each antenna is AL tubing about 30 feet tall, base loaded with an inductor and a resistor very much like ON4UN has for his 4 square receive  array .There is a 1 to 1 balun between the antenna and the feed line . The tubing is insulated  with an eight inch length of pvc pipe from  the 4x4 that supports it .The overlap between the tubing and the 4x4 is about eight inches as well . I was doing some testing today and discovered that touching the 4x4 at the top caused the swr to increase from about 1.2 to 1 to 1.7 to 1 . The lower on the 4x4 I touch the less the effect . I am only moving my finger a fraction of an inch and my hand not at all when this happens .The feed lines are disconnected when this is going on .There is no dc continuity between the antenna and any mounting hardware or 

th

  e post .I disconnected the base loading and put  the analyzer on it and it is 
resonant at about 8 mhz and touching the post causes no change with this setup 
. There are eight 30 foot radials laying on the ground and a 2 inch wide copper 
strap about 3 foot long  in the hole that the 4x4 is in .
What is going on here and should I make an effort to limit the coupling between 
the 4x4 and the antenna?


73 , Glenn WW4B
_
Topband Reflector






_
Topband Reflector

Re: Topband: Fw: GAP VERTICAL QUESTION

[Michael Tope]

On 12/15/2012 7:59 AM, DAVID CUTHBERT wrote:
Mike that QTH looks alot like the Great Salt Lake of Utah where I have 
operated a few 160 meter 'tests running a balloon vertical.


 Dave WX7G

I learned about this QTH from Earl K6SE (SK). The terrain to the north 
isn't so great (high mountains), but toward CONUS is literally miles of 
salty lake bed. Also, it was pretty wet the year I was there (2006) 
which I am sure didn't hurt matters. I am glad I wasn't using a balloon 
antenna, however, because the winds got so bad Saturday night of the 
contest it broke one of the ridge poles on my little operating tent. The 
wind then had that broken side of the tent pinning me against the 
operating table :-)


73, Mike W4EF...

___
Topband reflector - topband@contesting.com

Re: Topband: Fw: GAP VERTICAL QUESTION

[Michael Tope]

On 12/13/2012 3:14 PM, Tom W8JI wrote:
Somehow they thought moving the feedpoint eliminated the need for 
radials with an electrically short antenna, when the real mechanism 
was a 1/2 wave vertical was converted to a 1/4 wave groundplane 1/4 
wave above ground and it only got a tiny bit weaker. The groundplane 
still had 8 radials, but they were hundreds of feet in the air.


There was some more stuff about offsetting the feedpoint in that 
handout, but nothing that remotely applied to a fractional wavelength 
vertical just sitting on the dirt with a few radials laying directly 
on the lawn.


They got rid of lossy traps and loading coils by using even lossier 
coax and some folded wires for a loading system.


This is all why, as frequency increases and the current and voltage 
moves up the antenna, the GAP on most bands isn't terribly bad.  This 
also why it is a real dog of an antenna on 160 and 80, where it is 
very short electrically, has no ground system, has an exceptionally 
poor loading method, and where it folds the radiator back and forth 
which suppresses radiation resistance.


This is why a ten foot mobile antenna can tie it or beat it on 160, 
and why it is reasonably on par with anything else on most bands above 
80 meters.


73 Tom


I got hold of a brand new voyager about 7 years ago. The first thing I 
did was throw away all that yellow coax stuffed inside the bottom half. 
The fiberglass GAP for the elevated feed point makes a nice insulator 
for a center loading coil. Then I added some top hat wires with 
dimensions per WX7G's recommendation and fed the antenna from the bottom 
as a standard ground mounted vertical with a bunch of radials.  For 80 
meters, I put a short yard arm at the top with a pulley and hung a 
wire in parallel with the aluminum radiator. For only being 45ft tall 
this antenna has worked surprisingly well. I've since lengthened it to 
56ft and added an additional parallel wire for 40 meters. I use an 
Ameritron RCS-4 remote switch at the base to select between 160 or 80/40 
(the 80 and 40 meter vertical wires are tied together). I use a 50 to 
12.5 ohms Unun on the 160 side to raise the feedpoint Z up to 50 ohms. 
With all these modifications done in haste before various contests it 
aint pretty to look at, but it does seem to hold its own against folks 
with shunt-fed towers and inverted-Ls (at least the ones who don't use 
overly active antenna tuners :-)  ).


Here are some pictures of it when I took a trip to one of the dry lake 
beds north of here:


http://www.dellroy.com/W4EF's-Ham-Radio-Page/CQ160/2006.htm

73, Mike W4EF...



