Date   

Random Wire Antenna

Darryl J Kelly
 

I have a 70' end fed wire, 10' at feed end up to a tree at 25', last
20' sloping down, 9:1 unun, 50' of coax on ground, 26' counterpoise
sloping down to and on ground. High SWR 6.7 at 6 meters, most much
lower, high impedance 110, also most much lower. Tuneable on 80
through 6 meters with LDG AT-200 Pro II tuner. I have very good SWR
measurements with different random lengths from 40' to 115'. Just my
experience.
Darryl, KK5IB


Re: The mysteries of tuning a random wire

J.K. Wright
 

You might enjoy this link:

Jerry, NK2C

On Sun, Jun 14, 2020, 12:24 PM Dave W0DCX <cwqrp73@...> wrote:
Jim, thanks for your mentoring.  I am going to follow up and report back with the specific data you requested.  What I am trying to do here is explore the electromagnetic behavior of random wires AND try to optimize performance of the simplest and most efficient designs possible.  So my goals are both academic and pragmatic.  My usually practice is to use a 9:1 unun to feed my random wires.  In combination with the KX2 ATU this makes almost all things possible.  But I wanted to reduce/simplify/streamline as much as possible the electronics involved so I am now going back and experimenting with random wires fed directly by the transceiver without the unun.  The idea, perhaps an erroneous one, is maximize power efficiency in the output circuit by providing a direct connection between the XCVR ATU and the antenna - no unun and no coax.  Trying to get as much oomph from my QRP output as possible.  I might be on the right track if. and that is a big if, I can get the antenna and the counterpoise perfectly optimized for a specific frequency.  Is there any validity to my thinking? Or am I just spinning my wheels and worrying too much about a little power loss.

So, in answer to some of your cogent questions; 1) no feedline - antenna and counterpoise connect directly to XCVR ATU, 2) far end of antenna is at about 35 feet, 3) counterpoise is single conductor , 4) counterpoise runs down through floor and runs along top of basement foundation wall so about 18 inches above ground, and 5) counterpoise is only 17 feet long.  Okay, that seems rather short for a 40m band counterpoise so I will try lengthening that for 40m or better yet add a second counterpoise of 33 feet.
Thanks,
Dave W0DCX


Re: The mysteries of tuning a random wire

Dave W0DCX
 

Jim, thanks for your mentoring.  I am going to follow up and report back with the specific data you requested.  What I am trying to do here is explore the electromagnetic behavior of random wires AND try to optimize performance of the simplest and most efficient designs possible.  So my goals are both academic and pragmatic.  My usually practice is to use a 9:1 unun to feed my random wires.  In combination with the KX2 ATU this makes almost all things possible.  But I wanted to reduce/simplify/streamline as much as possible the electronics involved so I am now going back and experimenting with random wires fed directly by the transceiver without the unun.  The idea, perhaps an erroneous one, is maximize power efficiency in the output circuit by providing a direct connection between the XCVR ATU and the antenna - no unun and no coax.  Trying to get as much oomph from my QRP output as possible.  I might be on the right track if. and that is a big if, I can get the antenna and the counterpoise perfectly optimized for a specific frequency.  Is there any validity to my thinking? Or am I just spinning my wheels and worrying too much about a little power loss.

So, in answer to some of your cogent questions; 1) no feedline - antenna and counterpoise connect directly to XCVR ATU, 2) far end of antenna is at about 35 feet, 3) counterpoise is single conductor , 4) counterpoise runs down through floor and runs along top of basement foundation wall so about 18 inches above ground, and 5) counterpoise is only 17 feet long.  Okay, that seems rather short for a 40m band counterpoise so I will try lengthening that for 40m or better yet add a second counterpoise of 33 feet.
Thanks,
Dave W0DCX


Re: The mysteries of tuning a random wire

Jim, N5IB
 

Go a step further with your Nano.

After getting the swr data, also get the impedance information (R +/- jX). You may find one case of high swr involves a fairly low impedance, while another case is associated with a fairly high impedance. Some tuners are happier matching one or the other. depending on their design. Especially if there is a large reactive (X) component of the impedance.

Report back what you find, and also report:
is there a feedline involved, or do the counterpoise and antenna both terminate at the rig?
how high is the far end of the antenna?
is the counterpoise a single conductor? how long?
how is the counterpoise deployed? on the ground? elevated? if so, how high?

