Re: Topband: RFI on TB

[W7RH]

Regarding RX antennas. Rather than have separate RX antennas I went with 
low noise location. Thus, TX antenna is used both RX and TX 100% of the 
time.


Obviously this is not possible for many but it can be done.

73

Bob, W7RH

--
W7RH DM35os

"It has become appallingly obvious that our technology has exceeded our 
humanity." - Albert Einstein

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Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[CUTTER DAVID via Topband]

Thanks, Guy for clarifying the re-radiation issue. I had thoughts of the other 
way around as well, ie, the inverted L (or other tuned antenna) affecting the 
rx antennas. Breaking the dual band L somewhere to negate this effect might be 
more important. To that end I thought of simply switching from 160 to 80 during 
receive on 160 and from 80 to 160 when on 80.  Does that make sense and is it a 
sensible way to do it without using additional relays?  
David G3UNA/G6CP
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Re: Topband: RFI on TB

[Richard (Rick) Karlquist]

On 7/25/2019 11:55 AM, Brian Campbell wrote:

You can put me in that group as well. Here are just two recent examples.

I'm with you both, never rule out your vertical!

During one ARRL 160 contest a few years ago, conditions were such that I
used my inverted-L over 90% of the time *even though I had two 580'
switchable-direction Beverages*. Signals at my central USA location were
coming in from all directions.

73, Mike
www.w0btu.com


In recent ARRL 160 contests I used my TX vertical on RX for all QSO's
and came in first place, high power, in the Pacific Division.
Must not be too bad.  Worked boatloads of JA's.

I kept trying RX antennas and none of them beat the vertical
in A/B tests.  I really wanted them to.

Rick N6RK
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Re: Topband: RFI on TB

[Brian Campbell]

You can put me in that group as well. Here are just two recent examples.

VE3MGY 2018 ARRL 160 -1001 QSOs - QSOs Received on TX antenna alone - 996 (99.5 
%)

VE3MGY 2019 CQ160CW - 938 QSOs - QSOs Received on TX antenna alone - 930 (99.1%)

I usually run diversity in which case I will have a couple of beverages,  
Inverted V, or loop in one ear to choose from and the Inverted L in the other 
ear but if it's relatively quiet on the L ( S1-S2 ) I will just stay there at 
times. I needed RX antennas more at the previous two QTHs but here not so much 
( at least not yet... ) In any case every QTH is different so YMMV...

73,
Brian
VE3MGY


From: Topband  on behalf of Mike Waters 

Sent: July 25, 2019 2:16 PM
To: g...@ka1j.com 
Cc: topband 
Subject: Re: Topband: RFI on TB

I'm with you both, never rule out your vertical!

During one ARRL 160 contest a few years ago, conditions were such that I
used my inverted-L over 90% of the time *even though I had two 580'
switchable-direction Beverages*. Signals at my central USA location were
coming in from all directions.

73, Mike
www.w0btu.com<http://www.w0btu.com>

On Thu, Jul 25, 2019 at 12:13 PM Gary Smith  wrote:

> I agree with Ed, never rule it out. Me, I
> tried beverages over my available space
> (Salt marsh with phragmites everywhere)
> and they were more than worthless in this
> specific location. I think between the
> proximity to salt water and the dry leaves
> making static, the beverages were much
> louder than my L.
>
> I tried several Rx options and the 3
> element HI-Z triangular was my first
> genuine success for low band Rx. Loved
> them so much I bought an 8 element and now
> use the 8 & 3 for diversity with the K3s.
> Best choice I made.
>
> There are times though when I listen to
> the transmit antenna and hear a specific
> signal the best. Very rare, but it
> happens.
>
> Just my 2 pence.
>
> 73, Gary KA1J
>
> > I use beverage "almost" all the time for receive on 160M.  However,
> > there are times, clearly a minority, when listening on my phased array
> > of 2 verticals is better.  When conditions are super quiet in the
> > winter and signals are weak from a very distant station.  Don't rule
> > out your Transmit antenna all the time.
> >
> > 73
> > Ed  N1UR
>
>
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Re: Topband: RFI on TB

[Mike Waters]

I'm with you both, never rule out your vertical!

During one ARRL 160 contest a few years ago, conditions were such that I
used my inverted-L over 90% of the time *even though I had two 580'
switchable-direction Beverages*. Signals at my central USA location were
coming in from all directions.

73, Mike
www.w0btu.com

On Thu, Jul 25, 2019 at 12:13 PM Gary Smith  wrote:

> I agree with Ed, never rule it out. Me, I
> tried beverages over my available space
> (Salt marsh with phragmites everywhere)
> and they were more than worthless in this
> specific location. I think between the
> proximity to salt water and the dry leaves
> making static, the beverages were much
> louder than my L.
>
> I tried several Rx options and the 3
> element HI-Z triangular was my first
> genuine success for low band Rx. Loved
> them so much I bought an 8 element and now
> use the 8 & 3 for diversity with the K3s.
> Best choice I made.
>
> There are times though when I listen to
> the transmit antenna and hear a specific
> signal the best. Very rare, but it
> happens.
>
> Just my 2 pence.
>
> 73, Gary KA1J
>
> > I use beverage "almost" all the time for receive on 160M.  However,
> > there are times, clearly a minority, when listening on my phased array
> > of 2 verticals is better.  When conditions are super quiet in the
> > winter and signals are weak from a very distant station.  Don't rule
> > out your Transmit antenna all the time.
> >
> > 73
> > Ed  N1UR
>
>
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Gary Smith]

I agree with Ed, never rule it out. Me, I 
tried beverages over my available space 
(Salt marsh with phragmites everywhere) 
and they were more than worthless in this 
specific location. I think between the 
proximity to salt water and the dry leaves 
making static, the beverages were much 
louder than my L.

I tried several Rx options and the 3 
element HI-Z triangular was my first 
genuine success for low band Rx. Loved 
them so much I bought an 8 element and now 
use the 8 & 3 for diversity with the K3s. 
Best choice I made. 

