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Re: Topband: Fine sigs from George, FO/AA7JV on 80 cw this morning

To: topband@contesting.com
Subject: Re: Topband: Fine sigs from George, FO/AA7JV on 80 cw this morning
From: "GEORGE WALLNER" <aa7jv@atlanticbb.net>
Date: Tue, 04 Apr 2023 15:15:13 -0400
List-post: <mailto:topband@contesting.com>
TobBanders,
I will be on 1827.5 every evening at my SS from 0400 to 0430 (mainly for EU) and then from 1000 to 1200 and again from 1545 to 1615 (my SR), until Apr 8. (Times are +- depending on conditions.)

I normally QSY to 80 at 0430 just after EU SR. Yesterday at my SS conditions on 160 were terrible, but 80 was doing great. Then later, starting around 1000 Z signals on 160 were amazingly strong, both from NA and JA (and Korea) but the lightning crashes were even stronger!

I have a lot of t-storm noise here (and no RX ANT). My noise level goes from -125 dB to -80 dB during the crashes that come every two to three seconds! Please send your call three times to give me chance to "assemble" it. (-80 dB is about equivalent to S9 +5 dB!)

GL and 73,
George,
FO/AA7JV


On Tue, 4 Apr 2023 12:32:20 -0500 David Raymond  wrote:
George has been QRV 160 cw most mornings NA time, sometimes earlier rather than 
later.  He's typically Q5 for the most part but not strong here. . .usually S3 
or S4 peak with QSB to virtually nil.

73. . . Dave, W0FLS

On 4/4/2023 12:09 PM, W3HKK@roadrunner.com wrote:

I looked for George for the 3rd straight day on 160, but no copy.However there 
he was on 3527.5 at 1107z, with a very nice 579 sig andI quickly put him in the 
log. Well after my sunrise hr in Ohio I sawspots for him on 160 cw from several 
West Coast US stations.
Havent heard a dx station on 160 at my SR for at least three days now,but had 
some nice short contacts with assorted VK's on 40 and 20 ssbaround 1130z. 
Pulled 9U5RU out of the noise on 10m ssb shortlythereafter, so some sigs have 
been there for the taking.
The VKs on 20 ssb were 5 S units stronger on the LP when I firstcontacted them, 
but at the end of the qso they were just 2 S unitsstronger LP. Wonder what else 
was coming through that I may havemissed?
        
-----------------------------------------From:topband-request@contesting.comTo: 
topband@contesting.comCc:Sent: Tuesday April 4 2023 12:00:44PMSubject: Topband 
Digest, Vol 244, Issue 4
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Contents of Topband digest..."
 Today's Topics:
 1. Re: High Impedance RX Antennas (Dennis W0JX)  2. Re: High Impedance RX Antennas (Frank W3LPL)  3. Re: High 
Impedance RX Antennas (Tree)  4. Re: High Impedance RX Antennas (Don Moman VE6JY)  5. Re: High Impedance RX Antennas (John 
Kaufmann)  6. Re: [PVRC] 2-element receiving arrays (Dave Cuthbert)  7. Re: High Impedance RX Antennas (Jim Brown)
 ----------------------------------------------------------------------
 Message: 1  Date: Mon, 3 Apr 2023 16:42:37 +0000 (UTC)  From: Dennis W0JX  To: 
"topband@contesting.com"  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:  Content-Type: text/plain; 
charset=UTF-8
 There is an old saying "The enemy of good is perfect."? You will bedriven crazy by chasing down 
every slight variance from the ideal.That being said, it is important to check out the obvious areas whereflaws 
can create big problems. Indeed, the feedline coax, typicallyRG6 CATV line, is a major contributor to array 
performance problems.?The cheap, big box cable is covered with PVC and that stuff hardensand tightens up over the 
years. This allows water to enter the shieldand the water easily migrates for long distances, creating a 
highresistance. Spend the money upfront and buy quality cable that isflooded.  The idea of using cable 
that has a solid copper conductor has merit.But even with that, a bare copper conductor will oxidize over time. 