N5IB


The mysteries of tuning a random wire

Dave W0DCX
 

Here is another antenna tuning conundrum.  This morning I hoisted up a 72-foot random wire (and deployed a counterpoise).  My calculations suggested it should tune great on 30 meters (almost exactly 3/4 wavelength) but poorly on 40 or 20 meters (close to 1/2 wave multiples).  Here is what I found in terms of SWR of the untuned antenna as determined by my NanoVNA and what I observed when I tried to achieve a good SWR match with my KX2 automatic antenna tuner.

30 meters - VNA SWR = 2.3; KX2 can tune to SWR = 1.0  : NICE!
20 meters - VNA SWR = 13.17; KX2 can tune to SWR = 1.0 : NICE BUT SURPRISED!
40 meters - VNA SWR = 4.4; KX2 can only tune to SWR = 4.4 : TOTALLY BAFFLED - WHY?

Any insights?
Dave W0DCX


Re: Question About The 4 States Antenna Tuner

David Wilcox
 

Don’t forget the screen door of your slider out to the deck.  Make sure the screen is metal, but then again the metal frame itself will work fine too.  You get a higher score if the slider looks out on a golf course.

David J. Wilcox K8WPE’s iPad

On Jun 12, 2020, at 4:55 PM, Frank Perkins <N6CES.r@...> wrote:


Hi Dave, good thinking on the rain gutter antenna. Have scraped off a little paint and clipped to a downspout on one in the past.
After all, anything metal is an antenna.
An old couch spring could become a circular polerised yagi for 3 GigaHertz!!
Frank N6CES
After

On Fri, Jun 12, 2020, 1:14 PM Dave W0DCX <cwqrp73@...> wrote:
Thank you, Jeff, for that link.  I think I have become spoiled with the marvelous internal tuner in my KX2 that will tune just about anything including the proverbial rain gutter.
Dave


Upcoming Event: 4SQRP Second Sunday Sprint - Sun, 06/14/2020 19:00-21:00 #cal-reminder

main@4SQRP.groups.io Calendar <main@...>
 

Reminder: 4SQRP Second Sunday Sprint

When: Sunday, 14 June 2020, 19:00 to 21:00, (GMT-05:00) America/Chicago

View Event

Organizer: John Lonigro

Description: 4SQRP Second Sunday Sprint. See http://www.4sqrp.com/4sqrpOnTheAir.php for details.


Re: Question About The 4 States Antenna Tuner

Frank Perkins
 

Hi Dave, good thinking on the rain gutter antenna. Have scraped off a little paint and clipped to a downspout on one in the past.
After all, anything metal is an antenna.
An old couch spring could become a circular polerised yagi for 3 GigaHertz!!
Frank N6CES
After


On Fri, Jun 12, 2020, 1:14 PM Dave W0DCX <cwqrp73@...> wrote:
Thank you, Jeff, for that link.  I think I have become spoiled with the marvelous internal tuner in my KX2 that will tune just about anything including the proverbial rain gutter.
Dave


Re: Question About The 4 States Antenna Tuner

Dave W0DCX
 

Thank you, Jeff, for that link.  I think I have become spoiled with the marvelous internal tuner in my KX2 that will tune just about anything including the proverbial rain gutter.
Dave


SSCPO Sales have resumed!

nm0s_qrp
 

After waiting 3 months for parts on a slow boat from China, SSCPO sales have resumed!

73 Dave


Re: 40 and 80 Meter Net Report

Johnny AC0BQ
 

Gm Chas
I must say, your signal last night may have been the best that I have heard from you.
I actually copied more than ur call and my signal report!!
Good job.
72
Johnny ACØBQ 

On Wed, Jun 10, 2020 at 9:30 PM <w2sh@...> wrote:
My 40m QNI was a nice piece of cake both ways.   On 80m I listened for several minutes to a number of signals whose strength was 4 to 5.  However readability was zero because of nearby thunderstorm activity.  The QRN was deafening, so I disconnected the antennas, grounded them and pulled the AC power plug.. 

The storms will abate tomorrow afternoon and I will QNI the NEQRP net on 3.566 mHz Thursdays at 2030 ET.

If you want to find out how a net is properly conducted, listen, or better yet QNI;  NCS Chuck, K1CL, is an impeccable maestro.

72,

Charles (aka Chas), W2SH


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of Johnny AC0BQ <jomatlock@...>
Sent: Wednesday, June 10, 2020 22:01
To: 4sqrpio <4SQRP@groups.io>
Subject: [4SQRP] 40 and 80 Meter Net Report
 
Ge Group 
Not a bad net for tough band conditions. 