There are times though when I listen to 
the transmit antenna and hear a specific 
signal the best. Very rare, but it 
happens.

Just my 2 pence.

73,

Gary
KA1J
  
> I use beverage "almost" all the time for receive on 160M.  However,
> there are times, clearly a minority, when listening on my phased array
> of 2 verticals is better.  When conditions are super quiet in the
> winter and signals are weak from a very distant station.  Don't rule
> out your Transmit antenna all the time.
> 
> 
> 
> 73
> 
> 
> 
> Ed  N1UR
> 
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
> 



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Re: Topband: RFI on TB

[Ed Sawyer]

I use beverage "almost" all the time for receive on 160M.  However, there
are times, clearly a minority, when listening on my phased array of 2
verticals is better.  When conditions are super quiet in the winter and
signals are weak from a very distant station.  Don't rule out your Transmit
antenna all the time.

 

73

 

Ed  N1UR

_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[FZ Bruce]

I am using it on a base insulated vertical antenna. the relay closes
to connect it on transmit.An L would be the same. The L antenna would
float while listening You need to know your transceiver well and
program it to close the relay before transmitting. Hot switching is
destructive.If in doubt ask your other local DXers.
73
Bruce K1FZ

-From: "WW3S" 
To: "FZ Bruce"
Cc: "Mark K3MSB", "Rob Atkinson", "CUTTER DAVID", "TopBand List", "Guy
Olinger K2AV"
Sent: Thursday July 25 2019 12:15:35PM
Subject: Re: Topband: RFI on TB

How are you using this on the L ? NO on receive, then apply voltage to
close it on TX ? When open , does the L float or go to ground?

 Sent from my iPad

 > On Jul 25, 2019, at 8:36 AM, FZ Bruce  wrote:
 > 
 > Mark
 > Although I am using the RF Parts relay on transmit verticals they
work
 > great. They are 12 volt DC coils and are marked so on the relay. I
 > test checked mine with a little 9 volt battery and pulls great.In
the
 > advertisement blog it says " Rated coil voltage VDC: 26.5 " This is
an
 > advertising error. 
 > 
 > https://www.rfparts.com/vhc3-12v.html [1] [1]
 > 
 > 73Bruce-k1fz
 > 
 > -From: "Mark K3MSB" 
 > To: "CUTTER DAVID"
 > Cc: "Rob Atkinson", "TopBand List", "Guy Olinger K2AV"
 > Sent: Thursday July 25 2019 7:59:32AM
 > Subject: Re: Topband: RFI on TB
 > 
 > I’d be interested in hear about this also. I’ve always used
ground
 > radials for my INV-L but this year I’d like to try an FCP.
 > 
 > I’ve read that the INV-L as well as the FCP need to be floated
 > during
 > receive, which means two relays at the INV-L.
 > 
 > 73 Mark K3MSB
 > 
 > On Thu, Jul 25, 2019, 4:11 AM CUTTER DAVID via Topband <
 > topband@contesting.com> wrote:
 > 
 >> Guy
 >> Slightly OT, but how do you deal with re-radiation from your
 > inverted L?
 >> I'm about to erect one of your inverted L on FCP and my rx loops
 > are about
 >> 50m away in the other corner of the field. Is that far enough?
 >> David G3UNA/G6CP
 >> 
 >>> On 24 July 2019 at 07:13 Guy Olinger K2AV wrote:
 >>> 
 >>> 
 >>> I gotta agree with Rob. An inverted L aerial wire will hear ALL
 > the noise
 >>> that is around. Mine sure does. RX antenna will help enormously
 > if there
 >> is
 >>> a place to put one that does not get the noise second hand off
 > the L. Not
 >>> enough room? A bit complicated, but "repeated" noise off the L
 > can be
 >> dealt
 >>> with.
 >>> 
 >>> The worst noises around here heard on my L were all repaired by
 > the power
 >>> company. The nastiest noise was very hard to find, I actually
 > never
 >> "found"
 >>> it by looking for it. Noise turned out to be from a bad splice in
 > an
 >>> underground 13 kV cable going from the 13 kV delta overhead out
 > on US 64
 >> to
 >>> the transformer for my eastern neighbor and next house over. It
 > would
 >> come
 >>> and go with extended cold weather, but never would correlate to
 > sunlight
 >> or
 >>> darkness. I would hear it next to my transformer walking around
 > with my
 >>> battery K2 and a rubber ducky. It would never locate to up on a
 > pole
 >> (only
 >>> power noise that didn't).
 >>> 
 >>> Finally the splice hard-arced, exploding the fuse up on the pole
 > for the
 >>> neighbor's 13 kV feed, and taking those two houses off the grid.
 > The
 >> noise
 >>> went away with the cannon shot noise. Blessed quiet on 160 and
 > 80. I had
 >>> put up with that for almost four years.
 >>> 
 >>> In the end, Duke Energy completely reran his AND my buried 13kV
 > lines,
 >> and
 >>> replaced his transformer. 35 years in the ground, 35 year old
 > cable
 >> design
 >>> and materials, and deficient in THEIR opinion. Was really fun to
 > watch
 >> them
 >>> use this super-neat burrowing setup that went right UNDER the
 > woods and
 >> the
 >>> creek (whole other story). Now I can hear the lesser noises on my
 > L from
 >>> all over Apex and Cary :>) Need RX antenna for sure. That way I
 > don't
 >> have
 >>> to listen to the Cary, NC noise (NE) at the same time as the
 > generally
 >>> closer and louder Apex, NC noise (S, SE).
 >>> 
 >>> 73, Guy K2AV
 >>> 
 >>> On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson 
 >> wrot

Re: Topband: RFI on TB

[WW3S]

How are you using this on the L ? NO on receive, then apply voltage to close it 
on TX ? When open , does the L float or go to ground?