___
Topband reflector - topband@contesting.com

Re: Topband: ZL9HR

[Michael Tope]

Here is what I found, Steve:

http://k3el.wordpress.com/dx/zl9hr/propagation/

2. Operating times -- It is a condition of our operating permit that we 
leave the island during the hours of darkness. This is a general 
limitation for visitors to Campbell Island, and similar conditions 
applied during the ZL9CI http://www.qsl.net/z/zl9ci/ expedition. /This 
restriction will limit our activities on the low bands./ Although 
considerable effort was made to convince the NZ DOC that an exception be 
made to accommodate LF DX communications, this was not granted. 
Exceptions may be made due to on-island conditions, e.g. if a storm 
makes it unsafe to leave the island and go to the boat, operators will 
have to stay ashore overnight and will, of course, try and work the low 
bands as much as possible.


Looks like there will be a short window for North America starting every 
day around 0840 UTC. We are getting close to the solstice, so in the 
southern hemisphere the evening twilight should be long. This could help 
depending on exactly how the authorities define darkness.


73, Mike W4EF..

On 11/25/2012 3:00 PM, wb6r...@mac.com wrote:

Re: ZL9HR on 160  80. Anyone have any insights on this?

No antennas are allowed in or near the water, and the team will have to shuttle 
back and forth from the island as no overnight stays are  allowed (unless the weather 
prevents return to the boat).

Steve WB6RSE
___
Topband reflector - topband@contesting.com




___
Topband reflector - topband@contesting.com

Re: Topband: ZL9HR

[Michael Tope]

Steve, et al:

I also found this blurb on K3EL's blog:

http://k3el.wordpress.com/

One of the conditions of our landing permit is that we are off-island 
during the hours of darkness – we will return to the boat at night. So, 
don’t expect to hear us on the air between approx. 1000-1500 UTC. 
Exceptions may be made if, for example, bad weather makes a safe return 
to the boat impossible – so if you do hear ZL9HR on at night, don’t 
assume it’s a pirate, we’re probably just stranded due to wx and happily 
taking advantage of the low band propagation.


By chance I have a copy of the 9V1YC produced ZL9CI video which I had 
never bothered to watch (I was saving it in case I ever needed it for a 
radio club meeting program). I just watched the video and they mention 
that they were restricted from being on the island from local midnight 
to 5:30 AM local which is roughly consistent with the 1000-1500 UTC 
restriction mentioned above (ZL9CI took place in January which may 
explain some of the difference). For the ZL9CI expedition, the zodiak 
trip from the boat to the docking site took just a few minutes and the 
meteorological station buildings were only a short walk from the zodiac 
docking site. These restrictions should allow for ~ 80 minutes of 
operating time from local sunset until mandatory departure. On the ZL9 
sunrise side folks in central California will have a brief shot during 
mutual twilight (wouldn't you know that Los Angeles misses mutual 
darkness by a few minutes :-( ).


73, Mike W4EF..

On 11/25/2012 5:16 PM, wb6r...@mac.com wrote:

On Nov 25, 2012, at 4:43 PM, Michael Tope wrote:

http://k3el.wordpress.com/dx/zl9hr/propagation/

2. Operating times -- It is a condition of our operating permit that we leave 
the island during the hours of darkness.
___

All: Thanks for the comments on and off list. Mike, W4EF, found the definitive 
caveats as noted above.  It's been so long since ZL9 has been QRV that I didn't 
recall the restrictions. As far as 160/80 are concerned, we can only hope they 
can stay QRV for some time after their sunset before having to leave for the 
night. And/or that the wx is just enough to keep them overnight but otherwise 
not severe.

Past operations I know of:

ZL4LR/A 1978
ZL9AMO et al 1988
ZL9DX  K8VIR/ZL9 1997
ZL9CI 1999

Good hunting all.

Steve WB6RSE
___
Topband reflector - topband@contesting.com





___
Topband reflector - topband@contesting.com

Re: Topband: PT0S

[Michael Tope]

I'll name names. Last night on 80 meters, K0MN kept calling over and 
over through the entire period (~15 minutes) when PT0S was listening for 
JAs at his sunrise. To make matters worse, somebody decided it would be 
helpful to read him the riot act on PT0S's frequency as in K0MN idiot 
over and over (NOT! helpful). What's worse is that after he quit 
listening JA only, PT0S worked K0MN (so much for Karma!). Sending A$$ 
and FU over and over when someone's tuning on the DX QRG isn't helpful 
either.