Ifind myself cleaning these conductors on an annual basis with theeraser end of a pencil (recommended by Lee 
K7TJR).  I have also had F connector
failures on my combiner box and on acommon mode choke. Sometimes the imported female connector centercontact just fails for no reason. The alternative Amphenol connectorsare very expensive at about $8+ each but I am considering replacingthe connectors with these higher grade parts.  Also, the so-called "water-proof" compression connectors are oftennot. The connection must be waterproofed effectively.? Also,condensation from humidity can be a big problem. Here is northeastOhio, the environment is humid for the majority of the year. I havepoured water out of a 75 ohm preamp that was sheltered in a goodenclosure!  These complex phasing arrays are by no means plug and play. Eachinstallation will be unique depending on layout and surroundingobjects. There are three tools necessary to get them and keep themworking:? 1.) a good portable signal source to feed the antennapreamps (I use an Elecraft XG-3 with a home brew impedance transformerat the input);? 2.) a portable transceiver to measure signal out ofthe system at various points (My KX3 does a great job); and anaccurate antenna analyzer to measure impedances and to measurefeedlines and phasing lines for the proper electrical lengths. N6RK isright. There can be considerable difference in RG6 impedance so youneed to check it out.?
 73 Dennis W0JXMilan, OH
 ------------------------------
 Message: 2  Date: Mon, 3 Apr 2023 13:11:27 -0400 (EDT)  From: Frank W3LPL  To: 
topband  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:
 Content-Type: text/plain; charset=utf-8
 Another highly recommended tool is a Time Domain Reflectometer.  Tt easily detects any 
abnormalities in my 8-circle and 4-square  arrays and stacked HF Yagi arrays and switches.
 Other than my hand held antenna analyzer, my hand held TDR is my  most often used and most valuable tool for proving 
that theperformance  of my antennas and feedlines has not changed from prior measurements  and identifying and 
isolating faults before they cause partial or  total failure. A TDR can detect, diagnose and locate feedline 
and  antenna faults from the comfort of your ham shack.
 Affordable TDRs are often available on eBay. Some antenna  analyzers have rudimentary TDR 
capabilities but I've never used  an antenna analyzer with TDR capabilities comparable 
in  performance to a TDR.
 Long before moisture causes coax failure, it causes the impedance  of the coax to change, a 
potentially big problem in a phased array  or stacked Yagis. A TDR easily detects and locates the 
problem  before it causes a failure.
 An antenna analyzer can also detect that moisture has caused  an impedance shift in coax cable. Place a dummy load 
(with the  same impedance as the coax) at one end of the coax cable. Sweep  the antenna analyzer frequency. As you 
do a frequency sweep the  VSWR and impedance should not change. If it does, moisture is  probably eating away 
inside your coax.
 73  Frank  W3LPL
 ----- Original Message -----  From: "Dennis W0JX via Topband"  To: "topband"  Sent: 
Monday, April 3, 2023 4:42:37 PM  Subject: Re: Topband: High Impedance RX Antennas
 There is an old saying "The enemy of good is perfect."? You will bedriven crazy by chasing down 
every slight variance from the ideal.That being said, it is important to check out the obvious areas whereflaws 
can create big problems. Indeed, the feedline coax, typicallyRG6 CATV line, is a major contributor to array 
performance problems.?The cheap, big box cable is covered with PVC and that stuff hardensand tightens up over the 
years. This allows water to enter the shieldand the water easily migrates for long distances, creating a 
highresistance. Spend the money upfront and buy quality cable that isflooded.  The idea of using cable 
that has a solid copper conductor has merit.But even with that, a bare copper conductor will oxidize over time. 