Sent from my iPad

> On Jul 25, 2019, at 8:36 AM, FZ Bruce  wrote:
> 
> Mark
> Although I am using the RF Parts relay on transmit verticals they work
> great. They are 12 volt DC coils and are marked so on the relay. I
> test checked mine with a little 9 volt battery and pulls great.In the
> advertisement blog it says " Rated coil voltage VDC: 26.5 " This is an
> advertising error. 
> 
> https://www.rfparts.com/vhc3-12v.html [1]
> 
> 73Bruce-k1fz
> 
>-From: "Mark K3MSB" 
> To: "CUTTER DAVID"
> Cc: "Rob Atkinson", "TopBand List", "Guy Olinger K2AV"
> Sent: Thursday July 25 2019 7:59:32AM
> Subject: Re: Topband: RFI on TB
> 
> I’d be interested in hear about this also. I’ve always used ground
> radials for my INV-L but this year I’d like to try an FCP.
> 
> I’ve read that the INV-L as well as the FCP need to be floated
> during
> receive, which means two relays at the INV-L.
> 
> 73 Mark K3MSB
> 
> On Thu, Jul 25, 2019, 4:11 AM CUTTER DAVID via Topband <
> topband@contesting.com> wrote:
> 
>> Guy
>> Slightly OT, but how do you deal with re-radiation from your
> inverted L?
>> I'm about to erect one of your inverted L on FCP and my rx loops
> are about
>> 50m away in the other corner of the field. Is that far enough?
>> David G3UNA/G6CP
>> 
>>> On 24 July 2019 at 07:13 Guy Olinger K2AV  wrote:
>>> 
>>> 
>>> I gotta agree with Rob. An inverted L aerial wire will hear ALL
> the noise
>>> that is around. Mine sure does. RX antenna will help enormously
> if there
>> is
>>> a place to put one that does not get the noise second hand off
> the L. Not
>>> enough room? A bit complicated, but "repeated" noise off the L
> can be
>> dealt
>>> with.
>>> 
>>> The worst noises around here heard on my L were all repaired by
> the power
>>> company. The nastiest noise was very hard to find, I actually
> never
>> "found"
>>> it by looking for it. Noise turned out to be from a bad splice in
> an
>>> underground 13 kV cable going from the 13 kV delta overhead out
> on US 64
>> to
>>> the transformer for my eastern neighbor and next house over. It
> would
>> come
>>> and go with extended cold weather, but never would correlate to
> sunlight
>> or
>>> darkness. I would hear it next to my transformer walking around
> with my
>>> battery K2 and a rubber ducky. It would never locate to up on a
> pole
>> (only
>>> power noise that didn't).
>>> 
>>> Finally the splice hard-arced, exploding the fuse up on the pole
> for the
>>> neighbor's 13 kV feed, and taking those two houses off the grid.
> The
>> noise
>>> went away with the cannon shot noise. Blessed quiet on 160 and
> 80. I had
>>> put up with that for almost four years.
>>> 
>>> In the end, Duke Energy completely reran his AND my buried 13kV
> lines,
>> and
>>> replaced his transformer. 35 years in the ground, 35 year old
> cable
>> design
>>> and materials, and deficient in THEIR opinion. Was really fun to
> watch
>> them
>>> use this super-neat burrowing setup that went right UNDER the
> woods and
>> the
>>> creek (whole other story). Now I can hear the lesser noises on my
> L from
>>> all over Apex and Cary :>) Need RX antenna for sure. That way I
> don't
>> have
>>> to listen to the Cary, NC noise (NE) at the same time as the
> generally
>>> closer and louder Apex, NC noise (S, SE).
>>> 
>>> 73, Guy K2AV
>>> 
>>> On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson 
>> wrote:
>>> 
>>>>> Over past few months, I have picked up an S5-S7 noise
> signature on
>> my TB
>>>> inv
>>>>> L antenna with K2AV FCP system.
>>>> 
>>>> I would not use an inverted L for receiving. Unusable for rx at
> my
>>>> QTH but FB for transmitting.
>>>> 
>>>> 73
>>>> Rob
>>>> K5UJ
>>>> _
>>>> Searchable Archives: http://www.contesting.com/_topband [2] -
> Topband
>>>> Reflector
>>>> 
>>> _
>>> Searchable Archives: http://www.contesting.com/_topband [3] -
> Topband
>> Reflector
>> _
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> Topband
>> Reflector
>> 
> _
> Searchable Archives: http://www.contesting.com/_topband [5] - Topband
> Reflector
> 
> 
> Links:
> --
> [1] https://www.rfparts.com/vhc3-12v.html
> [2] http://www.contesting.com/_topband
> [3] http://www.contesting.com/_topband
> [4] http://www.contesting.com/_topband
> [5] http://www.contesting.com/_topband
> 
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Re: Topband: RFI on TB

[Guy Olinger K2AV]

Hi Mark,

Response to David farther down.

Short answer:  Just one relay, really.

Long answer:

There is a lot of misinformation about FCP's floating around out there,
essentially because most don't know anything at all about FCP's and a
certain few of those keep talking anyway. I don't have a lot of sympathy,
because access to k2av.com is without charge, no entrance exams, and no
passport inspection. International readers constitute the majority of
12,400+ unique readers on k2av.com since September 2017, and they seem to
do well enough with their English skills or Google Translate.

What you have read about separately disconnecting the FCP is hocus for two
reasons:

1)

**IF** you **ARE** using the specified isolation transformer (IsoT) or a
close imitation per the specs on k2av.com, then when the Inv L is
disconnected from the IsoT by a relay, the FCP is ALSO effectively
disconnected.

With the relay open, no signal current can flow through the IsoT antenna
side winding, nothing to flow INTO. If no current in the primary, the
effective R terminating the FCP is very high, nearly as high as it is for
the Inv L.

If you are using some alternate feed system because you don't like IsoT's
for whatever reason, then the answer depends on what you did instead of the
k2av.com specs.

2)

In and of itself, the FCP is really, really, really bad at radiating to the
far field. That's 10 dB per "really". An FCP is a counterpoise, that is to
say an energy reservoir and an awful radiator. Model a pair of FCP's in
series, in free space, at right angles with centers right above one
another. The folding trick employed by an FCP is so good, that it radiates
between -29 and -31 dBi to the far field depending on exactly how the wires
are run. Yes that's MINUS 29 dBi to MINUS 31 dBi (EZNEC Pro/4 v.6, NEC4.2
double precision engine). Let's call that -30 dBi because 1/1000 is
convenient for arithmetic.