73, Mike W4EF..

On 11/12/2012 7:26 AM, Eddy Swynar wrote:

On 2012-11-12, at 10:14 AM, Les Kalmus wrote:


I heard the same thing you did Gary but I wasn't able to break the pileup on 
either band.
I hope I can eventually get through what is among the worst intentional QRM on 
a DX station that I have heard.



There really should be a way of ...outing some of these deliberate QRM 
generators...

I realize that some of the stuff is being generated anonymously, but we all know the call signs of 
one, or more, REPEAT offenders---guys who continually insist upon calling out of turn, 
guys who repeatedly send their call signs right over top of existing QSOs, guys who repeatedly call 
on the DX stations transmit frequency, etc. etc. etc. ...in short, guys who just continually refuse 
to get it.

Years ago I wrote to ARRL  suggested they publish a monthly list of DX station non-QSLers in 
QST---much like they had a column called Pre-Historic Signals in 1929 when they were actively 
pushing to get Amateurs to raise the bar in the quality of their signals---but I never received 
so much as even an acknowledgement of my idea. I guess it wasn't in keeping with being polite  
gentlemanly.

Let's face it: the situation is HARDLY improving...and wishing / hoping / praying / 
keeping our fingers crossed will not help make these louts take-up stamp collecting, 
instead of DX'ing.

What will it finally take until we collectively say, Enough is enough!...?

~73~ de Eddy VE3CUI - VE3XZ

___
Topband reflector - topband@contesting.com





___
Topband reflector - topband@contesting.com

Re: Topband: PT0S

[Michael Tope]

I should add that in fairness to K0MN, I don't know if that was actually 
him calling PT0S or someone bootlegging his call. I've seen at least one 
case (and I am sure there have been plenty of others) where the culprit 
is bootlegging the callsign of someone else. In the case I am thinking 
of, the culprit was jamming the DX qrg, not calling repeatedly out of 
turn (the latter being a more subtle way for a bootlegger to tarnish 
someone's reputation).


73, Mike W4EF...

On 11/12/2012 8:13 AM, Michael Tope wrote:
I'll name names. Last night on 80 meters, K0MN kept calling over and 
over through the entire period (~15 minutes) when PT0S was listening 
for JAs at his sunrise. To make matters worse, somebody decided it 
would be helpful to read him the riot act on PT0S's frequency as in 
K0MN idiot over and over (NOT! helpful). What's worse is that after 
he quit listening JA only, PT0S worked K0MN (so much for Karma!). 
Sending A$$ and FU over and over when someone's tuning on the DX 
QRG isn't helpful either.


73, Mike W4EF..

On 11/12/2012 7:26 AM, Eddy Swynar wrote:

On 2012-11-12, at 10:14 AM, Les Kalmus wrote:

I heard the same thing you did Gary but I wasn't able to break the 
pileup on either band.
I hope I can eventually get through what is among the worst 
intentional QRM on a DX station that I have heard.




There really should be a way of ...outing some of these deliberate 
QRM generators...


I realize that some of the stuff is being generated anonymously, but 
we all know the call signs of one, or more, REPEAT offenders---guys 
who continually insist upon calling out of turn, guys who repeatedly 
send their call signs right over top of existing QSOs, guys who 
repeatedly call on the DX stations transmit frequency, etc. etc. etc. 
...in short, guys who just continually refuse to get it.


Years ago I wrote to ARRL  suggested they publish a monthly list of 
DX station non-QSLers in QST---much like they had a column called 
Pre-Historic Signals in 1929 when they were actively pushing to get 
Amateurs to raise the bar in the quality of their signals---but I 
never received so much as even an acknowledgement of my idea. I guess 
it wasn't in keeping with being polite  gentlemanly.


Let's face it: the situation is HARDLY improving...and wishing / 
hoping / praying / keeping our fingers crossed will not help make 
these louts take-up stamp collecting, instead of DX'ing.


What will it finally take until we collectively say, Enough is 
enough!...?


~73~ de Eddy VE3CUI - VE3XZ

_



___
Topband reflector - topband@contesting.com

Re: Topband: Outing The Scofflaws...

[Michael Tope]

For illegal power, there is not much you can do unless, as you say, you 
are in the shack watching it. For bad operating you can diplomatically 
mention to the offender that your heard someone using their call and 
using very poor operating techniques (specifics supplied) and that you 
figured that they would want to know about it. This avoids the direct 
accusation by giving them the benefit of the doubt, but it does send the 
message that the observed behavior( regardless of the perpetrator) is 
totally unacceptable. I think any person with a conscience will 
eventually get the message that they need to clean up their act. For a 
person with no conscience, you can hope they find another hobby.


