On 2 Feb 98, Pat Barthelow <aa6eg@cv.tmx.com> wrote:
>
>
>
> Hi Folks,
>
> We at N6IJ, have suffered a failure of our Hy-Gain LP 1017 Log periodic
> antenna. :*( It has gone high SWR intermittently for several months.
> Careful
> troubleshooting has eliminated as possible sources, all transmission line
> fitting problems betweeen the shack and the final pigtail lead located at
> the kingpost/Rotor. Sweeping the coax pigtail shows infinite (nearly) SWR
> through the entire range (6.2
> to 30 MHZ.) The antenna uses the Hygain BN-86 ferrite balun. The
> antenna is mounted on a standard ARMY MARS platform, trianglar, 18 ft
> corner to corner. The Balun, at the tip of the boom is 25 feet out from
> the edge of the platform, so is difficult to access. I need to locate a
> cherry picker, or crane with Man-Bucket to look closely at the feedpoint.
>
> Question: Can I/Should I replace the ferrite balun with a coil
> balun, made of coax? Or should I replace the BN 86 with a more rugged
> Hygain ferrite Balun? (I'm assuming the balun has failed internally, as I
> have
> been told that this particular model was subject to unreliablity when used
> at high power levels. We use up to 1200 watts out, but who knows what the
> ARMY MARS OPS used when the ex MARS station at Ft. Ord was active.) If I
> fabricate a coil balun, for 40 thru 10 meters, how many turns and
> what diameter should I use for the RG-213 Coil?
>
> Tnx, de Pat, AA6EG/N6IJ; aa6eg@tmx.com
> The Contest Station from the Government
>
> Marina Amateur Radio Contest Station
> 599 DX Drive
> Marina CA 93933
>
I have used Hygain's BN-4000 on my TH7s for several years at full power
RTTY with no problems. It fits right in the same spot as the 86 for a
neat appearance.
If you want to buy another BN86, I have an unused one, that came with
my TH7...
73 Barry
--
Barry Kutner, W2UP Internet: w2up@itw.com
Newtown, PA Frankford Radio Club
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