Ifind myself cleaning these conductors on an annual basis with theeraser end of a pencil (recommended by Lee 
K7TJR).  I have also had F connector
failures on my combiner box and on acommon mode choke. Sometimes the imported female connector centercontact just fails for no reason. The alternative Amphenol connectorsare very expensive at about $8+ each but I am considering replacingthe connectors with these higher grade parts.  Also, the so-called "water-proof" compression connectors are oftennot. The connection must be waterproofed effectively.? Also,condensation from humidity can be a big problem. Here is northeastOhio, the environment is humid for the majority of the year. I havepoured water out of a 75 ohm preamp that was sheltered in a goodenclosure!  These complex phasing arrays are by no means plug and play. Eachinstallation will be unique depending on layout and surroundingobjects. There are three tools necessary to get them and keep themworking:? 1.) a good portable signal source to feed the antennapreamps (I use an Elecraft XG-3 with a home brew impedance transformerat the input);? 2.) a portable transceiver to measure signal out ofthe system at various points (My KX3 does a great job); and anaccurate antenna analyzer to measure impedances and to measurefeedlines and phasing lines for the proper electrical lengths. N6RK isright. There can be considerable difference in RG6 impedance so youneed to check it out.?
 73 Dennis W0JXMilan, OH  _________________  Searchable Archives: 
http://www.contesting.com/_topband [1] - TopbandReflector
 ------------------------------
 Message: 3  Date: Mon, 3 Apr 2023 10:20:26 -0700  From: Tree  To: Frank W3LPL  Cc: 
topband  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:
 Content-Type: text/plain; charset="UTF-8"
 I guess most people have some kind of small antenna analyzer that hasa 
TDR  kind of function.
 I have not warmed up to them yet as the results I see seem to be "allover  the 
place". Maybe I just don't know how to use them yet.
 My goto TDR is homebrew - using an analog scope.
 Here is one design pretty similar to what I am using:
 A very simple TDR from W2AEW ? PierpaLab.com   [2] I put a  switch on it to slow down the rep rate 
as an option since some of my  "stuff" is pretty long.
 It works wonderfully to check feedlines and beverages. I have onebeverage  that has transformers and 
feedlines on both ends and I can see the  difference between open/short/terminate on the "far end" 
(which is  physically in the shack).
 73 Tree N6TR
 On Mon, Apr 3, 2023 at 10:11?AM Frank W3LPL  wrote:
 > Another highly recommended tool is a Time Domain Reflectometer.  > Tt easily detects any abnormalities in my 8-circle and 4-square  > arrays and stacked HF Yagi arrays and switches.  >  > Other than my hand held antenna analyzer, my hand held 
TDR is my  > most often used and most valuable tool for proving that theperformance  > of my antennas and feedlines has not changed from priormeasurements  > and identifying and isolating faults before they cause partial or  > total failure. A TDR can 
detect, diagnose and locate feedline and  > antenna faults from the comfort of your ham shack.  >  > Affordable TDRs are often available on eBay. Some antenna  > analyzers have rudimentary TDR capabilities but I've never used  > an antenna 
analyzer with TDR capabilities comparable in  > performance to a TDR.  >  > Long before moisture causes coax failure, it causes the impedance  > of the coax