73, Mike W4EF

On 11/12/2012 8:48 AM, cqtestk...@aol.com wrote:

It's like the guys we know who operate illegal power. Several of them are
well known contesters, and some are well known 160 guys.  Others are packet
cheaters in contests.  No one ever confronts these guys, at least
directly...including me.
  
I was once accused of using illegal power in contests, through a third

party while I was out in KH6...untrue.  However, the guy who made the
accusation never came to me about it.
  
Unless you are in the guy's shack while he's doing whatever offense it is,

you never can know for sure if he is doing it.  Result, it's hard to get in
  the guys face about it.
  
Bill K4XS/KH7XS
  
  
  
In a message dated 11/12/2012 4:37:05 P.M. Coordinated Universal Tim,

p...@n1bug.com writes:

This  post may get moderated, but I will try it anyway.

I question how many  good operators would have the... [ahem]
courage to out the  offenders. As I say this I am thinking of
one particular individual whose  operating standards are consistently
deplorable. This was often the topic  of discussion on the DX chat
sites until the individual in question joined  the room. To my
knowledge no one has ever said one word to him about his  operating.
He was simply welcomed with open arms.

Honestly there is  so much that goes on these days it makes me wonder
if I really want to be  a DXer any more. It is all too common to see
remarks like this: I thought  I heard him send two letters of my
call so I sent a report. I will check  the online log and see if I'm
there. By my standards and what my elmer  taught me, that is not a
QSO even if he is in the log. I certainly would  not count it.

That's all I'm going to say on the subject of poor  operating.

73,
Paul  N1BUG
___
Topband reflector  - topband@contesting.com

___
Topband reflector - topband@contesting.com





___
Topband reflector - topband@contesting.com

Re: Topband: Outing The Scofflaws...

[Michael Tope]

Good advice, Mike. In fact, that's why I followed up my initial post 
with the suggestion that I had know way of knowing that the previously 
named offender was the actual perpetrator of the bad operating. In 
hindsight it would have been better to contact him privately and pass on 
my observations. Mea culpa.


73, Mike W4EF...



On 11/12/2012 9:36 AM, mstang...@comcast.net wrote:

Michael,

Good advice. Remember to contact the potential offender off-list.

Mike N2MS


- Original Message -
From: Michael Tope w...@dellroy.com
To: topband@contesting.com
Sent: Mon, 12 Nov 2012 17:27:01 - (UTC)
Subject: Re: Topband: Outing The Scofflaws...

For illegal power, there is not much you can do unless, as you say, you
are in the shack watching it. For bad operating you can diplomatically
mention to the offender that your heard someone using their call and
using very poor operating techniques (specifics supplied) and that you
figured that they would want to know about it. This avoids the direct
accusation by giving them the benefit of the doubt, but it does send the
message that the observed behavior( regardless of the perpetrator) is
totally unacceptable. I think any person with a conscience will
eventually get the message that they need to clean up their act. For a
person with no conscience, you can hope they find another hobby.

73, Mike W4EF
___
Topband reflector - topband@contesting.com





___
Topband reflector - topband@contesting.com

Re: Topband: Fw: Outing the Scofflaws - Getting Old

[Michael Tope]

I understand what you are saying, Bruce, but we should remember that 
other DXers may not be the only ones listening:


http://pt0s.com/about.html

If you read this you will see that the folks who put this expedition 
went to a lot of trouble to get permission to operate on this entity. 
Part of this involved representing Amateur Radio in a positive light:


   As a consequence of several meetings with the Brazilian
   authorities, the organizers of the Expedition, represented by the
   Araucaria Dx Group's Chairman (PY5EG Atilano de Oms), had the
   opportunity to show the relevance of ham radio activity to the
   communications community as well how the Dx-Pedition intends to
   cooperate to meet the requirements of the occupation of the
   archipelago and demonstrate its compatibility with the ongoing
   activities. The Brazilian Navy through SECIRM is giving total
   support to the expedition.

   During all contacts with the Brazilian entities, we emphasized the
   importance of the work done by radio amateurs and reciprocity that
   could derive from this understanding. The operation is aimed not
   only at bringing this rare location to the DX community, but also to
   demonstrate that Amateur Radio is in fact totally compatible with
   the scientific and environmentally sensitive nature of the St. Peter
   and St. Paul Archipelago. The Araucaria DX Group greatly appreciates
   the understanding and support of all its friends and Brazilian
   authorities.

