Re: Topband: What have I done?

[Carl Braun]

Thanks for the response and the calculations Don. Lots of offline responses to 
my query.

The antennas use 90 radials 40' to 150' with the average at 66'

Your option B is the way I configured the L network and your numbers are very 
close to mine.

The second variable cap was set aside to use the smaller one.

I'm going to try and roll my own inductor and apply a 70pF cap to gnd or 
variable cap to resonate

Wish me luck

Thanks

Carl AG6X

Sent from my iPhone

On Feb 14, 2016, at 11:56 PM, "Don Kirk" 
> wrote:

Hi Carl,

Does not appear anyone has answered you, so let me give it a quick shot while 
between flights in Japan.  I'm somewhat confused with your final L network 
configuration because you mentioned one capacitor, and then a second capacitor 
without mentioning if you still had the first capacitor in your configuration, 
etc.  You also did not mention what L network configuration you used (see 
below).

Therefore I started from scratch to see what a 64 foot vertical wire would look 
like at 7.050 Mhz to see what kind of L network would be required to convert 
its impedance to a pure 50 ohms resistance.

Using EZNEC demo, I approximate a 64 foot vertical wire on 7.050 Mhz has an 
input impedance of approximately 1274 +j1436 ohms when just using a ground rod 
with medium soil (because this antenna has such a high input impedance it 
really does not matter what I use for ground conductivity).

Then using an online L network calculator I come up with the following two 
different L network configurations you could use to match to a 50 ohm resistive 
source.

L network with inductor between bottom of 64 foot vertical and ground.
L = 10.18 uh
C = 59.9 pf

L network with capacitor between bottom of 64 foot vertical and ground.
L = 8.5 uh
C = 67.6 pf

Not sure what L network configuration you used, but does it sound like I 
closely replicated what you have based upon one of the above mentioned L 
network configurations?  If not, then please better describe your configuration.

Please advise so we can better answer your question, and hopefully I have not 
messed something up with my quick analysis/approximation.

Don (wd8dsb)




On Sat, Feb 13, 2016 at 4:53 PM, Carl Braun 
> wrote:
I have revised my question to correct the length of the antenna in question


Topbanders

In the past, I've posted some questions related to making my 80 meter verticals 
(64' tall ground mounted) work on different bands.  The pair is spaced at ¼ wl 
on 80m and then I switch in base loading to resonate the same pair on 160m 
which are then effectively spaced at 1/8 wl.   Now I want to make them work on 
40m which would have them resonate as ½ or 5/8 wl and would have an effective 
spacing at ½ wl.

So this is what I did...I installed an L network off of the vertical 
effectively tuning a 64' stick of aluminum to 7.050.  It took me a couple of 
tries as the first 1500pF (monster) variable capacitor wouldn't get down low 
enough to get me flat.  I had another 50-150pF Johnson variable cap available 
so I tried that and got the antenna to tune to 46 ohms at j+0.Inside the 
shack I see 1.0:1 Vswr from 7.000 to 7.290...wow!

I measured the cap and it came to 70pf.  My cheapie Chinese meter doesn't 
register anything on the L scale but I have 7 turns on a 3 ½" inductor. The 
full coil is 33 uH at 25 turns so I estimate 8-12 uH of inductance.

But what have I done? Have I resonated a ½ wl antenna or have I resonated 
something else like a 5/8 wl antenna with the added inductance?

I plan on treating them as ½ wl spaced phased verticals on 40 and feeding them 
with equal lengths of ¾ wl feedlines for broadside phasing and then adding an 
additional 2/4 wl to get my 180 degree shift for end fire.

Please share your comments.

thanks

Carl de AG6X

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Re: Topband: Tecsun 660

[Kenneth Grimm]

That reminds me of an episode that happened here a while back. When I got
serious about top band I discovered that the noise was too much.  I tracked
down the offending power poles using the method you mentioned.  Noted the
pole numbers from the metal tags that were attached.  Called APCO and in a
couple of days they were out here and quickly verified my findings and
fixed the problems.  A year or so later, we lost power and I called APCO.
They responded very quickly and discoverd that a squirrel had committed
"harikari" and tripped the breaker on the pole.  As they were finishing up,
I went out to thank them and the lineman said, "Oh, you are the guy who
saved us so much time when we came out to fix the hardware on the noisy
poles."  Made my day!

