What I found interesting in the HEBA103 document was that it seemed the
FS measurements were taken at ground level along two compass points. If
I'm not mistaken, the power radiated is spread out over a 3-dimensional
space and from that standpoint, I don't see how improved FS measurements
I think there are a couple of reasons I want to try this method.
First is that it's a technically cool use of a VNA - which is my
personal favorite gadget in general.
I live in an area surrounded by farm lands and assume that the soil here
is nice and conductive. But I have no idea what
There is another practical issue here. I would agree that elevated
radials can work great. But in practice, MAINTENANCE of the elevated
radials is a non-ending headache. Around here we have deer and ice and
wind and on and on. I ran various 40m 4SQ elevated radial schemes for
years and
Saw the interview. Fascinating. The guys have done a ton of work and
that approach makes sense for these environmentally hyper-sensitive QTH.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 5/25/2023 9:57 PM, j...@kk9a.com wrote:
Tim Duffy's AA7JV R.I.B. interview is on Youtube:
The RIB is an interesting concept.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 5/24/2023 4:05 PM, Jim Brown wrote:
On 5/24/2023 11:10 AM, Charles Morrison wrote:
Where can we find George's work for these items ??
Just looked at his AA7JV qrz page, where there's extensive
Grant, that higher Rr is the path I took as well.
My 160m antenna is a bit longer than 1/4wl - trimmed in length so that
the resistivity component of Z was 50 ohms. It's got Xl of course, so I
use a series C bread slicer at the tower base to to cancel the Xl.
My thought back then was that
The casual antenna nut considering a parasitic vertical array will need
to pay very close attention to the comment on having a VERY SERIOUS
ground radial system on all elements.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 3/24/22 11:55 AM, Stan Stockton wrote:
Different people
The secret to using this sort of solution is to apply just enough of it
to kill off the mixing products that are the result. The good news is
that you get (generally speaking) a 3:1 payback - so 1 db attenuation of
the BC station will knock the mixing product down by 3 dB. So 45 dB (as
the
Worked him this weekend from KS first night. 5:17Z. Only DX seen in my
whopping 2 hours of activity.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 2/1/22 12:03 PM, w3...@roadrunner.com wrote:
Jim, I said the same thing in the ARRL 160 contest. I heard DPM loud
and clear and
Not sure about the other KS stations. But here in NW KS, if I don't
spin the HiZ RX circle 8 around to point to SW, I just won't hear AZ
unless the station calling is really strong or the prop is peaking or
something - enough signal so it's detectable over the other callers,
strong to the
On N6LF web page you can find the QEX series on ground mounted radials.
And there is a ton of discussion of this topic on the reflector as it
seems to come up often (may be mixing it with the towertalk reflector).
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 1/1/21 11:28 PM, List
N6LF Rudy's web site and associated QEX series has empirical data to
answer all of these questions regarding the number and length of on
ground radials.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 12/10/20 11:14 AM, Mark - N5OT wrote:
Yeah. I don't claim to be a radial expert
I have a DLEX357OV front loading LG here. About 3 years old? It's quit
as far as I know although my antennas are about 250' from the house, and
I put 3 big clamp-on type 31 ferrites at the cable exit from the dryer
just as a token preventative.
73/jeff/ac0c
alpha-charlie-zero-charlie
for a 500 kw VLF system caused
severe television interference to neighbors that forced premature site closure.
73
Frank
W3LPL
- Original Message -
From: "Jeff Blaine"
To: topband@contesting.com
Sent: Saturday, November 7, 2020 5:43:25 AM
Subject: Re: Topband: OT - Bondi
I of course defer to Frank's expertise here. But after thinking about
this for a couple of hours, I'm trying to wrap my head around this arc
risk concept as well. It's interesting and I toss this comment out
because my two sets of 4sq don't have a single cross-bonded wire
anywhere - all the
Had the same issue as you Lloyd here - in a prior antenna matching net.
On 160 it would start to drift after calling CQ a few times. I did not
flip to vac caps. But instead ended up using lower valued, paralleled
doorknobs, so that the current was shared among multiple paralleled caps
and
I don't know about the price end of it. But Jim's comment about the
alignment is true.
I fiddled around with some designs and then K8ZOA managed to talk me
into back into the land of sanity. Jack cooked up a version of his
filter which put one of the notches on the head of our local BC
Great job Lee
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 4/8/20 4:11 PM, Lee STRAHAN wrote:
Robin WA6CDR mentioned this to me in an earlier exchange this AM. It was not
me. Should have mentioned that before. Sorry Robin, You the Man!