Check in's were: 
40 Meters
KW4JS
K4EQ
N4ELM 
W2SH 

80 Meters was a little better, believe it not! 
Check in's were:
N0YJ
KL7IXI 
K4EQ Double 
N4ELM Double 
WG5F 
K5TD (Almost) lost him on the return. 

Thanks everyone, stay cool and Safe! 
72 
Johnny AC0BQ


--
Charles Moizeau, W2SH

--
Check out the 4SQRP website at 4sqrp.com


Re: Question About The 4 States Antenna Tuner

Jeff Logullo N0̸MII
 

Dave,

Glad you have solved the mystery of your tuner's behavior!

Here's an article that you -- and others -- might enjoy: 

   Getting the Most Out of Your T-Network Antenna Tuner, by Andrew Griffith W4ULD (from QST January 1995)

"To achieve the highest possible efficiency at a given impedance transformation, tune the network with the highest output capacitance that allows a match."

The section on the last page, "For Tapped-Inductor Tuners" summarizes the process to follow to accomplish the above.

Jeff N0MII

On Jun 6, 2020, at 5:19 PM, Dave W0DCX <cwqrp73@...> wrote:

Well well well.  This has been pretty interesting, somewhat humiliating, and rather humorous.  I followed Jim's directive and, at least with the dummy load in place, the Tuner at last seems to be behaving as one might expect. So maybe I did assemble it correctly!  Who would have thought!  In the final step, as per Jim's advice, I replaced my NanoVNA with my transceiver set on 40-meters at 1 watt and obtained the same LED pattern on the Tuner.  Interestingly, when I switched to 20-meters at first it seemed not to work well.  But I was assuming there was an incremental pattern of tuning to be expected when adjusting the inductor.  I had previously assumed that I could "bracket" the inductor settings to more quickly figure out the best tuning, but I guess not.  I think one has to try each and every inductor setting more methodically.  Lo and behold I found that 20-meters gave me the green light when I had the inductor at the B position, Cap-L at 10 and Cap-R at 0.  B is the next to highest setting of A which worked well for 40-meters.  Lesson learned is that I need to be completely empirical when trying to adjust the tuner for the best match and not assume any patterns will emerge.  But the big question now is how will this all work with an actual antenna instead of a dummy load?  I was flummoxed when I first tried it on my AX1 vertical whip, but maybe now that I understand the tuning process better I can get it to work with that and other antennas too.
Thanks!
Dave W0DCX


--
Jeff N0̷MII


Re: 40 and 80 Meter Net Report

n4mj
 

GE Johnny.  I listened for the net but didn't hear anyone.  Band was unusually noisy for the chosen frequency.
Still no 80m capability so that was out.

Looks like it will be a couple of months before I get the tower up and new wire antennas higher than 18'. hi hi

Will try again next week.

73 de n4mj


 
PLEASE REMOVE all email addresses before you send it on and use BCC option when forwarding"
  Thank you! 



On Wednesday, June 10, 2020, 09:02:03 PM CDT, Johnny AC0BQ <jomatlock@...> wrote:


Ge Group 
Not a bad net for tough band conditions. 

Check in's were: 
40 Meters
KW4JS
K4EQ
N4ELM 
W2SH 

80 Meters was a little better, believe it not! 
Check in's were:
N0YJ
KL7IXI 
K4EQ Double 
N4ELM Double 
WG5F 
K5TD (Almost) lost him on the return. 

Thanks everyone, stay cool and Safe! 
72 
Johnny AC0BQ


Re: 40 and 80 Meter Net Report

w2sh@...
 

My 40m QNI was a nice piece of cake both ways.   On 80m I listened for several minutes to a number of signals whose strength was 4 to 5.  However readability was zero because of nearby thunderstorm activity.  The QRN was deafening, so I disconnected the antennas, grounded them and pulled the AC power plug.. 

The storms will abate tomorrow afternoon and I will QNI the NEQRP net on 3.566 mHz Thursdays at 2030 ET.

If you want to find out how a net is properly conducted, listen, or better yet QNI;  NCS Chuck, K1CL, is an impeccable maestro.

72,

Charles (aka Chas), W2SH


From: main@4SQRP.groups.io <main@4SQRP.groups.io> on behalf of Johnny AC0BQ <jomatlock@...>
Sent: Wednesday, June 10, 2020 22:01
To: 4sqrpio <4SQRP@groups.io>
Subject: [4SQRP] 40 and 80 Meter Net Report
 
Ge Group 
Not a bad net for tough band conditions. 

