Choke balun
 

On Sat, 6 Jan 2007 11:31:45 -0500, "Jimmie D"
wrote:

The ones who were doing it arent around anymore

Hi Jimmie,

Is it possible you had the key down when they last tried lowering it?

73's
Richard Clark, KB7QHC

Choke balun
 

Jimmie D wrote:
Yeah I thought about this but was trying to stay away from raising and
lowering the antenna. I used to have the antenna on a pulley but found that
sometimes the neighbor kids would lower it for me. The ones who were doing
it arent around anymore so I guess its safe to put it back up now.

Them "not being around anymore" could mean any number
of things. :-)
--
73, Cecil http://www.w5dxp.com

Choke balun
 

"Richard Clark" wrote in message
...
On Sat, 6 Jan 2007 11:31:45 -0500, "Jimmie D"
wrote:

The ones who were doing it arent around anymore

Hi Jimmie,

Is it possible you had the key down when they last tried lowering it?

73's
Richard Clark, KB7QHC

No, they were reallly good kids over all, they didnt get into half as much
as I did when they were my age. At least I dont think they ever fished with
pipe bombs. They also kept my grass cut while I was away for a really
reasonable price.

Interesting 144 foot Dipole
 

Cecil Moore wrote:

Jim Kelley wrote:

Can you describe the balun you used?


When one feeds the antenna system at a current maximum
point, the balun is non-critical. I am presently using
ten turns of RG-400 on an FT-240-61 toroid with no
measurable common mode current on an MFJ-853. As you
know, the stress on the balun is reduced when the
resonant current maximum point is located at the
output of the balun-choke. That's another bonus for
the matching system that I use.

Hi Cecil,

I guess what I meant to ask was, how do you interface ladder line with
your IC756 output connector?

Thanks,

Jim, AC6XG

(And hello to fellow SCHS alum, Jeff Herman)

Interesting 144 foot Dipole
 

Jim Kelley wrote:
I guess what I meant to ask was, how do you interface ladder line with
your IC756 output connector?

I've got an SG-500 between the IC756 and the antenna.
Coax out of the SG-500 goes to a 1:1 balun-choke and
then to the ladder-line.
--
73, Cecil http://www.w5dxp.com

Choke balun
 

Jeffrey Herman wrote:
Cecil Moore wrote:
When one feeds the antenna system at a current maximum
point, the balun is non-critical. I am presently using
ten turns of RG-400 on an FT-240-61 toroid with no

Hi Cecil,
It seems like it's been a decade since we debated on RRAP. I hope all is
well with you.
.... and here *I* am again. Anybody heard from Gary Coffman?

For a balun, I'm considering N4UJW's "Ugly Balun"
(see http://www.hamuniverse.com/balun.html).
UJW leaves the diameter of the coil form to the reader,

So, my question is about choke baluns too. I just put up a shiny new GAP
Eagle (yah, yah, I know short multiband verticals are snake oil, if I
had a big lot I might do something different.) They recommended a small
coax coil balun, but when I did that (as compared to just checking the
resonance at the little tail coming out of the antenna) the 20M
resonance went to pieces-- previously it had been 1:2 SWR (compared to
50 ohms) throughout the band, it went to 1:3 (but pretty flat)
everywhere. I ended up just using a ferrite-bead choke balun I had
around, and everything was fine. So, does anybody here have any idea
why the coax coil choke and the ferrite bead choke would have been so
different?

Rich, K6RFM

Choke balun
 

On Tue, 09 Jan 2007 23:47:41 -0800, Rich McAllister K6RFM
wrote:

So, does anybody here have any idea
why the coax coil choke and the ferrite bead choke would have been so
different?

Hi Rich,

I have been using a GAP Eagle for years, and it resonates in every
band as advertised (which is not to be mistaken for works miracles in
every band).

It comes with its own ferrite choke (aka 1:1 BalUn) on the pigtail
lead coming out of the bottom. Over the years and with wind, that has
chipped and broken, but replacing it returned the original
performance. By the way, I did have it elevated 10 feet up - this
makes a difference.

73's
Richard Clark, KB7QHC

Choke balun
 

Rich McAllister K6RFM wrote:
So, does anybody here have any idea
why the coax coil choke and the ferrite bead choke would have been so
different?

Was the coax choke single layer or bunched?
How many turns on what diameter? Here's some
measured data:

http://www.k1ttt.net/technote/airbalun.html

Note the narrow bandwidth of the coax coils
Vs the broad bandwidth of the beads.
--
73, Cecil http://www.w5dxp.com

Choke balun
 

Rich McAllister K6RFM wrote:
So, my question is about choke baluns too.

Here's some good technical information on the
various ferrite materials.

http://www.amidoncorp.com/aai_ferritecores.htm
--
73, Cecil http://www.w5dxp.com

Choke balun
 

Cecil Moore wrote:
Rich McAllister K6RFM wrote:
So, does anybody here have any idea why the coax coil choke and the
ferrite bead choke would have been so different?

Was the coax choke single layer or bunched?
How many turns on what diameter?

Just 4 turns about 6" diameter, bunched up and secured with cable ties
as GAP recommended. Hard to believe there was some kind of narrow-band
resonance that just hit 20M, but I guess stranger things have happened.

Rich