to change, a potentially big problem in a phased array  > or stacked Yagis. A TDR easily detects and locates the problem  > before it causes a failure.  >  > An antenna analyzer can also detect that moisture has caused  > an impedance shift in coax cable. Place a dummy load (with the  > same impedance as the coax) at one end of the coax cable. Sweep  > the antenna analyzer frequency. As you do a frequency sweep the  > VSWR and impedance should not change. If it does, moisture is  > probably eating away inside your coax.  >  > 73  > Frank  > W3LPL  >  >  >  >  >  > ----- Original Message -----  > From: "Dennis W0JX via Topband"  > To: "topband"  > Sent: Monday, April 3, 2023 4:42:37 PM  > Subject: Re: Topband: High Impedance RX Antennas  >  > There is an old saying "The enemy of good is perfect." You will bedriven  > crazy by chasing down every slight variance from the ideal. Thatbeing  > said, it is important to check out the obvious areas where flawscan create  > big problems. Indeed, the feedline coax, typically RG6 CATV line,is a  > major contributor to array performance problems. The cheap, big boxcable  > is covered with PVC and that stuff hardens and tightens up over theyears.  > This allows water to enter the shield and the water easily migratesfor  > long distances, creating a high resistance. Spend the money upfrontand buy  > quality cable that is flooded.  > The idea of using cable that has a solid copper conductor hasmerit. But  > even with that, a bare copper conductor will oxidize over time. Ifind  > myself cleaning these conductors on an annual basis with the eraserend of  > a pencil (recommended by Lee K7TJR).  > I have also had F connector failures on my combiner box and on acommon  > mode choke. Sometimes the imported female connector center contactjust  > fails for no reason. The alternative Amphenol connectors are veryexpensive  > at about $8+ each but I am considering replacing the connectorswith these  > higher grade parts.  > Also, the so-called "water-proof" compression connectors are oftennot.  > The connection must be waterproofed effectively. Also, condensationfrom  > humidity can be a big problem. Here is northeast Ohio, theenvironment is  > humid for the majority of the year. I have poured water out of a 75ohm  > preamp that was sheltered in a good enclosure!  > These complex phasing arrays are by no means plug and play. Each  > installation will be unique depending on layout and surroundingobjects.  > There are three tools necessary to get them and keep them working:1.) a  > good portable signal source to feed the antenna preamps (I use anElecraft  > XG-3 with a home brew impedance transformer at the input); 2.) aportable  > transceiver to measure signal out of the system at various points(My KX3  > does a great job); and an accurate antenna analyzer to measureimpedances  > and to measure feedlines and phasing lines for the properelectrical  > lengths. N6RK is right. There can be considerable difference in RG6  > impedance so you need to check it out.  >  > 73 Dennis W0JXMilan, OH  > _________________  > Searchable Archives: http://www.contesting.com/_topband [3] -Topband  > Reflector  > _________________  > Searchable Archives: http://www.contesting.com/_topband [4] -Topband  > Reflector  >
 ------------------------------
 Message: 4  Date: Mon, 3 Apr 2023 11:33:10 -0600  From: Don Moman VE6JY  To: "Topband@Contesting. 
Com"  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:
 Content-Type: text/plain; charset="UTF-8"
 A used Tek 1502 TDR is the "gold standard" to me anyway and they canbe  quite cheap at flea markets etc. They are "arm held" and 
selfcontained  portable so ideal for up to 1000' runs and have enough resolutionthat you  can "see" defects that you don't really need to worry about. 
Theadvantage  over some of the VNWA's that have a TDR function, is that the 1502 isreal  time so intermittents can easily be spotted. And it measuresimpedance 
so  you can easily see how long and what Z that unknown roll of fleamarket  coax is!
 I built the scope based TDR from the QST articles years ago, but that  version isn't 
even close to the 1502. I also have a Tek 1503 forchecking  longer runs of control cable etc.
