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----- Original Message -----
From: capesafari <ft7800@...>
To: QRPops@...
Sent: Thu, 22 Jul 2010 23:50:49 -0700 (PDT)
Subject: [QRPops] Re: 40-meter stealth vertical for balcony

Rhona

You're not alone with the CA restrictions.
(You'll be able to find a lot of info about this topic on the net too)

I can add my experience, working lots of dx, at QRPp levels.
(using mostly cw/digital modes/qrp).

My home setup uses exactly this method, due to CC&Rs. The base of the 33ft pole is on the first story balcony for a little elevation.
I push it up when I operate, and it collapses down and out-of-sight when not used.

Wire thickness depends on your required bandwidth, but it does'nt matter much when you're using an antenna tuner.
I use 26 swg mag wire - which is mostly invisible - 100W no problem.

With this configuration I can work 40 - 10.
The counterpoise situation depends on the design - and in the case of a quaterwave vertical, with elevated radials, you should easily get away with only 2x, sloping down to the ground. It's certainly not ideal and radiation angle may suffer, but it's worth the try to see what you get.
To test the radiation efficiency, I sometimes use wspr for far-field radiation and propagation tests.

Here's an interesting radial write-up :



Also an interesting telescopic pole read here:


Hope your experiments work out great and that you get on-air from home soon!

73,
Deon k6wh


--- In QRPops@..., Rhona Mahony <rmahony@...> wrote:

Hi there gentlepersons,
This month's QST has an article (p. 44) on a 160-meter stealth vertical antenna that made me think that I could easily erect a similar one for 40 meters on my balcony. By telescoping it up only at night, I could evade my condo association's aesthetic restrictions.
Because I won't be carrying this antenna, I am freer in my choice of wire diameter. What diameter do you folks like to use for home verticals and the radial(s)?
My back patio is so narrow that if I use 2 radials, their angle of separation will be less than 90 degrees. Should I just use one radial? It will slope downward from the 12-foot high balcony to whatever I stake it to.
Any tips?
It will be great to have an antenna at home :^)
~~Rhona

--
Rhona Mahony
rmahony@...

------------------------------------

Yahoo! Groups Links

--- In QRPops@..., Rhona Mahony <rmahony@...> wrote:

Hi there gentlepersons,
This month's QST has an article (p. 44) on a 160-meter stealth vertical antenna that made me think that I could easily erect a similar one for 40 meters on my balcony. By telescoping it up only at night, I could evade my condo association's aesthetic restrictions.
Because I won't be carrying this antenna, I am freer in my choice of wire diameter. What diameter do you folks like to use for home verticals and the radial(s)?
My back patio is so narrow that if I use 2 radials, their angle of separation will be less than 90 degrees. Should I just use one radial? It will slope downward from the 12-foot high balcony to whatever I stake it to.
Any tips?
It will be great to have an antenna at home :^)
~~Rhona

--
Rhona Mahony
rmahony@...

--- In QRPops@..., David W Crocker <dwcae@...> wrote:

Here is Martin's response to my request for NEC file for modeling his antenna
using 4NEC2.

Dave W6VYC



----- Forwarded Message ----
From: Martin Hedman <sm0dtk@...>
To: dwcae@...
Sent: Mon, July 12, 2010 8:07:05 PM
Subject: Re: MB Antenna NEC File



Hello Dave! Glad to see that you enjoyed my article in QST and that you have
build a 20 meter version of the antenna. Please see attached nec-file for 21
MHz. I have used a thin insulated wire which is light and strong but puts my
resonance frequency 6 procent in difference when modelling and in real. So when
modelling the included file you will se that it resonance on 22.6 MHz but in
real with my wire used it resonance on 21.2 MHz. So resonance QRG depends on
what kind of wire you use. I have built many versions of the antenna but never
needed some kind of balun. At the moment I have one MH-antenna for 21 MHz and
one for 18 MHz and they works nice with SWR 1,0 and good bandwidth. Good luck
with your project! 73 de Martin



<-----Ursprungligt Meddelande----->

From: David W Crocker [dwcae@...]
Sent: 13/7/2010 4:31:07 AM
To: sm0dtk@...
Cc: neil@...
Subject: MB Antenna NEC File


Martin,

Really enjoyed reading your article in the Mar. issue of QST, also your great
WEBsite. A friend put together a 20M version of your MB Antenna which we got
running but it needs some work as the resonance is too high and the SWR
bandwidth isn't very good. But we did manage to work SK9HQ during the recent
IARU contest with only 10 watts (ICOM703).