Sure, I expect there will always be a handful of pyscho-stalker types 
who derive some weird pleasure from jamming DX stations, but when the 
behavior accomplished mainstream DXers starts become indistinguishable 
from the weirdos, we are in trouble.


73, Mike W4EF...

On 11/12/2012 1:30 PM, Bruce wrote:
This is my opinion also. The prestige of 160 comes from its degree of 
difficulty.Poor propagation, Jammers, QRM, QRN, and bad locations 
are all part of what makes it difficult. We then work to over come and 
make the contact with technology and operating practices as best we can.


73
Bruce-K1FZ



There will always be jammers, cops, tuner-uppers, and those 
that call a lot but listen little the only meaningful thing I can 
do about it is to minimize my own mistakes.

Every serious DXer I know says ignoring them is the best policy.
DXing in general (and breaking pileups in particular) is a challenge 
and these guys are part of it. Making the contact IN SPITE OF THEM 
just makes it that much sweeter.


73, Jerry K3BZ
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Re: Topband: Near Field/Far Field

[Michael Tope]

If you look at Ken Norton's paper from the December 1941 Proceedings of 
the IRE The Calculation of Ground-Wave Field Intensity Over a Finitely 
Conducting Spherical Earth, he lays out the equations for the E field 
from a vertical radiator for short distances (short enough to neglect 
earth curvature). In these equations Norton explicitly shows three 
distinct terms; a direct wave term, a ground reflected wave term, 
and a surface wave term. If you neglect the surface wave term and add 
up just the direct wave and ground reflected wave terms for the case 
of psi=0 (i.e. zero elevation angle), the sum of the terms goes to zero 
except for the case of infinite ground conductivity. In that case, the 
surface wave term goes to zero and the sum of the direct wave field and 
the ground reflected wave field is twice the direct wave field which 
accounts for the 3dB gain at the horizon that Dick mentioned in one of 
his previous posts.


The 1941 paper mentioned in the previous paragraph references another 
paper by Norton that was published in the Proceedings of the IRE in 
September 1937 - Physical Reality of Space and Surface Waves in the 
Radiation Field of Radio Antennas.  In this paper, Norton discusses 
whether or not the physical interpretation of the surface wave portion 
of the E field solution is equivalent to a Zenneck guided surface 
wave. At the end of the paper, Norton leaves the question open stating, 
Although the above evidence is illuminating the final establishment of 
Sommerfeld's view that the surface wave is similar to a guided wave on a 
wire must await further theoretical and experimental studies.


It sounds like we are asking the same questions as Norton asked in 1937 
again in 2012. One possibility that I suggested previously, which would 
reconcile the discrepancy between the 2.8 km elevation pattern with that 
of the 50 km elevation pattern, is that the surface wave portion of the 
field is truly a guided wave that propagates along earth's surface in a 
manner analogous to the way energy flows down a transmission line. Since 
real earth is lossy, you would expect that part of the field to die off 
with increasing distance eventually (due to ohmic heating rather than 
radiation into space) leaving only the field from the skywave terms in 
the field equations. I think the argument that it is valid to sample the 
elevation pattern of the vertical radiator at some modest distance (e.g. 
2.8 km) and then project that field radially on to the distant 
ionosphere, depends upon some implicit assumptions about the 
corresponding amplitude, phase, and direction of the H-fields in that 
moderate distance elevation pattern. Rules of thumb about far field 
distance aside, what ultimately matters is whether the E-field and H 
field are physically orthogonal and in-phase.


Interesting topic.

73, Mike W4EF...

On 10/12/2012 10:37 AM, Guy Olinger K2AV wrote:

On Fri, Oct 12, 2012 at 7:27 AM, Richard Fry r...@adams.net wrote:


There is little point in dissecting the far field tens of kilometers from
a vertical monopole to find the field remaining there at low elevation
angles, because that does not account for ALL of the fields radiated by the
monopole. In fact, that approach misses the existence of the greatest
contributor to low-angle radiation -- the fields of the elevation pattern
within 1 km of a 160m monopole radiator.



First, I would like to thank Richard for passing on the information from
the helicopter measurements.  It was quite non-intuitive to me, and
certainly got my attention.  Then my intuitive vast over-simplification of
the vector arithmetic was telling me that it should continue into the far
field, and there was possibly some serious missing stuff in a typical
far-field plot.