 73 Don  VE6JY
 On Mon, Apr 3, 2023 at 11:21?AM Tree  wrote:
 > I guess most people have some kind of small antenna analyzer thathas a TDR  > kind of function.  >  > I have not warmed up to them yet as the results I see seem to be"all over  > the place". Maybe I just don't know how to use them yet.  >  > My goto TDR is homebrew - using an analog scope.  >  > Here is one design pretty 
similar to what I am using:  >  > A very simple TDR from W2AEW ? PierpaLab.com  >  [5] I put a  > switch on it to slow down the rep rate as an option since some ofmy  > "stuff" is pretty long.  >  > It works wonderfully to check feedlines and beverages. I have onebeverage  > that has transformers and feedlines on both ends and I 
can see the  > difference between open/short/terminate on the "far end" (which is  > physically in the shack).  >  > 73 Tree N6TR  >  > On Mon, Apr 3, 2023 at 10:11?AM Frank W3LPL  > wrote:  >  > > Another highly recommended tool is a Time
Domain Reflectometer.  > > Tt easily detects any abnormalities in my 8-circle and 4-square  > > arrays and stacked HF Yagi arrays and switches.  > >  > > Other than my hand held antenna analyzer, my hand held TDR is my  > > most often used and most valuable tool for proving that theperformance  > > of my antennas and feedlines has not changed from priormeasurements  > > and identifying and isolating faults before they cause partial or  > > total failure. A TDR can detect, diagnose and locate feedline and  > > antenna faults from the comfort of your ham shack.  > >  >
Affordable TDRs are often available on eBay. Some antenna  > > analyzers
have rudimentary TDR capabilities but I've never used  > > an antenna analyzer with TDR capabilities comparable in  > > performance to a TDR.  >
  > > Long before moisture causes coax failure, it causes the impedance  > of the coax to change, a
potentially big problem in a phasedarray  > > or stacked Yagis. A TDR easily detects and locates the problem  > > before it causes a failure.  > >  > > An antenna analyzer can also detect that moisture has caused  > > an impedance shift in coax cable. Place a dummy load (with the  > > same impedance as the coax) at one end of the coax cable. Sweep  > > the antenna analyzer frequency. As you do a frequency sweep the  > > VSWR and impedance should not change. If it does, moisture is  > > probably eating away inside your coax.  > >  > > 73  > > Frank  > > W3LPL  > >  > >  > >  > >  > >  > > ----- Original Message -----  > > From: "Dennis W0JX via Topband"  > > To: "topband"  > > Sent: Monday, April 3, 2023 4:42:37 PM  > > Subject: Re: Topband: High Impedance RX Antennas  > >  > > There is an old saying "The enemy of good is perfect." You willbe  > driven  > > crazy by chasing down every slight variance from the ideal. Thatbeing  > > said, it is important to check out the obvious areas where flawscan  > create  > > big problems. Indeed, the feedline coax, typically RG6 CATV line,is a  > > major contributor to array performance problems. The cheap, bigbox  > cable  > > is covered with PVC and that stuff hardens and tightens up overthe  > years.  > > This allows water to enter the shield and the water easilymigrates for  > > long distances, creating a high resistance. Spend the moneyupfront and  > buy  > > quality cable that is flooded.  > > The idea of using cable that has a solid copper conductor hasmerit. But  > > even with that, a bare copper conductor will oxidize over time. Ifind  > > myself cleaning these conductors on an annual basis with theeraser end  > of  > > a pencil (recommended by Lee K7TJR).  > > I have also had F connector failures on my combiner box and on acommon  > > mode choke. Sometimes the imported female connector centercontact just  > > fails for no reason. The alternative Amphenol connectors are very  > expensive  > > at about $8+ each but I am considering replacing the connectorswith  > these  > > higher grade parts.  > > Also, the so-called "water-proof" compression connectors areoften not.  > > The connection must be waterproofed effectively. Also,condensation from  > > humidity can be a big problem. Here is northeast Ohio, theenvironment is  >
humid for the majority of the year. I have poured water out of a75 ohm  > preamp that was sheltered in a good enclosure!  > > These complex phasing
arrays are by no means plug and play. Each  > > installation will be unique depending on layout and surroundingobjects.  > > There are three tools necessary to get them and keep themworking: 1.) a  > > good portable signal source to feed the antenna preamps (I use an  > Elecraft  > > XG-3 with a home brew impedance transformer at the input); 2.) a  > portable  > > transceiver to measure signal out of the system at various points(My KX3  > > does a great job); and an accurate antenna analyzer to measureimpedances  > > and to measure feedlines and phasing lines for the properelectrical  > > lengths. N6RK is right. There can be considerable difference inRG6  > > impedance so you need to check it out.  > >  > > 73 Dennis W0JXMilan, OH  > > _________________  > > Searchable Archives: http://www.contesting.com/_topband [6] -Topband  > > Reflector  > > _________________  > > Searchable Archives: http://www.contesting.com/_topband [7] -Topband  > > Reflector  > >  > _________________  > Searchable Archives: http://www.contesting.com/_topband [8] -Topband  > Reflector  >
 ------------------------------
 Message: 5  Date: Mon, 3 Apr 2023 14:09:32 -0400  From: "John Kaufmann"  To: "'Topband@Contesting. 