Check in's were: 
40 Meters
KW4JS
K4EQ
N4ELM 
W2SH 

80 Meters was a little better, believe it not! 
Check in's were:
N0YJ
KL7IXI 
K4EQ Double 
N4ELM Double 
WG5F 
K5TD (Almost) lost him on the return. 

Thanks everyone, stay cool and Safe! 
72 
Johnny AC0BQ


--
Charles Moizeau, W2SH


Delta Romeo Mike net

Robert
 

Good evening 

Tonight's check in's

WG5F ED
KU5M JOE
AC0BQ JOHNNY
N4ELM  BILL ALL 3  NETS GREAT JOB
N0TGR DICK
N0TU MIKE

THANKS AGAIN
73'S
BERT
N0YJ


40 and 80 Meter Net Report

Johnny AC0BQ
 

Ge Group 
Not a bad net for tough band conditions. 

Check in's were: 
40 Meters
KW4JS
K4EQ
N4ELM 
W2SH 

80 Meters was a little better, believe it not! 
Check in's were:
N0YJ
KL7IXI 
K4EQ Double 
N4ELM Double 
WG5F 
K5TD (Almost) lost him on the return. 

Thanks everyone, stay cool and Safe! 
72 
Johnny AC0BQ


Wednesday Evening 40 and 80 meter Nets - Wed, 06/10/2020 #cal-notice

main@4SQRP.groups.io Calendar <noreply@...>
 

Wednesday Evening 40 and 80 meter Nets

When:
Wednesday, 10 June 2020
20:00 to 21:00
(GMT-05:00) America/Chicago

Where:
40 and 80 Meters

Organizer:
jomatlock@...

Description:
The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS is WQ5RP/ACØBQ 

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 



The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operator is Johnny ACØBQ 

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.


Upcoming Event: Wednesday Evening 40 and 80 meter Nets - Wed, 06/10/2020 20:00-21:00 #cal-reminder

main@4SQRP.groups.io Calendar <main@...>
 

Reminder: Wednesday Evening 40 and 80 meter Nets

When: Wednesday, 10 June 2020, 20:00 to 21:00, (GMT-05:00) America/Chicago

Where:40 and 80 Meters

View Event

Organizer: jomatlock@...

Description: The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS is WQ5RP/ACØBQ 

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 



The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operator is Johnny ACØBQ 

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.


Upcoming Event: Wednesday Evening 40 and 80 meter Nets - Wed, 06/10/2020 20:00-21:00 #cal-reminder

main@4SQRP.groups.io Calendar <main@...>
 

Reminder: Wednesday Evening 40 and 80 meter Nets

When: Wednesday, 10 June 2020, 20:00 to 21:00, (GMT-05:00) America/Chicago

Where:40 and 80 Meters

View Event

Organizer: jomatlock@...

Description: The 40 Meter Net will be at 8:00 pm central time  on 7.122 +-. QRM
NCS is WQ5RP/ACØBQ 

Wednesday evening 80 Meter CW Net. will be at  (8:30PM Central Time Wednesday). 



The 80 meter net will be called on 3.564 MHz +/- QRM.
Net control operator is Johnny ACØBQ 

* NEW *  Wednesday evening DMR Voice Net will be at (Thursday) 0300 UTC (9:00PM Central Time Wednesday/)
Four States QRP has a Brandmeister DMR Talk Group (TG31654). Join us to discuss QRP, ask questions, or just ragchew. The Wednesday net is a directed net  but any other time you may use the Talk Group to chat with other QRPers.
Net Control operator is Bert NØYJ.


W0RW@Ice Station Zebra, on 14061, 10 June, 1700Z

w0rw
 

Advanced  Notice...   W0RW ...

I will be operating from Ice Station Zebra, <http://tinyurl.com/zgss4yu>.

There is an inch of snow there now.

Date:    10 June, 2020.
Freq:   14061 kHz +/- 1.

Time:  1700z, (1pm EDT ).

 

I will be using my   PRC319 "Lite", 

It looks like a real PRC319 but It has a  '1 Watter'  inside,

 all sealed in a water tight, goat proof case.

 

 You can see the story of this rig in the

NAQCC June Newsletter newsletter article, p.8 :
http://www.naqcc.info/newsletter_current_lores.pdf


You can read more about Pedestrian Mobile operations in

CQ Magazine, Sept. 2018.

 

Paul w0rw

@ Ice Station Zebra, Colorado