If you could get a pair of FCP's into low earth orbit and load up 1500
watts into them, only 1/1000 of that would be radiated as RF. That's 1.5
watts radiated RF and 1498.5 watts radiated as heat from the wire
resistance of the FCP's.

If it is bad at radiating RF, it follows that it will be doubly bad at
re-radiation. To re-radiate, it must first receive. As bad as it is at
radiating, according to physics, it will equally be at receiving. So first
it receives poorly, further diminished by poorly radiating, hence doubly
bad at re-radiation.

73, Guy K2AV

--

Hi, David

RX antennas being affected by re-radiation from a TX antenna is indeed very
much case-by-case, to use a term from earlier in this thread. But the test
is easy. Don't start by installing the relay. The test is too easy.

Find a noisy place on your RX antenna. Somehow get that measured. I'd use
my P3 in various modes. Get your measurements/snapshots, etc.  Then real
quick run out and disconnect the L from the IsoT. Run real quick back in.
Re-listen, re-measure and compare to see if the noise went down. Repeat
this test a good number of times on different days, different conditions,
different orientations, different times of day, etc.

Only start on the relay business if you have a benefit in hand that means
something to YOU,  that is actually improved to a satisfactory degree by
disconnecting the L from the Iso T.

Operating with it is tricky because you don't want your expensive
transceiver/amp transmitting into an open. It's also not good for the relay
contacts to "hot switch". So whatever you might do has to have switching
solved day one.

But it's worth mentioning, and worth testing. Not intended to discourage
getting RX antenna.

73, Guy K2AV
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Tom]

Mark,  

Are you ready to take the red pill or the blue pill?

If you take the red, be prepared to spend endless time and money, and the 
experts on this list will help guide you down the 160m rx rabbit hole.

I was where you were a few years ago... then I started with a k9ay loop, slinky 
antennas, BOGs,  short beverages, K1FZ beverages running into neighbors yards, 
hi-z verticals, NCC-2’s, with no end in sight.

Somehow working stations like VI9NI on 160 at sunrise with no other callers 
make it all worthwhile!

Good Luck
Tom W1TC

> On Jul 24, 2019, at 5:34 PM, Mark - N5OT  wrote:
> 
> This has got to be on a case-by case basis.  I don't have any listening 
> antennas, so i listen on my transmit vertical.  It works fine.  For me.  Most 
> of the time.
> 
> Would I hear more stuff with listening antennas?  I bet the answer is yes 
> under certain conditions.
> 
> 73 - Mark N5OT
> 
> 
>> On 7/24/2019 1:13 AM, Guy Olinger K2AV wrote:
>> I gotta agree with Rob. An inverted L aerial wire will hear ALL the noise
>> that is around. Mine sure does. RX antenna will help enormously if there is
>> a place to put one that does not get the noise second hand off the L. Not
>> enough room? A bit complicated, but "repeated" noise off the L can be dealt
>> with.
>> 
>> The worst noises around here heard on my L were all repaired by the power
>> company. The nastiest noise was very hard to find, I actually never "found"
>> it by looking for it. Noise turned out to be from a bad splice in an
>> underground 13 kV cable going from the 13 kV delta overhead out on US 64 to
>> the transformer for my eastern neighbor and next house over. It would come
>> and go with extended cold weather, but never would correlate to sunlight or
>> darkness. I would hear it next to my transformer walking around with my
>> battery K2 and a rubber ducky. It would never locate to up on a pole (only
>> power noise that didn't).
>> 
>> Finally the splice hard-arced, exploding the fuse up on the pole for the
>> neighbor's 13 kV feed, and taking those two houses off the grid. The noise
>> went away with the cannon shot noise. Blessed quiet on 160 and 80. I had
>> put up with that for almost four years.
>> 
>> In the end, Duke Energy completely reran his AND my buried 13kV lines, and
>> replaced his transformer. 35 years in the ground, 35 year old cable design
>> and materials, and deficient in THEIR opinion. Was really fun to watch them
>> use this super-neat burrowing setup that went right UNDER the woods and the
>> creek (whole other story). Now I can hear the lesser noises on my L from
>> all over Apex and Cary :>)  Need RX antenna for sure. That way I don't have
>> to listen to the Cary, NC noise (NE) at the same time as the generally
>> closer and louder Apex, NC noise (S, SE).
>> 
>> 73, Guy K2AV
>> 
>> On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson  wrote:
>> 
 Over past few months, I have picked up an S5-S7 noise signature on my TB
>>> inv
 L antenna with K2AV FCP system.
>>> I would not use an inverted L for receiving.  Unusable for rx at my
>>> QTH but FB for transmitting.
>>> 
>>> 73
>>> Rob
>>> K5UJ
>>> _
>>> Searchable Archives: http://www.contesting.com/_topband - Topband
>>> Reflector
>>> 
>> _
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> 
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Re: Topband: RFI on TB

[Rob Atkinson]

>This has got to be on a case-by case basis.  I don't have any listening 
>antennas, so i listen on my transmit vertical.  It works fine.  For me.  Most 
>of the time. Would I hear more stuff with listening antennas?  I bet the 
>answer is yes under certain conditions.

Yes under certain circumstances using the tx antenna is okay for rx,
the most obvious example being local communications with a ham a few
miles away.  But I don't know of any serious 160 m. operator who does
not have separate receive antennas.  The reason is that the
reciprocity that allows the tx antenna to also work on rx starts to
break down as we go lower in frequency, beginning on 75 m. but by the
time we tune down to medium wave, it is very noticeable and receiving
becomes more about signal over noise than pure signal strength.  As
new hams, we probably all had the experience of mistakenly tuning
across 160 with the wrong antenna, maybe a 40 m. dipole, and wow, we
hear a lot.   We excitedly hooked up our 160 m. antenna only to hear
nothing, or a lot less.  What went wrong?  Ah, the education begins.

