I am interested in the QEX article. If anyone would be willing
to mail me a copy (or even e-mail a scan of it) I would be glad
to pay for it.
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Joe Reisert
Sent: Thursday, January 30, 2003 10:17 AM
To: Jim Harris; Dinsterdog@aol.com; towertalk@contesting.com
Subject: Re: [TowerTalk] MA5V Vertical question
Paul and Jim,
The Cushcraft MA5V was designed by K1BQT, Rick Littlefield and he
calls it
an "Off Center Fed Dipole). In the Jan/Feb 2002 issue of QEX,
page 54, is a
complete technical write up on same.
I believe the coax in the isolator is RG58 (not RG59). Beware,
this is a
low power antenna and is only specified to handle 250 Watts PEP
SSB!
73,
Joe, W1JR
At 07:35 PM 1/28/2003 -0700, Jim Harris wrote:
>I put up the same antenna about a month ago. The hardware on
mine was in
>fine shape......no problems at all. The balun is just as you
mentioned
>imho. The radials in my estimation are too small and the balun
is to keep
>RF from coming back down the coax shield. Looks to me like the
coax for
>the balun was of okay quality.
>
>The big problem I had was that the band width on 20 & 12 meters
is skewed
>towards towards the lower part of the band and there are no
adjustment
>procedures. Have to use a tuner on the upper part of the band.
Looks
>like just shorten the studs on the ends of the coils to raise
the center
>of the bandwidth. Not a clue anywhere as to how much to shorten
>them. Know where I can get a mfj-259 cheap. Hi!
>
>It does play a bit better than a carolina windom I've had up a
>while....and, seem liek it does DX much better.
>
>Jim
>
>
>
>Dinsterdog@aol.com wrote:
>
>>I recently put up a Cushcraft MA5V vertical for HF satellite
work. The
>>antenna is working ok- but since I can not find a human to
speak to at
>>Cushcraft, or anyone there to return emails, I have a question
about the
>>antenna design that maybe someone here can answer. If you look
at a
>>photo of the antenna, you'll notice a very large coaxial balun
at the
>>bottom of the antenna PVC support. The PVC isolates the
antenna which
>>sits about about 4 feet above the balun feedpoint, and the
balun is at
>>the bottom of the PVC support- - The balun form is about 2 3/8
inches in
>>diameter, 10 1/2 inches long, and it takes about 30 feet of
RG59 coax
>>twisted around the form to create the balun.......what's with
this
>>monster balun?? What is it doing??
>>I've never seen anything like it before- MY guess is that it is
overkill
>>to keep RF off the feed line- ??? Any thoughts on this?
>>BTW, the QC at Cushcraft is awful...I had to redrill, rebuild,
and modify
>>a lot of missing and/or misized parts- Blah! And the enclosed
RG59 to
>>form the balun is rat shack junk- But the antenna is working
>>FB! Seriously, it's working well above expectations-
>>73 Paul N0AH
>>_______________________________________________
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>>
>
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