Ken - K4XL

On Tue, Feb 16, 2016 at 4:24 PM,  wrote:

> Hi Stan,
>
>
> There are countless thousands of poles within five miles of my
> QTH, his method could not possibly work here. If I tried, I
> would lose my excellent reputation with my power company
> RFI crew.
>
>
>
> I prefer to leave my shack and verify the pole rather than guessing
> which one it might be. Its not difficult and a little exercise is a
> good thing!
>
>
> tks
>
>
> 73
> Frank
> W3LPL
>
> --
Ken - K4XL
BoatAnchor Manual Archive
BAMA - http://bama.edebris.com

"Show me a politician who is poor, and I'll show you a poor
politician." - Carlos
Hank González
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Re: Topband: Tecsun 660

[donovanf]

Hi Stan, 


There are countless thousands of poles within five miles of my 
QTH, his method could not possibly work here. If I tried, I 
would lose my excellent reputation with my power company 
RFI crew. 



I prefer to leave my shack and verify the pole rather than guessing 
which one it might be. Its not difficult and a little exercise is a 
good thing! 


tks 


73 
Frank 
W3LPL 

- Original Message -

From: "Stan Stockton"  
To: donov...@starpower.net 
Cc: "Top Band Contesting" , r...@contesting.com 
Sent: Tuesday, February 16, 2016 5:19:55 PM 
Subject: Re: Topband: Tecsun 660 

Frank, 

I have a friend who has used the RF Gain control as needed, balanced antenna 
and accurate, equal measurement of the strength of the noise off center by an 
equal number of degrees CW and CCW from the actual direction to determine with 
great accuracy the direction of the noise. Then plotting a line using GPS 
mapping has actually called the power company telling them the exact pole where 
the problem is located without ever leaving his shack. He said he could have 
given them the pole number where the line went right through the pole on the 
map except for the fact that they had blacked out the number like they do on 
license plates. The address had to suffice. Pretty neat! 

73... Stan, K5GO 

> On Feb 16, 2016, at 9:18 AM, donov...@starpower.net wrote: 
> 
> Hi Jeff, 
> 
> 
> My consistent practice is to identify the highest frequency where 
> I can hear the RFI in my shack. I then use my directive antennas 
> to determine the bearing on which I should search. I can 
> consistently determine azimuth within better than ten degree 
> accuracy on any band. I begin my search on that frequency 
> with the PL-660 in wide band AM mode, walking or driving 
> along the line of bearing. 
> 
> 
> The PL-660 has a built in loopstick antenna very useful for 
> direction finding but active only in the AM broadcast band 
> (540-1700 kHz). Above 1700 kHz it uses a short retractable 
> whip antenna (slightly useful for direction finding) or an 
> external antenna. 
> 
> 
> Usually (but definitely not always) the RFI can be heard on higher 
> frequencies as you get closer to the source, in many cases up the 
> the aircraft band or all the way up to 450 MHz (on a different 
> receiver). So far my most distant RFI was AC power line RFI 
> very strong at my QTH that originates four miles away, It was 
> a serious visible arc on a 34 kV subtransmission line (not a local 
> 13 kV distribution line). The power company was very 
> motivated to repair it quickly. 
> 
> 
> This recent RFI was very different than anything I've ever 
> experienced, I could hear the RFI only on the 160 meter band 
> (about 1500- 2000 kHz) It sounded like white noise with no 
> audible 60 Hz (or 60 Hz harmonic) component, The only 
> way I could locate it was by using the PL-660 S-meter with 
> the PL-660 in wideband AM mode. It turned out to be a 
> malfunctioning Travellers' Information Station transmitter 
> at 1700 kHz. Local hams have an excellent relationship with 
> the county Office of Emergency Management that operates the 
> transmitter and they turned it off within hours of being notified 
> of the problem. 
> 
> 
> This is only the second RFI that I've experienced that affects 
> only 160 meters. The first one was very intense RFI that 
> sounded exactly like classic AC power line RFI but strangely 
> it affected only 160 meters and the AM broadcast band. 
> It turned out to be a malfunctioning electric fence charger 
> one mile away that was stuck continuously on, not pulsing. 
> Unfortunately the landowner (an electrician!) was very 
> belligerent about refusing to replace his fence charger, but 
> some aggressive "social engineering" motivated him to 
> change his behavior. 
> 
> 
> 73 
> Frank 
> W3LPL 
> 
> 
> - Original Message - 
> 
> From: k...@aol.com 
> To: donov...@starpower.net 
> Sent: Tuesday, February 16, 2016 10:08:22 AM 
> Subject: Tecsun 660 
> 
> Hi Frank 
> 
> I read your emails on your RFI search. 
> 
> Youmay have mentioned it, but what FREQ BAND did you use on the TECSUN in 
> your search for the source? 
> 
> Was it the AIRCRAFT BAND on FM? 
> 
> The reason I ask is that I have a similar radio - that is very similar to 
> the radio you used - just made by SONY. 
> 
> I wonder if I could use it like you did? I am 99% sure it has the aricraft 
> FM band in it. 
> 
> Pls let me know when you can. 
> 
> Tks 
> 
> 73 JEFF 
> 
> _ 
> Topband Reflector Archives - http://www.contesting.com/_topband 