I certainly would have thought that the far field was formed with
sufficient accuracy out 2.8 km from the monopole. Experimenting with
various ground and frequency, results quite more indicated CONFORMITY
between NEC4 near field values and the helicopter measurements. This at the
time was advanced as proof of low angle energy that was MISSING in the far
field plot, that needed to be added in.

Recap:  NEC4 running NEAR field analysis ALL THE WAY OUT to 2.8 km
duplicated the helicopter measurements.  For myself as well, 2.8 km WAS all
the way out.  So why would there be a discontinuity like that with the far
field plot?  So I decided to see what the near field process is doing, very
carefully.

I started all over from scratch with my 1/4 wave over 120 buried 0.4
radials. I used that antenna so that I didn't take myself out of the gold
standard monopole + radial paradigm that has been validated over and over.
  I got a very similar result at 3 km, noting some mild modification due to
1.825, but obviously begging the same intuitive question:  Where did all
this low angle radiation go that is so clearly in the near field table at 3
km.  First look score goes to Richard.

Running near field setups 

Re: Topband: Skywaves from Monopole Surface Waves

[Michael Tope]

On 10/9/2012 7:31 AM, Tom W8JI wrote:
So again my question - if this low-angle ground-wave (aka 
surface-wave) energy dies off so quickly (e.g. down 20dB at just 20 
miles), how does any of it get to the ionosphere where it can be 
useful for topband DX?


Is the disagreement about how useful the really low angles are, or is 
the disagreement about if a low angle measurement (groundwave) is 
meaningful in determining changes in radiation at useful higher angles?


Groundwave has no value at all for working long distances, and under 
nearly all conditions extremely low angles have no value on 160 meters 
for DX.


On the other hand, I don't think many would dispute a groundwave 
measurement of FS changes between various vertically polarized 
radiators would be closely tied to FS at usable higher angles. The 
exception would be those cases where high angle horizontal propagation 
is a dominant mode.


I have about ten pages of ABC tests from here to VK/ZL and I'm pretty 
comfortable that angles at or below 20 - 30 degrees dominate almost 
all of the time, with the most common exceptions only at sunrise or 
during geomagnetic disturbances. This even compared a dipole at about 
280 feet effective height above ground, so there was lowish angle 
horizontal polarization in the test.


Groundwave is a very good way to evaluate vertical antenna efficiency, 
but certainly not a horizontally polarized mode. I know someone who 
measured a horizontal antenna at a modest distance and claimed he 
improved efficiency 10-20 dB by removing his balun and altering 
feedline length. :-)




Tom,

I agree that groundwave measurements provide a meaningful way to 
evaluate vertical efficiency, but not horizontal antenna efficiency.  
Also, I see no reason to dispute your findings on which angles of 
radiation are best for DX. I remember eavesdropping on some of those 
test you made when you were keeping daily skeds with VK3ZL and I've done 
no such tests myself.


My question (it is not a disagreement because I am not sure I know the 
correct answer) is whether the NEC-4 elevation patterns which include 
surface-wave (such as the one Richard Fry has linked to) are 
representative of what gets projected on to the distant ionosphere or if 
the far-field skywave pattern is a better representation. If Richard's 
assessment is correct, then a vertical over average soil should have as 
much gain at 1 or 2 degrees elevation angle as it does at 20 or 30 
degrees. Furthermore, it should only be a few dB down from a vertical 
over salt water over that same broad range of elevation angles. That 
certainly contradicts the conventional wisdom.


73, Mike W4EF.





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Re: Topband: Skywaves from Monopole Surface Waves

[Michael Tope]

On 10/7/2012 3:42 AM, Richard Fry wrote:



It will be seen from the data that no notch exists in the fields 
radiated by the monopole at elevation angles of 3 degrees and less, as 
expected by some when considering only the far-field patterns shown by 
MoM (NEC) software, and in antenna textbooks.


That low-angle radiation can reach the ionosphere to produce a skywave,
under the right conditions.   That skywave can be very useful to hams
using vertical monopoles, even though its existence may not be
recognized.