Lee K7TJR
-Original Message-
From:
When it comes to elevated radials, the amount of guys who have strong
opinions on the subject are many - and unfortunately the amount of
objective data behind those strong opinions is generally not existent.
On the other hand, the N6LF work is one of the few well documented
objective works
I need to add a spark gap of some sort onto my full-size 160m
insulated-base tower. Looking for ideas.
Making the spark gap is simple. What has me asking for ideas is the
weather element - we have a lot of snow, ice, rain here and a spark gap
needs to keep that stuff off. But put a little
I have a full size vertical built from 25G running against about 80 1/4
WL radials - #18 insulated wire sewn into the ground an inch or two
below ground. There is a single ground rod next to the base but no
other ground rods on this tower.
We had a lot of lightning here last week and the
An inverted L without radials is a random length wire and the
measurements are of no meaning until there is a ground system to make up
the other half of the antenna.
But to Wes point, the 259 and big 160m antennas is a recipe for going
nuts. You don't even need a high powered BC station -
This makes complete sense to me. You are right - FTx is a different
beastie and compared with RTTY, the latter takes a ton more HUMAN work
to bag the week ones.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 8/2/19 7:06 PM, GEORGE WALLNER wrote:
Nobody is talking about "shutting"
Around here, lightning arrestors on these power cables are the prime
candidate. I have exactly the same issue here and every couple years
have to go track down one that has started making racket over the summer
storm season. The noise is in-band and you can't filter it generally
speaking.
I used a W1W relay at the top of mine for years without incident.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 4/16/19 7:22 PM, Jim Miller wrote:
Thanks all for your help on this. It sounds like my 15Kv relay at 53ft on
the 68ft vertical is safe. It's never hot switched and provides
Is this an intellectual exercise or Jim do you want to do something at
the top of this vert - like hang a vac relay there to engage some 160m
top hat cap loading wires?
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 4/16/19 6:52 PM, HP wrote:
Just for grins - did a EZNEC free space
Brad what bearing were you pointing too?
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 15-Feb-19 3:41 PM, Brad Denison wrote:
I'll have to second VE9AA - signals in to southern NH on the 8 element
array and beverage were phenomenal. At one point I was questioning whether
or not I
Got tired of the maintenance. It was about 3-5' and was a pain in the
neck for mowing. Plus keeping tension on the lines etc was a hassle.
With a 4sq, you pay in the end. If it's elevated radials, then you pay
over time. If it's in-ground, you pay up front with the radial field
install
The last version of my elevated 40m 4-square (~2016-7?) was built with
belden stuff that had the black coating all along the length. I buffed
it up and used crimp connectors. Worked great.
My reasoning was that while the contamination was going to affect some
of the cross connects of the
Tim, My take on the popularity is explained this way. FT8 has an SNR
advantage over CW of around 5 dB, PSK31 - about 10 dB and SSB of more
than 15 dB. So for a given set of link conditions, FT8 result in a Q in
the log more often than the other modes.
Add in the poor prop conditions and
Disconnect the other antenna. Let it float.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 23-Jan-19 6:02 PM, Todd Goins wrote:
Okay, after many requests, on and off list, I disconnected the 43' T 160m
antenna at its feed point and for good measure I disconnected the coax
feedline
I worked 160m for a few years when living in a townhome. The antenna
was a trap loaded attic mounted dipole that ran through holes in the
ceiling and down the walls to the ground. Had a lot of 160m contest fun
with that. Worked all the devices in the house as well until I was able
to get
Todd, get on the contest and rock and roll. I don't know of anyone on
160m who has not given their antennas an iterative workout over time.
Bet you will do just fine. RX is the tougher nut anyway. Good luck
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 21-Jan-19 7:47 PM, Jamie
He was easy to work on 160m. Excellent OP.
But I've worked him now twice on 80m but the Q has not showed up either
time. Not sure if there is an 80m log problem, an eager SLIM or just a
couple of busted calls despite clear copy of my call both times on the
reply. If it's a slim, they were
At this location, the VNWA is a bit squirly near the BC band but with a
single L/C notch added at the device input (within the cal plane), it
works fine.
The AA-55 Zoom I have is immune and is the my go-to instrument for field
work. Recommended.