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Re: Topband: Tecsun 660

[Stan Stockton]

Frank,

I have a friend who has used the RF Gain control as needed, balanced antenna 
and accurate, equal measurement of the strength of the noise off center by an 
equal number of degrees CW and CCW from the actual direction to determine with 
great accuracy the direction of the noise.  Then plotting a line using GPS 
mapping has actually called the power company telling them the exact pole where 
the problem is located without ever leaving his shack.  He said he could have 
given them the pole number where the line went right through the pole on the 
map except for the fact that they had blacked out the number like they do on 
license plates.  The address had to suffice.  Pretty neat!

73... Stan, K5GO

> On Feb 16, 2016, at 9:18 AM, donov...@starpower.net wrote:
> 
> Hi Jeff, 
> 
> 
> My consistent practice is to identify the highest frequency where 
> I can hear the RFI in my shack. I then use my directive antennas 
> to determine the bearing on which I should search. I can 
> consistently determine azimuth within better than ten degree 
> accuracy on any band. I begin my search on that frequency 
> with the PL-660 in wide band AM mode, walking or driving 
> along the line of bearing. 
> 
> 
> The PL-660 has a built in loopstick antenna very useful for 
> direction finding but active only in the AM broadcast band 
> (540-1700 kHz). Above 1700 kHz it uses a short retractable 
> whip antenna (slightly useful for direction finding) or an 
> external antenna. 
> 
> 
> Usually (but definitely not always) the RFI can be heard on higher 
> frequencies as you get closer to the source, in many cases up the 
> the aircraft band or all the way up to 450 MHz (on a different 
> receiver). So far my most distant RFI was AC power line RFI 
> very strong at my QTH that originates four miles away, It was 
> a serious visible arc on a 34 kV subtransmission line (not a local 
> 13 kV distribution line). The power company was very 
> motivated to repair it quickly. 
> 
> 
> This recent RFI was very different than anything I've ever 
> experienced, I could hear the RFI only on the 160 meter band 
> (about 1500- 2000 kHz) It sounded like white noise with no 
> audible 60 Hz (or 60 Hz harmonic) component, The only 
> way I could locate it was by using the PL-660 S-meter with 
> the PL-660 in wideband AM mode. It turned out to be a 
> malfunctioning Travellers' Information Station transmitter 
> at 1700 kHz. Local hams have an excellent relationship with 
> the county Office of Emergency Management that operates the 
> transmitter and they turned it off within hours of being notified 
> of the problem. 
> 
> 
> This is only the second RFI that I've experienced that affects 
> only 160 meters. The first one was very intense RFI that 
> sounded exactly like classic AC power line RFI but strangely 
> it affected only 160 meters and the AM broadcast band. 
> It turned out to be a malfunctioning electric fence charger 
> one mile away that was stuck continuously on, not pulsing. 
> Unfortunately the landowner (an electrician!) was very 
> belligerent about refusing to replace his fence charger, but 
> some aggressive "social engineering" motivated him to 
> change his behavior. 
> 
> 
> 73 
> Frank 
> W3LPL 
> 
> 
> - Original Message -
> 
> From: k...@aol.com 
> To: donov...@starpower.net 
> Sent: Tuesday, February 16, 2016 10:08:22 AM 
> Subject: Tecsun 660 
> 
> Hi Frank 
> 
> I read your emails on your RFI search. 
> 
> Youmay have mentioned it, but what FREQ BAND did you use on the TECSUN in 
> your search for the source? 
> 
> Was it the AIRCRAFT BAND on FM? 
> 
> The reason I ask is that I have a similar radio - that is very similar to 
> the radio you used - just made by SONY. 
> 
> I wonder if I could use it like you did? I am 99% sure it has the aricraft 
> FM band in it. 
> 
> Pls let me know when you can. 
> 
> Tks 
> 
> 73 JEFF 
> 
> _
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Re: Topband: Antenna Tuners