Com'"  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:  Content-Type: text/plain; charset="utf-8"
 Another tool I've found indispensable for setting up andtroubleshooting phased vertical 
RX arrays is a two-port VNA. I use anArray Solutions VNA-2180 (now discontinued) for critical 
measurements.I also have a NanoVNA H4 (https://nanovna.com/) [9] which is a 
very"affordable" VNA that can be used as a portable, handheld, standaloneinstrument 
and that you can take out in the field. In most cases, theNanoVNA H4 is more than good enough.
 There is a learning curve to using a VNA. However, once you learn it,you'll be 
able to make very accurate measurements of delay linelengths, preamplifier gain and 
phase, phase combiner gain and phase.Most VNA's also have a TDR function, although 
it is usually based onfrequency domain measurements that are transformed to the time 
domain.
 I'm running a homebrew RX array and it would have been almostimpossible to get 
it running as well as it is now without a VNA.
 73, John W1FV
 ------------------------------
 Message: 6  Date: Mon, 3 Apr 2023 09:04:26 -1000  From: Dave Cuthbert  To: Frank W3LPL  Cc: 
topband , PVRC  Subject: Re: Topband: [PVRC] 2-element receiving arrays  Message-ID:
 Content-Type: text/plain; charset="UTF-8"
 It seems that padding the element capacitance as needed for equal  capacitance 
would help.
 Dave KH6AQ
 On Thu, Mar 30, 2023 at 4:48?PM Frank W3LPL  wrote:
 > Hi Dave,  >  > Anyone who has experimented with a high impedance antenna such  > as an end fed half wave has experienced the extreme environmental  > influence on the feedpoint impedance of a high impedance feed.  >  > The required spacing to trees and buildings is very difficult topredict  > with any confidence. The impedance of a high impedance element  > -- and hence the amount of voltag if feeds into the 
preamp --  > is heavily influenced by its immediate environment.  >  > If all of the high impedance verticals in an array do not producethe  > same voltages from the signals received by the array, the pattern  > of the array and especially its nulls are significantly degraded.  >  > 73  > Frank  > 
W3LPL  >  >  >  >  >  >  >  > From: "K3ZJ David Siddall"  > To: "Frank W3LPL"  > Cc: "topband" , "PVRC" ,  > "Pete N4ZR N4ZR"  > Sent: Friday, March 31, 2023 12:34:28 AM  > Subject:
Re: [PVRC] Topband: 2-element receiving arrays  >  > Frank,  > " wrt to-negative effects of nearby trees and buildings." for high  > impedance verticals:  >  > Is there any data measuring how much loss if placed in the woods?Minimum  > distance from a tree to minimize the loss? Are their other effectstoo,  > such as less directionality?  >  > 73, Dave K3ZJ  >  >  >  > On Thu, Mar 30, 2023 at 1:38 PM Frank W3LPL < [ mailto:  > donovanf@starpower.net | donovanf@starpower.net ] > wrote:  >  >  > Hi Pete,  >  > For a monoband receiving array, you might consider using lowimpedance  > resonant verticals rather than high impedance verticals.  >  > The primary advantages of high impedance verticals are  > - very short verticals (but taller verticals produce strongersignals)  > - multi-band operation  > - no radials  >  > The primary disadvantages are  > - reliability issues with outdoor electronics  > - lightning susceptibility of outdoor electronics  > - higher cost  > - much lower signal levels  > - extreme care required to suppress common mode signals (buriedfeedlines  > are highly recommended)  > - negative effects of nearby trees and buildings.  >  > The primary advantages of low impedance verticals are  > - much stronger signal levels  > - much less criticality of common mode signal suppression,  > - much lower cost  > - much higher reliability  > - immunity to lightning damage  > - much less affected by nearby trees and buildings  >  > The primary disadvantages are  > - taller verticals (typically about 24 feet)  > - radials (they can be very short if many radials are used)  > - mono band operation (switchable matching networks can be used for  > multi-band operation).  >  > I highly recommend the DX Engineering Receiving Antenna PhasingSystem.  > Its expensive but well worth the investment especially for a smallarray.  >  > [ https://www.dxengineering.com/parts/dxe-ncc-2 [10] |  > https://www.dxengineering.com/parts/dxe-ncc-2 [11] ]  >  > If you have 120 feet for a three element array, the YCCC array is agreat  > choice  > It can use high impedance or low impedance verticals  > Unfortunately its no longer available from DX Engineering  > The nine element YCCC array uses only three active elements at anytime,  > so its really a three element array switchable in many directions.  >  > [  >https://static.dxengineering.com/global/images/instructions/dxe-yccc-switch.pdf?_gl=1*1cv0fc9*_ga*MjEyMDA1Nzc3MS4xNjUyMzAyMjc0*_ga_NZB590FMHY*MTY4MDE5NTk1OC40My4xLjE2ODAxOTYwNTYuNTAuMC4w  /> > |  >https://static.dxengineering.com/global/images/instructions/dxe-yccc-switch.pdf?_gl=1*1cv0fc9*_ga*MjEyMDA1Nzc3MS4xNjUyMzAyMjc0*_ga_NZB590FMHY*MTY4MDE5NTk1OC40My4xLjE2ODAxOTYwNTYuNTAuMC4w  /> > ]  >  > [ https://www.youtube.com/watch?v=dl-crM5Kb6A [12] |  > https://www.youtube.com/watch?v=dl-crM5Kb6A [13] ]  >  > [ https://www.youtube.com/watch?v=lVW1CmrzP7c [14] |  > https://www.youtube.com/watch?v=lVW1CmrzP7c [15] ]  >  > A two element array occupies only 60 feet or even a little less.  >  > 73  > Frank  > W3LPL  >  >  > ----- Original Message -----  > From: "Pete N4ZR N4ZR" < [ mailto:pete.n4zr@gmail.com |  > pete.n4zr@gmail.com ] >  > To: "topband" < [ mailto:Topband@contesting.com |Topband@contesting.com  > ] >  > Sent: Thursday, March 30, 2023 12:54:30 PM  > Subject: Topband: 2-element receiving arrays  >  > Thinking ahead to next winter on 160, I'm interested in replacingmy  > K9AY Loop with a 2-vertical phased array. I'd like to homebrew the  > antennas and just buy or build the remote control unit for theshack.  > I'm looking for sources of components (antenna-located preamps andan  > in-shack controller), and would prefer not to completely homebrewthem,  > but the prices at the usual suspects are awfully high. Any ideas?  >  > I have pretty reasonably-priced access to 25 and 31-foot fiberglass  > poles (used for wind-socks by model airplane enthusiasts). I'mthinking  > that one relatively low-cost approach might be to attach, say, #14wire  > to the poles, with preamps at the base, but wonder if there is a  > downside to using such small-diameter antenna elements rather than1 or  > 1.5 inch tubing? Alternatively, are clones of the DX Engineering 8'  > short verticals with preamps a good alternative?  >  > --  > 73, Pete N4ZR  > _________________  > Searchable Archives: [ http://www.contesting.com/_topband [16] |  > http://www.contesting.com/_topband [17] ] - Topband Reflector  > ______________________________________________________________  > PVRC mailing list  > Home: [ http://mailman.qth.net/mailman/listinfo/pvrc [18] |  > http://mailman.qth.net/mailman/listinfo/pvrc [19] ]  > Help: [ http://mailman.qth.net/mmfaq.htm [20] |  > http://mailman.qth.net/mmfaq.htm [21] ]  > Post: mailto: [ mailto:PVRC@mailman.qth.net | PVRC@mailman.qth.net]  > Message delivered to [ mailto:davek3zj@gmail.com |davek3zj@gmail.com ]  >  > This list hosted by: [ http://www.qsl.net/ [22] |http://www.qsl.net [23] ]  > Please help support this email list: [http://www.qsl.net/donate.html [24] |  > http://www.qsl.net/donate.html [25] ]  >  >  >  > _________________  > Searchable Archives: http://www.contesting.com/_topband [26] -Topband  > Reflector  >
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 Message: 7  Date: Mon, 3 Apr 2023 12:18:02 -0700  From: Jim Brown  To: 
topband@contesting.com  Subject: Re: Topband: High Impedance RX Antennas  Message-ID:
 Content-Type: text/plain; charset=UTF-8; format=flowed
 On 4/3/2023 10:20 AM, Tree wrote:  > I guess most people have some kind of small antenna 
analyzer thathas a TDR  > kind of function.