The other problem with the same tx/rx antenna for anyone except the
few lucky ones with no noise sources, is transmitting on top of a QSO
without realizing it.

73
Rob
K5UJ
_
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Re: Topband: RFI on TB

[FZ Bruce]

Mark
Although I am using the RF Parts relay on transmit verticals they work
great. They are 12 volt DC coils and are marked so on the relay. I
test checked mine with a little 9 volt battery and pulls great.In the
advertisement blog it says " Rated coil voltage VDC: 26.5 " This is an
advertising error. 

https://www.rfparts.com/vhc3-12v.html [1]

73Bruce-k1fz

-From: "Mark K3MSB" 
To: "CUTTER DAVID"
Cc: "Rob Atkinson", "TopBand List", "Guy Olinger K2AV"
Sent: Thursday July 25 2019 7:59:32AM
Subject: Re: Topband: RFI on TB

I’d be interested in hear about this also. I’ve always used ground
 radials for my INV-L but this year I’d like to try an FCP.

 I’ve read that the INV-L as well as the FCP need to be floated
during
 receive, which means two relays at the INV-L.

 73 Mark K3MSB

 On Thu, Jul 25, 2019, 4:11 AM CUTTER DAVID via Topband <
 topband@contesting.com> wrote:

 > Guy
 > Slightly OT, but how do you deal with re-radiation from your
inverted L?
 > I'm about to erect one of your inverted L on FCP and my rx loops
are about
 > 50m away in the other corner of the field. Is that far enough?
 > David G3UNA/G6CP
 >
 > > On 24 July 2019 at 07:13 Guy Olinger K2AV  wrote:
 > >
 > >
 > > I gotta agree with Rob. An inverted L aerial wire will hear ALL
the noise
 > > that is around. Mine sure does. RX antenna will help enormously
if there
 > is
 > > a place to put one that does not get the noise second hand off
the L. Not
 > > enough room? A bit complicated, but "repeated" noise off the L
can be
 > dealt
 > > with.
 > >
 > > The worst noises around here heard on my L were all repaired by
the power
 > > company. The nastiest noise was very hard to find, I actually
never
 > "found"
 > > it by looking for it. Noise turned out to be from a bad splice in
an
 > > underground 13 kV cable going from the 13 kV delta overhead out
on US 64
 > to
 > > the transformer for my eastern neighbor and next house over. It
would
 > come
 > > and go with extended cold weather, but never would correlate to
sunlight
 > or
 > > darkness. I would hear it next to my transformer walking around
with my
 > > battery K2 and a rubber ducky. It would never locate to up on a
pole
 > (only
 > > power noise that didn't).
 > >
 > > Finally the splice hard-arced, exploding the fuse up on the pole
for the
 > > neighbor's 13 kV feed, and taking those two houses off the grid.
The
 > noise
 > > went away with the cannon shot noise. Blessed quiet on 160 and
80. I had
 > > put up with that for almost four years.
 > >
 > > In the end, Duke Energy completely reran his AND my buried 13kV
lines,
 > and
 > > replaced his transformer. 35 years in the ground, 35 year old
cable
 > design
 > > and materials, and deficient in THEIR opinion. Was really fun to
watch
 > them
 > > use this super-neat burrowing setup that went right UNDER the
woods and
 > the
 > > creek (whole other story). Now I can hear the lesser noises on my
L from
 > > all over Apex and Cary :>) Need RX antenna for sure. That way I
don't
 > have
 > > to listen to the Cary, NC noise (NE) at the same time as the
generally
 > > closer and louder Apex, NC noise (S, SE).
 > >
 > > 73, Guy K2AV
 > >
 > > On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson 
 > wrote:
 > >
 > > > > Over past few months, I have picked up an S5-S7 noise
signature on
 > my TB
 > > > inv
 > > > > L antenna with K2AV FCP system.
 > > >
 > > > I would not use an inverted L for receiving. Unusable for rx at
my
 > > > QTH but FB for transmitting.
 > > >
 > > > 73
 > > > Rob
 > > > K5UJ
 > > > _
 > > > Searchable Archives: http://www.contesting.com/_topband [2] -
Topband
 > > > Reflector
 > > >
 > > _
 > > Searchable Archives: http://www.contesting.com/_topband [3] -
Topband
 > Reflector
 > _
 > Searchable Archives: http://www.contesting.com/_topband [4] -
Topband
 > Reflector
 >
 _
 Searchable Archives: http://www.contesting.com/_topband [5] - Topband
Reflector
 

Links:
--
[1] https://www.rfparts.com/vhc3-12v.html
[2] http://www.contesting.com/_topband
[3] http://www.contesting.com/_topband
[4] http://www.contesting.com/_topband
[5] http://www.contesting.com/_topband

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Re: Topband: RFI on TB

[Mark K3MSB]

I’d be interested in hear about this also.   I’ve always used ground
radials for my INV-L but this year I’d like to try an FCP.

I’ve read that the INV-L as well as the FCP need to be floated during
receive,  which means two relays at the INV-L.

 73 Mark K3MSB

On Thu, Jul 25, 2019, 4:11 AM CUTTER DAVID via Topband <
topband@contesting.com> wrote:

> Guy
> Slightly OT, but how do you deal with re-radiation from your inverted L?
> I'm about to erect one of your inverted L on FCP and my rx loops are about
> 50m away in the other corner of the field. Is that far enough?
> David G3UNA/G6CP
>
> > On 24 July 2019 at 07:13 Guy Olinger K2AV  wrote:
> >
> >
> > I gotta agree with Rob. An inverted L aerial wire will hear ALL the noise
> > that is around. Mine sure does. RX antenna will help enormously if there
> is
> > a place to put one that does not get the noise second hand off the L. Not
> > enough room? A bit complicated, but "repeated" noise off the L can be
> dealt
> > with.
> >
> > The worst noises around here heard on my L were all repaired by the power
> > company. The nastiest noise was very hard to find, I actually never
> "found"
> > it by looking for it. Noise turned out to be from a bad splice in an
> > underground 13 kV cable going from the 13 kV delta overhead out on US 64
> to
> > the transformer for my eastern neighbor and next house over. It would
> come
> > and go with extended cold weather, but never would correlate to sunlight
> or
> > darkness. I would hear it next to my transformer walking around with my
> > battery K2 and a rubber ducky. It would never locate to up on a pole
> (only
> > power noise that didn't).
> >
> > Finally the splice hard-arced, exploding the fuse up on the pole for the
> > neighbor's 13 kV feed, and taking those two houses off the grid. The
> noise
> > went away with the cannon shot noise. Blessed quiet on 160 and 80. I had
> > put up with that for almost four years.
> >
> > In the end, Duke Energy completely reran his AND my buried 13kV lines,
> and
> > replaced his transformer. 35 years in the ground, 35 year old cable
> design
> > and materials, and deficient in THEIR opinion. Was really fun to watch
> them
> > use this super-neat burrowing setup that went right UNDER the woods and
> the
> > creek (whole other story). Now I can hear the lesser noises on my L from
> > all over Apex and Cary :>)  Need RX antenna for sure. That way I don't
> have
> > to listen to the Cary, NC noise (NE) at the same time as the generally
> > closer and louder Apex, NC noise (S, SE).
> >
> > 73, Guy K2AV
> >
> > On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson 
> wrote:
> >
> > > > Over past few months, I have picked up an S5-S7 noise signature on
> my TB
> > > inv
> > > > L antenna with K2AV FCP system.
> > >
> > > I would not use an inverted L for receiving.  Unusable for rx at my
> > > QTH but FB for transmitting.
> > >
> > > 73
> > > Rob
> > > K5UJ
> > > _
> > > Searchable Archives: http://www.contesting.com/_topband - Topband
> > > Reflector
> > >
> > _
> > Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
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Re: Topband: RFI on TB

[CUTTER DAVID via Topband]

Guy
Slightly OT, but how do you deal with re-radiation from your inverted L?  
I'm about to erect one of your inverted L on FCP and my rx loops are about 50m 
away in the other corner of the field. Is that far enough?
David G3UNA/G6CP

> On 24 July 2019 at 07:13 Guy Olinger K2AV  wrote:
> 
> 
> I gotta agree with Rob. An inverted L aerial wire will hear ALL the noise
> that is around. Mine sure does. RX antenna will help enormously if there is
> a place to put one that does not get the noise second hand off the L. Not
> enough room? A bit complicated, but "repeated" noise off the L can be dealt
> with.
> 
> The worst noises around here heard on my L were all repaired by the power
> company. The nastiest noise was very hard to find, I actually never "found"
> it by looking for it. Noise turned out to be from a bad splice in an
> underground 13 kV cable going from the 13 kV delta overhead out on US 64 to
> the transformer for my eastern neighbor and next house over. It would come
> and go with extended cold weather, but never would correlate to sunlight or
> darkness. I would hear it next to my transformer walking around with my
> battery K2 and a rubber ducky. It would never locate to up on a pole (only
> power noise that didn't).
> 
> Finally the splice hard-arced, exploding the fuse up on the pole for the
> neighbor's 13 kV feed, and taking those two houses off the grid. The noise
> went away with the cannon shot noise. Blessed quiet on 160 and 80. I had
> put up with that for almost four years.
> 
> In the end, Duke Energy completely reran his AND my buried 13kV lines, and
> replaced his transformer. 35 years in the ground, 35 year old cable design
> and materials, and deficient in THEIR opinion. Was really fun to watch them
> use this super-neat burrowing setup that went right UNDER the woods and the
> creek (whole other story). Now I can hear the lesser noises on my L from
> all over Apex and Cary :>)  Need RX antenna for sure. That way I don't have
> to listen to the Cary, NC noise (NE) at the same time as the generally
> closer and louder Apex, NC noise (S, SE).
> 
> 73, Guy K2AV
> 
> On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson  wrote:
> 
> > > Over past few months, I have picked up an S5-S7 noise signature on my TB
> > inv
> > > L antenna with K2AV FCP system.
> >
> > I would not use an inverted L for receiving.  Unusable for rx at my
> > QTH but FB for transmitting.
> >
> > 73
> > Rob
> > K5UJ
> > _
> > Searchable Archives: http://www.contesting.com/_topband - Topband
> > Reflector
> >
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
_
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Re: Topband: RFI on TB

[Mark - N5OT]

This has got to be on a case-by case basis.  I don't have any listening 
antennas, so i listen on my transmit vertical.  It works fine.  For me.  
Most of the time.


Would I hear more stuff with listening antennas?  I bet the answer is 
yes under certain conditions.


73 - Mark N5OT


On 7/24/2019 1:13 AM, Guy Olinger K2AV wrote:

I gotta agree with Rob. An inverted L aerial wire will hear ALL the noise
that is around. Mine sure does. RX antenna will help enormously if there is
a place to put one that does not get the noise second hand off the L. Not
enough room? A bit complicated, but "repeated" noise off the L can be dealt
with.

The worst noises around here heard on my L were all repaired by the power
company. The nastiest noise was very hard to find, I actually never "found"
it by looking for it. Noise turned out to be from a bad splice in an
underground 13 kV cable going from the 13 kV delta overhead out on US 64 to
the transformer for my eastern neighbor and next house over. It would come
and go with extended cold weather, but never would correlate to sunlight or
darkness. I would hear it next to my transformer walking around with my
battery K2 and a rubber ducky. It would never locate to up on a pole (only
power noise that didn't).

Finally the splice hard-arced, exploding the fuse up on the pole for the
neighbor's 13 kV feed, and taking those two houses off the grid. The noise
went away with the cannon shot noise. Blessed quiet on 160 and 80. I had
put up with that for almost four years.