[Grant Saviers]

I cut my top loaded "T" (85' at top, 10' high feed, elevated 8x 125' 
radials) for 1825.  Then 3 equal value series capacitors are shorted by 
PCB relays (10a, 5Kv coil insulation) to switch in C, C/2, and C/3 
(C=4000pf for this antenna).  That yields 4 by 40KHz spaced segments 
with > 50KHz 2:1 bandwidth for full band coverage (I don't cover above 
1980).  The feed is 25 ohms with a TLT with a 1.1:1 resonance swr, and 
the caps are on the low Z side (higher current, lower voltage).   I 
paralleled silver micas to get an adequate current rating.  EZNEC shows 
the C, currents and voltages needed, all reasonable with the correct 
micas.  The relays never hot switch and are mounted in a plastic water 
tight box at the feedpoint.  So far so good at QRO and 3 years of casual 
operations. I used a 4 position rotary switch and some diodes to select 
the relays.  My amp has a tuner that is ok < 2:1 swr, but the idea (not 
mine) can be morphed to whatever frequencies desired if a tuner isn't used.


Grant KZ1W



On 2/16/2016 6:50 AM, Tim Shoppa wrote:

Jim, I mentioned relay cut-in of L's and/or C's at the base of an antenna
to help cover all of 160M. On my tuner web page I mentioned does not show
this recent update I have made at my shack, but I have a relay that shunts
out turns of my 160M coil to help me QSY to top end of 160M phone in
contests.

Another choice that I left out, if you want to QSY all the way between 1800
and 2000 kc with a limited-bandwidth antenna, is relay-cut-in-and-out of
extra length at the top of the antenna. There have been QST articles, as
well as some write-ups on this mailing list, about doing this. The
electrical voltages involved, as well as complications of remotely
controlling relays at the top of an antenna, have made this a non-choice at
my station. I'm very self-satisfied about my relays at the base of my
antenna but the complications of high-voltage relays at the top of an
antenna, is not something I've done myself.

Tim N3QE

On Tue, Feb 16, 2016 at 9:05 AM, Tim Shoppa  wrote:



...snip..
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Re: Topband: Tecsun 660

[donovanf]

Hi Jeff, 


My consistent practice is to identify the highest frequency where 
I can hear the RFI in my shack. I then use my directive antennas 
to determine the bearing on which I should search. I can 
consistently determine azimuth within better than ten degree 
accuracy on any band. I begin my search on that frequency 
with the PL-660 in wide band AM mode, walking or driving 
along the line of bearing. 


The PL-660 has a built in loopstick antenna very useful for 
direction finding but active only in the AM broadcast band 
(540-1700 kHz). Above 1700 kHz it uses a short retractable 
whip antenna (slightly useful for direction finding) or an 
external antenna. 


Usually (but definitely not always) the RFI can be heard on higher 
frequencies as you get closer to the source, in many cases up the 
the aircraft band or all the way up to 450 MHz (on a different 
receiver). So far my most distant RFI was AC power line RFI 
very strong at my QTH that originates four miles away, It was 
a serious visible arc on a 34 kV subtransmission line (not a local 
13 kV distribution line). The power company was very 
motivated to repair it quickly. 


This recent RFI was very different than anything I've ever 
experienced, I could hear the RFI only on the 160 meter band 
(about 1500- 2000 kHz) It sounded like white noise with no 
audible 60 Hz (or 60 Hz harmonic) component, The only 
way I could locate it was by using the PL-660 S-meter with 
the PL-660 in wideband AM mode. It turned out to be a 
malfunctioning Travellers' Information Station transmitter 
at 1700 kHz. Local hams have an excellent relationship with 
the county Office of Emergency Management that operates the 
transmitter and they turned it off within hours of being notified 
of the problem. 