Can you send a copy of your NEC file so I can analyze the antenna using 4NEC2.
Also do you think a balun might help?


73, Dave W6VYC

_______________________________________________________________

--- In QRPops@..., Nick Garner <nwgarner@...> wrote:

Howdy Folks,
Ren William Garner was born this past Sunday at 0349. He was 7 lbs. 1 oz
and 19.5 inches. He and mom are doing fine and I'm sleepy. :)

I've uploaded a couple pictures to the group website.

I just saw those pictures of that beam, pretty neat use of the poles.

Also, if anyone has an Android based phone, I've created HamLog for that
platform too. It's still a work in progress though. Let me know if you
want a free copy.

73,
Nick
N3WG

--- On Thu, 7/15/10, Nick Garner wrote:

From: Nick Garner
Subject: [QRPops] N3WG Version 2.0
To: "qrpops"
Date: Thursday, July 15, 2010, 12:36 PM

?

Howdy Folks,
Ren William Garner was born this past Sunday at 0349.? He was 7 lbs. 1 oz and 19.5 inches.? He and mom are doing fine and I'm sleepy. :)

I've uploaded a couple pictures to the group website.

I just saw those pictures of that beam, pretty neat use of the poles.

Also, if anyone has an Android based phone, I've created HamLog for that platform too.? It's still a work in progress though.? Let me know if you want a free copy.

73,
Nick
N3WG

From: Martin Hedman
To: dwcae@...
Sent: Mon, July 12, 2010 8:07:05 PM
Subject: Re: MB Antenna NEC File

_______________________________________________________________

--- In QRPops@..., Rhona Mahony <rmahony@...> wrote:

Hello there,
I am vacationing in Falmouth, Massachusetts, at a Mahony clan rendezvous. Ten of us are in a rented house with various gangs driving down and visiting.
I have put up a NorCal doublet on the elevated back deck, 22 feet per leg of gauge 22 speaker wire. One leg goes to a second story window and the other leg goes through a fork in a tree in the back yard. The center support is a 20-foot telescoping graphite fishing pole. I am using my FT-817 with the Z817 tuner.
I am finding 20 meters so crowded that I can't distinguish a single voice. On 40 meters, I have been hearing people all over the eastern U.S. I haven't yet managed to talk to anybody yet. I need to learn to pounce when an opportunity opens, instead of pausing politely to see whether someone else has been waiting. Pounce, Rhona, pounce!
I am so impressed by your antenna experiments!
Take good care!
~~Rhona, K6RHO
--
Rhona Mahony
rmahony@...

--- In QRPops@..., "w6dlf" <daveflack@...> wrote:

Here's a source for the 17' poles...about what I paid for my from Cabelas a few years ago.

<>

Southern Dave
w6dlf


--- In QRPops@..., "capesafari" <ft7800@> wrote:

Congratulations!!! That looks great!

I like the hub assembly - with the free rotating
mechanism.
Do you keep the spreaders in position by the antenna wire tension, or do you have additional spreader rope to maintain the angles?

Propagation was really favorable to EU during the IARU on 20m.
I managed to work UK with 750mW and sloper on Sat night.
Also the other HQ stations you mentioned were all booming in here.

Did you use an antenna tuner inline?

Also would be curious to know about any performance tests results.
Maybe some f/b and f/s - wspr?

The crappie poles work wonders. I have a few 20ft ones..but need to get myself the 16ft models...(for 20m dimensions)




--- In QRPops@..., "Neil" <neil@> wrote:

Hi gang,

I've been working on a portable version of Martin Hedman's (SM0DTK)
3-element wire beam: The Mini Horse Antenna, QST Mar. 2010.

Although it needs some optimization, Dave (W6VYK) and I got it launched
and operational last Sunday.

Qs with:

KH6LC Keaau, Hi. big antenna farm and station setup for remote
control, check QRZ for details.

AH6NF Honolulu, Hi. Beverly

SK9HQ Karlsborg, Sweden This is a big contest station.

SN0HQ Poland Another big contest station.

The mast was of particular interest to both of us. I've been wondering
how high a mast one could make by stacking surplus 4' fiberglass pole
sections.

Our technique was to plant 2 guy lines roughly 100 degrees apart, then
while keeping the mast leaning evenly against the guys, add sections
from the bottom.

A third guy was tensioned against the other two once we had the altitude
we wanted. We quite easily managed to get the beam up 36 feet. It was a
windless afternoon. Any wind at all would require a second set of guys.