In the end, Duke Energy completely reran his AND my buried 13kV lines, and
replaced his transformer. 35 years in the ground, 35 year old cable design
and materials, and deficient in THEIR opinion. Was really fun to watch them
use this super-neat burrowing setup that went right UNDER the woods and the
creek (whole other story). Now I can hear the lesser noises on my L from
all over Apex and Cary :>)  Need RX antenna for sure. That way I don't have
to listen to the Cary, NC noise (NE) at the same time as the generally
closer and louder Apex, NC noise (S, SE).

73, Guy K2AV

On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson  wrote:


Over past few months, I have picked up an S5-S7 noise signature on my TB

inv

L antenna with K2AV FCP system.

I would not use an inverted L for receiving.  Unusable for rx at my
QTH but FB for transmitting.

73
Rob
K5UJ
_
Searchable Archives: http://www.contesting.com/_topband - Topband
Reflector


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_
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Re: Topband: RFI on TB

[Guy Olinger K2AV]

I gotta agree with Rob. An inverted L aerial wire will hear ALL the noise
that is around. Mine sure does. RX antenna will help enormously if there is
a place to put one that does not get the noise second hand off the L. Not
enough room? A bit complicated, but "repeated" noise off the L can be dealt
with.

The worst noises around here heard on my L were all repaired by the power
company. The nastiest noise was very hard to find, I actually never "found"
it by looking for it. Noise turned out to be from a bad splice in an
underground 13 kV cable going from the 13 kV delta overhead out on US 64 to
the transformer for my eastern neighbor and next house over. It would come
and go with extended cold weather, but never would correlate to sunlight or
darkness. I would hear it next to my transformer walking around with my
battery K2 and a rubber ducky. It would never locate to up on a pole (only
power noise that didn't).

Finally the splice hard-arced, exploding the fuse up on the pole for the
neighbor's 13 kV feed, and taking those two houses off the grid. The noise
went away with the cannon shot noise. Blessed quiet on 160 and 80. I had
put up with that for almost four years.

In the end, Duke Energy completely reran his AND my buried 13kV lines, and
replaced his transformer. 35 years in the ground, 35 year old cable design
and materials, and deficient in THEIR opinion. Was really fun to watch them
use this super-neat burrowing setup that went right UNDER the woods and the
creek (whole other story). Now I can hear the lesser noises on my L from
all over Apex and Cary :>)  Need RX antenna for sure. That way I don't have
to listen to the Cary, NC noise (NE) at the same time as the generally
closer and louder Apex, NC noise (S, SE).

73, Guy K2AV

On Tue, Jul 23, 2019 at 9:37 AM Rob Atkinson  wrote:

> > Over past few months, I have picked up an S5-S7 noise signature on my TB
> inv
> > L antenna with K2AV FCP system.
>
> I would not use an inverted L for receiving.  Unusable for rx at my
> QTH but FB for transmitting.
>
> 73
> Rob
> K5UJ
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
_
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Re: Topband: RFI on TB

[k3ky]

Rumor has it PG is facing possible bankruptcy due to being
found responsible for the big fire(s) in CA. That being the
case, I would expect they would have to re-prioritize greatly-
problems such as yours are, to them, 'lost in their noise'
(pun intended).

73, David K3KY




(You wrote:)


I want to know how you guys get the power company to respond so quickly.
I’ve been calling Pacific Gas and Electric for 6 weeks now and
nothing.
I can’t even get a phone call.


Ken K6MR
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Chuck Dietz]

In the Houston, Texas area the hams know the cell number of the guy who
works for the electric distribution company locating the noise sources. We
can call him and leave a very detailed message about the noise source
location and he is quick to verify it and have it repaired. Ask around.

Logan Dietz W5PR

On Tue, Jul 23, 2019 at 12:03 PM Ken K6MR  wrote:

> I want to know how you guys get the power company to respond so quickly.
> I’ve been calling Pacific Gas and Electric for 6 weeks now and nothing.  I
> can’t even get a phone call.
>
>
>
> Ken K6MR
>
>
>
> 
> From: Topband  on behalf of K4SAV <
> radi...@charter.net>
> Sent: Tuesday, July 23, 2019 8:43:56 AM
> To: topband@contesting.com
> Subject: Re: Topband: RFI on TB
>
>
> Don't know why the mail system thinks this message is spam... Trying again.
>
> Lightning surge suppressor on power poles can be big noise generators
> when they go bad.  The worst one I found was three miles from my house
> and created S9 noise on my receiving array.  Its characteristics fooled
> me at first because it didn't sound like something a power pole could
> generate.  It sounded like someone holding down the dash lever on a
> keyer set at about 10 wpm and running continuously 24/7.  Then one day I
> heard it break into a more random pattern.  That's when I went looking
> for it.
>
> Found it easily because of the huge noise signature.  Called it in to
> the power company, gave them the pole number and which component on the
> pole was at fault.  Went back home and turned on the radio and the noise
> was gone.  Couldn't believe that so I drove back to the pole and they
> had already disconnected the surge suppressor. Best repair time ever.
>
> I use an MFJ-856 to get close and a homebrew ultrasonic detector to
> identify the exact component on the pole.  MFJ also now makes an
> ultrasonic detector, the MFJ-5008.
>
> Jerry, K4SAV
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
> _
> Searchable Archives: http://www.contesting.com/_topband - Topband
> Reflector
>
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Re: Topband: RFI on TB

[Ken K6MR]

I want to know how you guys get the power company to respond so quickly.  I’ve 
been calling Pacific Gas and Electric for 6 weeks now and nothing.  I can’t 
even get a phone call.



Ken K6MR




From: Topband  on behalf of K4SAV 

Sent: Tuesday, July 23, 2019 8:43:56 AM
To: topband@contesting.com
Subject: Re: Topband: RFI on TB


Don't know why the mail system thinks this message is spam... Trying again.

Lightning surge suppressor on power poles can be big noise generators
when they go bad.  The worst one I found was three miles from my house
and created S9 noise on my receiving array.  Its characteristics fooled
me at first because it didn't sound like something a power pole could
generate.  It sounded like someone holding down the dash lever on a
keyer set at about 10 wpm and running continuously 24/7.  Then one day I
heard it break into a more random pattern.  That's when I went looking
for it.