This is only the second RFI that I've experienced that affects 
only 160 meters. The first one was very intense RFI that 
sounded exactly like classic AC power line RFI but strangely 
it affected only 160 meters and the AM broadcast band. 
It turned out to be a malfunctioning electric fence charger 
one mile away that was stuck continuously on, not pulsing. 
Unfortunately the landowner (an electrician!) was very 
belligerent about refusing to replace his fence charger, but 
some aggressive "social engineering" motivated him to 
change his behavior. 


73 
Frank 
W3LPL 


- Original Message -

From: k...@aol.com 
To: donov...@starpower.net 
Sent: Tuesday, February 16, 2016 10:08:22 AM 
Subject: Tecsun 660 

Hi Frank 

I read your emails on your RFI search. 

Youmay have mentioned it, but what FREQ BAND did you use on the TECSUN in 
your search for the source? 

Was it the AIRCRAFT BAND on FM? 

The reason I ask is that I have a similar radio - that is very similar to 
the radio you used - just made by SONY. 

I wonder if I could use it like you did? I am 99% sure it has the aricraft 
FM band in it. 

Pls let me know when you can. 

Tks 

73 JEFF 

_
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Re: Topband: Antenna Tuners

[Tim Shoppa]

Jim, I mentioned relay cut-in of L's and/or C's at the base of an antenna
to help cover all of 160M. On my tuner web page I mentioned does not show
this recent update I have made at my shack, but I have a relay that shunts
out turns of my 160M coil to help me QSY to top end of 160M phone in
contests.

Another choice that I left out, if you want to QSY all the way between 1800
and 2000 kc with a limited-bandwidth antenna, is relay-cut-in-and-out of
extra length at the top of the antenna. There have been QST articles, as
well as some write-ups on this mailing list, about doing this. The
electrical voltages involved, as well as complications of remotely
controlling relays at the top of an antenna, have made this a non-choice at
my station. I'm very self-satisfied about my relays at the base of my
antenna but the complications of high-voltage relays at the top of an
antenna, is not something I've done myself.

Tim N3QE

On Tue, Feb 16, 2016 at 9:05 AM, Tim Shoppa  wrote:

> My opinions:
>
> All-band antenna tuners make a set of compromises to produce a tuner that
> fits in one box.
>
> They may not be able to handle legal limit on RTTY. Or legal limits CW/SSB
> on other bands, especially the "extreme bands" of 10M and 160M.
>
> They often have 10-turn (or more-turn) roller inductors that make it very
> slow - acutally, downright painful - to QSY between bands.
>
> They usually have very limited choice of tuner topologies, or even worse,
> they don't have the "right topology" for a given band/antenna combination.
>
> If you have the space available in your shack and need a tuner for every
> band, you want to have a tuner optimized for each band in the shack and
> relay selection for tuners. Some pictures of my setup where I have taken
> this to an extreme: http://www.trailing-edge.com/tuners.html
>
> If your only problem is that your 160M antenna is narrow band and doesn't
> cover both 1830kc and 1880kc and 1950kc, your best choice is to cut in (via
> remote relays if you are into automation) some additional L and C at the
> antenna base, as appropriate, to help you QSY between different parts of
> 160M. This will cost you way way less and be far more efficient, than
> buying an all-band tuner in the shack.
>
> Tim N3QE
>
> On Sun, Feb 14, 2016 at 9:30 PM, Jim Murray via Topband <
> topband@contesting.com> wrote:
>
>> Hello all,Would you have any recommendations for antenna tuners?  Have
>> been looking at the automatics, Palstar, Mfj, LDG At-1000Proii etc..  Have
>> been using an old Dentron which doesn't have very close markings on the
>> dials and getting tired of turning and adjusting.  Another option would be
>> another manual such as the At2k with more precise settings. I do quite of
>> bit of band hopping and even on 160 my Inv. L is perfect on 1.830 but
>> doesn't like going very far either up or down, hence the need for a little
>> tuner loss.  The automatics look pretty appealing but would appreciate any
>> opinions from the group.Thanks
>> Jim/k2hn
>> _
>> Topband Reflector Archives - http://www.contesting.com/_topband
>
>
>
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Re: Topband: Antenna Tuners

[Tim Shoppa]

My opinions:

All-band antenna tuners make a set of compromises to produce a tuner that
fits in one box.

They may not be able to handle legal limit on RTTY. Or legal limits CW/SSB
on other bands, especially the "extreme bands" of 10M and 160M.