Everyone seems to agree that at moderately short distances from the 
vertical radiator (a few miles), there will be pattern fill-in at very 
low-angles and that this fill-in is not predicted by the far-field 
pattern equations. What everyone seems to be dancing around (Dick hints 
at it above) is whether or not any of this low-angle ground-wave energy 
ever reaches the ionosphere and if so, how? Clearly if you keep 
increasing the distance from the vertical radiator, the E-field at zero 
elevation angle drops faster than 1/r (except in the case of infinitely 
conductive ground) so eventually the notch in the pattern predicted by 
the far-field equations appears.  One can image taking the helicopter 
used by Dick's BC engineer friend and repeating E-field versus height 
measurements at increasing distance intervals out to many miles. In 
fact, one of the NEC-4 surface-wave plots Dick posted a few days ago 
shows that for average soil a fairly deep low-angle notch (~ 20dB) has 
already appeared in the elevation pattern at just 20 miles distance from 
the vertical radiator:


http://i62.photobucket.com/albums/h85/rfry-100/Surface_Wave_Flds.jpg

So again my question - if this low-angle ground-wave (aka surface-wave) 
energy dies off so quickly (e.g. down 20dB at just 20 miles), how does 
any of it get to the ionosphere where it can be useful for topband DX?


73, Mike W4EF..


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Re: Topband: Skywaves from Monopole Surface Waves

[Michael Tope]

I have long had a suspicion that some fraction of the power in surface 
wave must be converted to skywave as the surface wave encounters 
discontinuities in the ground medium (both physical geometry and 
dielectric parameters). Some folks I know from work were doing research 
on low-loss dielectric waveguides for microwave and millimeter waves 
(somewhat analogous to an optical fiber for RF). The degree to which 
these dielectric waveguides won't radiate despite not having a 
conductive outer shield is a function of how smooth the bends are and 
the degree to which discontinuities are minimized.


Another way to look at this is to ask the question - how would a 
vertical perform if it were installed on a perfectly uniform ground of 
average conductivity that conformed to the ideal geoid as compared with 
a more realistic installation - hills, mountains, lakes, and other 
abrupt changes in characteristics of the surface wave medium? In the 
former case, would the surface wave contribute less or more to the 
skywave power at low angles than in the latter case?


73, Mike W4EF..

On 10/3/2012 9:05 AM, Richard Fry wrote:
The elevation patterns of vertical monopoles over real earth has been 
discussed in recent threads here 
(http://lists.contesting.com/archives//html/Topband/2012-10/msg00140.html). 
The common belief based on NEC far-field elevation patterns for those 
conditions shows little relative field at low vertical angles, and 
zero field in the horizontal plane.  However the surface wave must be 
included in a complete analysis of monopole performance, because it 
contributes substantial low-angle radiation that will reach the 
ionosphere to generate skywave service under the right conditions.


Below on this topic is part of an e-mail exchange of a few months ago 
between Gerald Burke of Lawrence-Livermore National Laboratory and me, 
and is quoted with his written permission.  As many will recognize, 
Mr. Burke is co-author of the software engines used in NEC computer 
programs.


This text applies to NEC surface wave plots attached to my e-mail to him.


Hello Mr. Burke -



Would you expect the fields at elevation angles of 1 to 10 degrees
in these plots to continue on to the ionosphere, and under the right
conditions be reflected back to the earth as skywaves?



R. Fry


The low angle 1/R fields should reach the ionosphere, although 
perhaps not
accurately predicted by NEC, since it does not include the effects of 
earth

curvature and the ionosphere.

Regards,
Jerry Burke
LLNL 


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Re: Topband: Proper Decorum On The Gentleman's Band...

[Michael Tope]

On 2/9/2012 6:48 AM, Roger D Johnson wrote:
 The Gentleman's Band has been dead a long time, Eddy. It's now inhabited by
 the same
 type of operators that infest all the other bands.

 As for QRL? It's often used by lids on the DX's frequency to cause QRM and 
 provoke a
 response. A version of sending someone's call on the DX transmitting 
 frequency thus
 provoking a slew of ups, lid, a**hole, etc.

 Best just to ignore it and get on with your life.

 73, Roger

Yes, the response to bad behavior seems to be more bad behavior. 
Sometimes the response to QRM is 10x as bad as the QRM. Sometimes a 
polite and directed response can be constructive (as in EF up if I'm 
on the wrong VFO or QRL if someone tunes up on a DX station's QRG 
accidently). Send FU or A$$ is never helpful and once any 
interference has revealed itself to be deliberate the absolute best 
response is NOTHING.  Keep a Shmoo in your shack so you have something 
to punch or club, if necessary.

73, Mike W4EF..