Found it easily because of the huge noise signature.  Called it in to
the power company, gave them the pole number and which component on the
pole was at fault.  Went back home and turned on the radio and the noise
was gone.  Couldn't believe that so I drove back to the pole and they
had already disconnected the surge suppressor. Best repair time ever.

I use an MFJ-856 to get close and a homebrew ultrasonic detector to
identify the exact component on the pole.  MFJ also now makes an
ultrasonic detector, the MFJ-5008.

Jerry, K4SAV
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
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Re: Topband: RFI on TB

[K4SAV]

Don't know why the mail system thinks this message is spam... Trying again.

Lightning surge suppressor on power poles can be big noise generators 
when they go bad.  The worst one I found was three miles from my house 
and created S9 noise on my receiving array.  Its characteristics fooled 
me at first because it didn't sound like something a power pole could 
generate.  It sounded like someone holding down the dash lever on a 
keyer set at about 10 wpm and running continuously 24/7.  Then one day I 
heard it break into a more random pattern.  That's when I went looking 
for it.


Found it easily because of the huge noise signature.  Called it in to 
the power company, gave them the pole number and which component on the 
pole was at fault.  Went back home and turned on the radio and the noise 
was gone.  Couldn't believe that so I drove back to the pole and they 
had already disconnected the surge suppressor. Best repair time ever.


I use an MFJ-856 to get close and a homebrew ultrasonic detector to 
identify the exact component on the pole.  MFJ also now makes an 
ultrasonic detector, the MFJ-5008.


Jerry, K4SAV
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Rob Atkinson]

> Over past few months, I have picked up an S5-S7 noise signature on my TB inv
> L antenna with K2AV FCP system.

I would not use an inverted L for receiving.  Unusable for rx at my
QTH but FB for transmitting.

73
Rob
K5UJ
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Mark - N5OT]

I can relate the same story here.  The power company guy came by, I 
showed him what direction it was coming from, he went to the nearest 
pole with a lightning arrestor in that direction (a little over a 
quarter mile away - not every pole has one) disconnected the lightning 
arrestor, and the noise went away.  He said that was a common failure 
mode for those things, he would leave it disconnected, then, just like 
Jeff said, he said he would slate it for replacement before next storm 
season.  That was the last I ever heard of that noise.


Things went from miserable to smiling in about a half hour.

You might have the "noise signature on the shield of your coax" but it 
may be possible that if he disconnects the lightning arrestor your 
system will revert to its previous satisfactory state without making 
changes to your system.


I think what made my experience go well was that I was able to show the 
guy the noise, indicate where it was coming from, and confirm that his 
action stopped the noise.  I was using a portable battery powered VHF 
receiver set to AM, plus and a handheld direction finding yagi antenna 
to gather my data.  Plus a little driving around.  I was using 160 
meters to show him how useless the noise source made my radio, then how 
fabulous it was when he was done.  His name and number are now in my 
speed dial.


73 - Mark N5OT


On 7/22/2019 10:15 PM, Jeff Blaine wrote:
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.  The good news is if your experience is similar to 
mine, the power company will be able to fix your noise maker and the 
difference is almost literally night and day.


73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com


On 7/22/19 7:33 PM, Richard (Rick) Karlquist wrote:



On 7/22/2019 3:59 PM, 57jndenn...@comcast.net wrote:


I am uncertain this will cure problem, My TB and yagi coax shields are
showing a noise signature on his analyzer.

This was a shock as both coax cables have commercial bead type choke 
baluns.



Jim K7EG


I'm not shocked.
Bead type choke baluns are rarely effective on 160 meters.
Refer to K9YC's handbook (or read his prolific posts to this
reflector) to learn how to make effective chokes using large
toroids as opposed to beads.

Rick N6RK
_
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Reflector



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Reflector


_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Jeff Blaine]

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.  The good news is if your experience is similar to mine, the 
power company will be able to fix your noise maker and the difference is 
almost literally night and day.


73/jeff/ac0c
alpha-charlie-zero-charlie
www.ac0c.com


On 7/22/19 7:33 PM, Richard (Rick) Karlquist wrote:



On 7/22/2019 3:59 PM, 57jndenn...@comcast.net wrote:


I am uncertain this will cure problem, My TB and yagi coax shields are
showing a noise signature on his analyzer.

This was a shock as both coax cables have commercial bead type choke 
baluns.



Jim K7EG


I'm not shocked.
Bead type choke baluns are rarely effective on 160 meters.
Refer to K9YC's handbook (or read his prolific posts to this
reflector) to learn how to make effective chokes using large
toroids as opposed to beads.

Rick N6RK
_
Searchable Archives: http://www.contesting.com/_topband - Topband 
Reflector



_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Re: Topband: RFI on TB

[Richard (Rick) Karlquist]

On 7/22/2019 3:59 PM, 57jndenn...@comcast.net wrote:


I am uncertain this will cure problem, My TB and yagi coax shields are
showing a noise signature on his analyzer.

This was a shock as both coax cables have commercial bead type choke baluns.



Jim K7EG


I'm not shocked.
Bead type choke baluns are rarely effective on 160 meters.
Refer to K9YC's handbook (or read his prolific posts to this
reflector) to learn how to make effective chokes using large
toroids as opposed to beads.

Rick N6RK
_
Searchable Archives: http://www.contesting.com/_topband - Topband Reflector

Topband: RFI on TB

[57JNDenneny]

Over past few months, I have picked up an S5-S7 noise signature on my TB inv
L antenna with K2AV FCP system.  This configuration has been working
trouble-free for a couple years.  Power company sent consultant today who
located a noisy power pole.

 

I am uncertain this will cure problem, My TB and yagi coax shields are
showing a noise signature on his analyzer.

 

This was a shock as both coax cables have commercial bead type choke baluns.
I have theee ground rods close together out side of shack.  Coax shield is
grounded at radio end only for both  cables.  I am not certain how to
proceed.

 

Jim K7EG

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