They often have 10-turn (or more-turn) roller inductors that make it very
slow - acutally, downright painful - to QSY between bands.

They usually have very limited choice of tuner topologies, or even worse,
they don't have the "right topology" for a given band/antenna combination.

If you have the space available in your shack and need a tuner for every
band, you want to have a tuner optimized for each band in the shack and
relay selection for tuners. Some pictures of my setup where I have taken
this to an extreme: http://www.trailing-edge.com/tuners.html

If your only problem is that your 160M antenna is narrow band and doesn't
cover both 1830kc and 1880kc and 1950kc, your best choice is to cut in (via
remote relays if you are into automation) some additional L and C at the
antenna base, as appropriate, to help you QSY between different parts of
160M. This will cost you way way less and be far more efficient, than
buying an all-band tuner in the shack.

Tim N3QE

On Sun, Feb 14, 2016 at 9:30 PM, Jim Murray via Topband <
topband@contesting.com> wrote:

> Hello all,Would you have any recommendations for antenna tuners?  Have
> been looking at the automatics, Palstar, Mfj, LDG At-1000Proii etc..  Have
> been using an old Dentron which doesn't have very close markings on the
> dials and getting tired of turning and adjusting.  Another option would be
> another manual such as the At2k with more precise settings. I do quite of
> bit of band hopping and even on 160 my Inv. L is perfect on 1.830 but
> doesn't like going very far either up or down, hence the need for a little
> tuner loss.  The automatics look pretty appealing but would appreciate any
> opinions from the group.Thanks
> Jim/k2hn
> _
> Topband Reflector Archives - http://www.contesting.com/_topband
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Re: Topband: Antenna Tuners

[Gary Smith]

> I have e-mailed Palstar but, to date, they have not responded. I would 
> love it if someone would come up with a high power, fully weatherized, 
> remote tuner.

I was in a dilemma back in Illinois, I had a Heights 100' aluminium 
fold over tower but insufficient land to put down sufficient radials 
in all but one direction. I had though, excellent results in my condo 
before that, using shortened loop antennas made of copper pipe, 
mounted in an octagon shape hanging  against a wall upstairs. That 
got me to thinking...

I remember reading they were supposed to be 95% transmit-wise, as 
effective as a dipole at the same height. The Q was so high on 80M 
that there was only around 3-4 KHz available at the resonant 
frequency. 

At first, in the condo, I used a vac variable across the feed point 
and adjusted it with the Rx in the room. It was like using a crystal 
radio in that once set, I was essentially rock bound to that 
frequency; at that resonant frequency I could adjust to 1:1 but past 
2 KHz either side and the SWR would be too high. At least I got on 
the air and could call CQ and I made more than a few ATNO that way.

When I moved to the house and had that Heights fold over tower and 
couldn't put down radials for 80, much less 160, I remembered my fix 
at the Condo. This time I built short center fed delta loops for 80 
and 160, mounted them apex up at the top of the tower, just below the 
rotor. It looked somewhat like a K9AY mounted at the top with one 
delta 90 degrees from the other longer delta.

I mounted Vac Variables inside plastic sealed mail boxes mounted to 
the tower at the feed-point, connected them to servos and had the 
servo counterpart in the shack in the basement in a cabinet with 
Groth counters attached to each. The Q was less on these antennas 
because the loops were larger than they were respectively in the 
Condo. Still a high Q but I could get 5-10 KHz of ideal SWR before 
needing to re-adjust the servo (Enough I could effectively run split 
using the Corsair's external VFO). 

With the sensitivity to resistance you get with the servo, it was 
instantly obvious when you were at either end of travel with the Vac 
variable so no chance of damaging the bellow, I could run my legal 
limit amp with zero problems, ever and regardless of where I was on 
the band, I had a 1:1 SWR at the feed-point. 

After a few days of becoming accustomed to the system, it took 
seconds to get me perfectly on frequency. All you needed to do was 
listen and adjust. When you were away from resonance, the radio was 
totally silent except for radio hiss, when you heard the band come 
alive, you were close to resonance, almost ready and could operate. 
Look at the SWR and adjust the final couple degrees of turn and you 
were at 1:1.

It worked perfectly, every time, never failed, always gave me 1:1 at 
the feed-point and considering I had no way to get a really ideal 
antenna up for 80 & 160, this gave me years of excellent operation on 
those bands.

73,

Gary
KA1J

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