 In my professional life in pro audio, I started doing Time Domain  Spectrometry in 1982, so I have a pretty good handle on how it 
works.  There is a mathematical relationship between the frequency responseof a  system and its time response -- one is the inverse of the 
other. The  Fourier Transform of the time response yields the frequency response,  and the Inverse Fourier of the frequency response yields the 
time  response. Modern antenna analyzers produce a swept frequencyresponse,  and associated software running on the computer does the 
InverseFourier  Transform of a sweep to produce the TDR.
 For more than 10 years, the best of the low cost Vector Network  Analyzers has been the VNWA3SE, built and sold as a finished 
andtested  unit, by SDR Kits, run by hams in UK. The unit, its firmware, and  associated software, was designed by DG8SAQ, 
an EE prof. Support from  both DG8SAQ and SDR Kits is excellent -- both read and respond totheir  support email reflector. 
Current cost with shipping is about $560  (depending on currency).
https://www.sdr-kits.net/introducing-DG8SAQ-VNWA3  />  Greatest precision (ability to see small things) is 
provided by asweep  over a very wide frequency range. I usually sweep from 50-500 MHz.Once  the sweep is 
done, the TDR is simply a few more button pushes in the  menu system.
 73, Jim K9YC
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 ------------------------------
 End of Topband Digest, Vol 244, Issue 
4  ***************************************
Links:------[1] http://www.contesting.com/_topband[2] 
https://pierpalab.com/2022/04/30/a-very-simple-tdr-from-w2aew/%3E[3] 
http://www.contesting.com/_topband[4] http://www.contesting.com/_topband[5] 
https://pierpalab.com/2022/04/30/a-very-simple-tdr-from-w2aew/%3E[6] 
http://www.contesting.com/_topband[7] http://www.contesting.com/_topband[8] 
http://www.contesting.com/_topband[9] https://nanovna.com/)[10] 
https://www.dxengineering.com/parts/dxe-ncc-2[11] 
https://www.dxengineering.com/parts/dxe-ncc-2[12] 
https://www.youtube.com/watch?v=dl-crM5Kb6A[13] 
https://www.youtube.com/watch?v=dl-crM5Kb6A[14] 
https://www.youtube.com/watch?v=lVW1CmrzP7c[15] 
https://www.youtube.com/watch?v=lVW1CmrzP7c[16] 
http://www.contesting.com/_topband[17] http://www.contesting.com/_topband[18] 
http://mailman.qth.net/mailman/listinfo/pvrc[19] 
http://mailman.qth.net/mailman/listinfo/pvrc[20]
http://mailman.qth.net/mmfaq.htm[21] http://mailman.qth.net/mmfaq.htm[22] http://www.qsl.net/[23] http://www.qsl.net[24] http://www.qsl.net/donate.html[25] http://www.qsl.net/donate.html[26] http://www.contesting.com/_topband
_________________Searchable Archives: http://www.contesting.com/_topband - 
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