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UR RST IS ... ... ..9 QSB QSB - hw? BK

Re: Topband: 160 metre vertical with 'top loading'

[Michael Tope]

On 4/26/2011 1:49 AM, Tom Boucher wrote:
 I take your point Yuri, but my simplistic way of looking at the current 
 decreasing along a straight quarter wave of wire is due to the current flow 
 through it's distributed capacitance to ground. Maybe that is wrong and I 
 should go back and look at my transmission line theory.
A matched low-loss transmission line has distributed capacitance to 
ground (i.e. x number of pf/foot), but yet it does not have an 
appreciable current taper. Only when you introduce an open circuit at 
the end does the large current taper appear (i.e. the standing wave). 
Similarly it's the open circuit at the tip of the radiator that forces 
the current taper. In fact if you imagine a two-wire transmission line 
where the wires start out parallel and then are slowly spread apart at 
an ever increasing included angle, you'll see that at first you have (at 
very small included angles) an impedance transformer (step up to higher 
Zo), then as you get to larger included angles (i.e. ~90deg) you have 
the equivalent of an inverted-v dipole (well not really inverted unless 
you imagine the feedline coming downward toward the ground, but you get 
the idea). At an included angle of 180degrees you have a flat-top 
dipole.  Thus, there is a continuum between the transmission line 
paradigm and the antenna paradigm, which can be helpful when trying to 
abstract what goes on the antenna element, but you have to be careful 
how far you push the transmission line analogy.

 Surely the fact that it is an electrical quarter wave is due to the straight 
 wire being part of one very large coil turn and therefore having an 
 inductance, combined with that distributed capacitance causing resonance at 
 one particular frequency? If that is so, then isn't my theory of the current 
 decay being due to flow through distributed capacitance along it's length 
 still correct?
Consider that the inductance of the wire is also distributed between 
those infinitesimal capacitors to ground. This is analogous much more to 
a transmission line than a lumped element resonant circuit. The ratio of 
the distributed L to distributed C does change along the length of the 
wire (i.e. the characteristic Zo of this putative transmission line is 
not constant), but is still more like a transmission line than a lumped 
circuit. Of course, as I said before you have to be careful how far you 
push the transmission line analogy. It is, after all, an antenna :-)

 AA7JV said that the argument against current at both ends of the loading coil 
 being the same, is that you cannot have high current and high voltage at the 
 top of the coil because that represents much higher power than you are 
 sticking into the base of the antenna. That's not true because we are talking 
 about VA not Watts, i.e. there is a phase difference between V and I.
Yes, in fact if you use the resonant series LC circuit analogy, as you 
move from source voltage Vs toward the load, the voltage rises across 
the series inductor in proportion to I * XL and then tapers back down 
across the series capacitor in proportion to I * XC until you reach the 
load where the voltage is I*RL which is equal to the source voltage Vs. 
There is no current taper in this circuit. The peak voltage occurs at 
the common node between the inductor and capacitor and is Vs +jI*XL. 
That is the voltage step-up that George was referring to. It does not 
necessitate a current taper because of the 90 deg phase shift between 
the inductor voltage and the current through it.

73, Mike W4EF

 73
 Tom G3OLB




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UR RST IS ... ... ..9 QSB QSB - hw? BK

Re: Topband: LINEAR vs TOP LOADING

[Michael Tope]

On 4/23/2011 5:30 PM, ZR wrote:
 On 4/23/2011 7:04 AM, ZR wrote:
 The linear loaded KLM 40 and 80M yagis never lived up to their hype. OTOH
 the little Cushcraft 2el 40 with loading coils plus a capacity hat way
 out
 on the elements is a proven winner.

 Ive sold one of my 40M 4el KLM's and made a pair of CC style 2el from the
 other.

 Carl
 KM1H
 Some KLM Yagi owners have changed to high Q loading coils made by W6ANR
 and have been happy with the results.

 Rick N6RK
 Thats interesting Rick.

 One of the CC engineers wrote in QEX that high Q coils was not desired on
 their 40M. I dont remember exact details but it should be available thru the
 ARRL archives. The author was Rick Littlefield, K1BQT.

 Carl
 KM1H
Perhaps the reason was mechanical. At some point depending on the 
current distribution, an additional improvement in unloaded Q of the 
loading coil will provide diminishing returns in terms of efficiency. 
Higher Q inductors are generally bigger than there lower Q counterparts 
(up to a point anyway) which implies more cross-section for the wind to 
catch. The big W6ANR inductors probably pay bigger efficiency dividends 
on shortened 80 meter Yagis where the radiation resistance is lower, 
than they would on a 46 ft long CC 40 meter element.

Mike W4EF...

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UR RST IS ... ... ..9 QSB QSB - hw? BK