MFJ-259 is too easily disturbed and is not
Unless you have no BC stations for 200 miles distant, making
measurements with an MFJ259 on 160m is going to give you unreliable
readings. The overload threshold on that band is extreemly low.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 18-Aug-18 6:10 PM, Gary Smith wrote:
The MFJ259 is a fine box but when you get to 80m with anything near a BC
it's going to be problems. In fact I discovered the hard way that even
up on 20m the box can read funky if your antenna is big enough or high
enough. I have a Rig Expert now as well and really love that thing -
plus
Vac relay works great. Ran one just like that for several years.
Be sure to use serious bypass/choke at the relay and then at the base
for common mode on the line as the pickup will be huge.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 18-Apr-18 8:21 AM, Jim Miller wrote:
Rather
There is good and bad with the FT8.
The good is that it is bringing guys into the HF DX realm who never got
active in DX because for whatever reason they felt they did not have a
good DX station. The bad is that the focus on RTTY (my favorite mode)
has become less especially for DXpeditions
nificantly influence is
wasted time - and the clock is ticking for all of us.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 18-Jan-18 7:46 PM, Dave Heil wrote:
So this is sort of like Olympic doping or other amateur endeavors
where they keep score?
Dave Heil K8MN
On 18-Jan-18 05:38, Jeff
There is no real point of worrying about what the other guy is using.
We only can control our personal operation, and really have to leave the
other end of the Q to manage theirs.
73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com
On 18-Jan-18 1:24 PM, W0MU Mike Fatchett wrote:
They are so
Hi gary,
I thought that was the rule. But I've not dug into it because I don't
use the remotes. So just now I looked and you are 100% right. Here's
what the ARRL web page says from Section 1...
*9. Station Location and Boundary:*
*a)*All stations used to make contacts for a specific
There is no way to supervise this behavior globally. It's ultimately up
to each op to decide on what falls under ethical conduct. And opinions
vary as to what is proper and what's not, even among peoples of a single
country with similar cultural view.
I personally don't use receivers or
Question regarding the OSL cal function on the unit.
Let's say you do an OSL cal with a length of coax attached just as you
would with a generic VNA. For how long is that specific OSL CAL applied?
I mean, does it persist until it's deleted, or until you change
frequency away from the range
Their meaning with respect to gain as unimportant is due to the fact that
the RX antenna is all about SNR maximization. A low noise preamp can fix
overall signal weakness, if your rig's preamps are insufficient.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
There is some data on this page:
http://www.w0qe.com/Technical_Topics/small_signal_relays_at_rf.html
I have used the RTD140xx series Schrack/Tyco for years in primarily RTTY
contesting duty at the KW power level - all without fail. But I have not
conducted BDV testing on those relays.
The Hi-Z buffers have a feedpoint Z around 50K ohms. So a single 4' ground
rod provides an adequate round system. No radials needed.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
From: James Rodenkirch
Sent: Tuesday, February 11, 2014 3:20 PM
To: Top Band
’ away from anything).
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
From: James Rodenkirch
Sent: Tuesday, February 11, 2014 7:55 PM
To: Jeff Blaine ; Top Band Contesting
Subject: RE: Topband: Hi-Z Antennas Two Element Array Systems 2-LV2-5
Tnx, Jeff
From: j...@ac0c.com
S9 in KS @ 2:20 UTC
S/SE on HiZ pro 4-8
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
From: Rick Stealey
Sent: Saturday, November 02, 2013 9:12 PM
To: topband@contesting.com
Subject: Re: Topband: Steady Carrier on 80 CW
Everyone is measuring the 3501.6
A buddy of mine has a 100’ 25G tower and wants to run it on both 160/80. I’m
thinking a par of shunts will work for that?
If you have done this, I would be interested in your comments on the general
implementation.
Thanks!
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
What affect is there of vertical *resistance* variations are the common
4-square boxes?
N6LF’s QEX article shows quantitatively the performance hit associated with
using non-resonant elevated radials. Which is interesting because non-resonant
radial lengths reduce the sensitivity of
Well said, Bill.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
From: cqtestk...@aol.com
Sent: Monday, August 05, 2013 10:03 AM
To: topband@contesting.com
Subject: Re: Topband: Blame it on global warming
Please
If I want a discussion on global
Right, the discone is sort of the LPDA of the vertical world.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
From: Charlie Cunningham
Sent: Sunday, July 28, 2013 10:34 AM
To: 'Rick Stealey' ; topband@contesting.com
Subject: Re: Topband: Height of antenna and
Tom,
Why? The same reason guys put up quads. They LOOK very cool! Imagine
standing on one end of the rhombic and saying well, you can't see the end
of the antenna without the binoculars - but it's out that-way somewhere.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original
where you need
it.