The beam itself is light and could be suspended from a horizontal line
stretched between 2 tall trees. That combination would reduce the weight
enough to make the antenna portable.

I've uploaded photos of the adventure to the photo section.

73, Murf kh6eam

--- In QRPops@..., "capesafari" <ft7800@...> wrote:

Congratulations!!! That looks great!

I like the hub assembly - with the free rotating
mechanism.
Do you keep the spreaders in position by the antenna wire tension, or do you have additional spreader rope to maintain the angles?

Propagation was really favorable to EU during the IARU on 20m.
I managed to work UK with 750mW and sloper on Sat night.
Also the other HQ stations you mentioned were all booming in here.

Did you use an antenna tuner inline?

Also would be curious to know about any performance tests results.
Maybe some f/b and f/s - wspr?

The crappie poles work wonders. I have a few 20ft ones..but need to get myself the 16ft models...(for 20m dimensions)




--- In QRPops@..., "Neil" <neil@> wrote:

Hi gang,

I've been working on a portable version of Martin Hedman's (SM0DTK)
3-element wire beam: The Mini Horse Antenna, QST Mar. 2010.

Although it needs some optimization, Dave (W6VYK) and I got it launched
and operational last Sunday.

Qs with:

KH6LC Keaau, Hi. big antenna farm and station setup for remote
control, check QRZ for details.

AH6NF Honolulu, Hi. Beverly

SK9HQ Karlsborg, Sweden This is a big contest station.

SN0HQ Poland Another big contest station.

The mast was of particular interest to both of us. I've been wondering
how high a mast one could make by stacking surplus 4' fiberglass pole
sections.

Our technique was to plant 2 guy lines roughly 100 degrees apart, then
while keeping the mast leaning evenly against the guys, add sections
from the bottom.

A third guy was tensioned against the other two once we had the altitude
we wanted. We quite easily managed to get the beam up 36 feet. It was a
windless afternoon. Any wind at all would require a second set of guys.

The beam itself is light and could be suspended from a horizontal line
stretched between 2 tall trees. That combination would reduce the weight
enough to make the antenna portable.

I've uploaded photos of the adventure to the photo section.

73, Murf kh6eam

--- In QRPops@..., "Neil" <neil@...> wrote:

Hi gang,

I've been working on a portable version of Martin Hedman's (SM0DTK)
3-element wire beam: The Mini Horse Antenna, QST Mar. 2010.

Although it needs some optimization, Dave (W6VYK) and I got it launched
and operational last Sunday.

Qs with:

KH6LC Keaau, Hi. big antenna farm and station setup for remote
control, check QRZ for details.

AH6NF Honolulu, Hi. Beverly

SK9HQ Karlsborg, Sweden This is a big contest station.

SN0HQ Poland Another big contest station.

The mast was of particular interest to both of us. I've been wondering
how high a mast one could make by stacking surplus 4' fiberglass pole
sections.

Our technique was to plant 2 guy lines roughly 100 degrees apart, then
while keeping the mast leaning evenly against the guys, add sections
from the bottom.

A third guy was tensioned against the other two once we had the altitude
we wanted. We quite easily managed to get the beam up 36 feet. It was a
windless afternoon. Any wind at all would require a second set of guys.

The beam itself is light and could be suspended from a horizontal line
stretched between 2 tall trees. That combination would reduce the weight
enough to make the antenna portable.

I've uploaded photos of the adventure to the photo section.

73, Murf kh6eam

--- On Sun, 6/20/10, Eric wrote:

From: Eric
Subject: [QRPops] Mag Loop Help
To: "qrpops@..."
Date: Sunday, June 20, 2010, 11:05 PM

?

Dear Gang:

Today I made the first tests on my qro mag loop. My goal was for it to be usable from 14 to 21 mhz at 100w. Unfortunately it tunes from 14.800 mhz to 23 mhz.

Here's my question: is there a way to lower the resonance other than increasing the capacitance across the loop? Should i try increasing the feed loop diameter? Here are the design details;

10 ft loop circumference (+joints) 3/4 copper pipe in octagon shape. Feed loop 24" circumference (using 1/5 rule) made from refrigerator tubing about 1/4" dia, feed high capacitor low. Capacitor massive butterfly, measures 30-60 mf

Using the wide-range tuner in my k1 i did hear a number of stations on 20m so i have high hopes!

Thanks

Eric WD6DBM

Sent from my iPhone