73, Mike
www.w0btu.com
On Fri, Jul 26, 2013 at 12:33 PM, Jeff Blaine j...@ac0c.com wrote:
Why? The same reason guys put up quads. They LOOK very cool! Imagine
standing on one end of the rhombic and saying well, you can't see the end
of the antenna without the binoculars
Jeff Blaine wrote:
What is the preferred method of
tuning elevated radials for uniformity?
[snip] ...
There are two methods that I thought of. Measuring the
current at the base of the vertical/radial union and
trimming lengths iteratively trying to get a uniform current
reading on all elements
What is the preferred method of tuning elevated radials for uniformity?
I realize you can measure the lengths, try to get uniform heights, etc so that
you match the model as close as possible. However, it seems that this is good
only to the first approximation.
There are two methods that I
Depends on the method used to provide the conductivity. If it's carbon
black filled, the shrinking is goin g to push the molecules of the carbon
black closer together and that results in a net decrease in volume
resistivity. It may not matter however, as carbon filled stuff is going to
be in
Some of the applications on the CD have 16-bit wrappers - meaning they won't
run under Win7x64. If you have Win7x32, it is fine. So it depends on which
flavor of Win7 you have.
The alternative for x64 is to use the XP-MODE virtual machine capability
built into the pro versions of Win7.
As Brad suggests, the article by N6LF in QEX debunks a ton of traditional
lore. Especially regarding height above ground and length.
That article seems THE place to start for anyone considering an elevated
vertical build now.
It should be noted that the QEX article is all about a single
I have the same issues here. And the similar observation - filtering before
the preamp of some kind is needed.
Regarding Steve's solution below, an alternative is available from K8ZOA
Jack Smith. 9th order elliptical with pricing is about half the Array
offering.
I am considering installing one of these hi-z or DXE buffered-type receiving
4-square arrays for 160/80. The best place on the property is on the north
west corner - in a location about 400’ from the transmit vertical. It’s got a
clear shot NE to EU and is about 600’ from the nearest house.
5:39 PM
To: Joel Harrison ; Jeff Blaine
Cc: topband@contesting.com
Subject: Re: Topband: rx array proximity to barbed wire fence
While one might claim some theoretical
interaction I have not documented any or identified any performance
degradation as a result.
I see Big Gun Mike, W5UC, has a lot
I’m cooking up my first 4-square using a set of elevated radials.
Is there a consensus on what the optimal way of laying out the radial pattern
is?
If the radials are spread out on the 0/90/180/270 points, we have overlap
between each of the radial center points (the 180 degree radial on the
Gentlemen, thanks for the offline comments.
And yes, I do understand and agree that more radials leads to less
individual radial dependence. NL's QEX articles show that in the graphs
which is very interesting. And also that a ground mounted screen is less
sensitive yet.
The current
The fundamental problem with this 2wire box (and the uVerse system and
similar types) is that it uses the entire low HF spectrum for transmission.
The system is - by design - a receiver across the 160, 80 and 40m ham bands.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original
Would not each one remain 100 ohms?
If the analysis is correct, they are in parallel and that does not add
linearly based on the individual wire values as would a series connection.
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original Message-
From: Charles Moizeau
Sent:
Phase noise is generated by the rig's LO and exists as a more broad band low
level signal. Issue is more significant with modern day DDS than with older
analog-type VFO sources. Guys who operate field day can relate...
73/jeff/ac0c
www.ac0c.com
alpha-charlie-zero-charlie
-Original
On 2011-12-31 06:30 p.m., Jeff Blaine wrote:
Phase noise is generated by the rig's LO and exists as a more broad band
low
level signal. Issue is more significant with modern day DDS than with
older
analog-type VFO sources. Guys who operate field day can relate...
73/jeff/ac0c
www.ac0c.com
Cebik was one of the antenna greats. Co author of the ARRL antenna handbook
for some time. And a lot of his work is preserved with
free access (you need to create a login though) on the cebik.com web site.
If you are serious about antennas, this is a great site.
73, Jeff ACØC
www.ac0c.com
Brian,
Look higher up in the bands (more true on the higher HF bands) - generally the
speeds are lower there.
73, Jeff ACØC
www.ac0c.com
-Original Message-
From: Craig Clark
Sent: Wednesday, November 23, 2011 10:27 AM
To: topband@contesting.com
Subject: Topband: slow speed contester
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