[Hallicrafters] Antenna info ?

Wed Feb 27 09:08:54 EST 2002

Phil, 	

As you know, I run a Hustler 6BTV and have for almost four years. I doubt this
is weather related, as overall, conditions in Michigan are more adverse than in
California. We get some pretty good winds here also.	

First, the obvious. What else around the antenna has changed that contains
metal? As I recall, you put up a large loop antenna for beacons? You may have
detune the Hustler if the proximity is close. Because you are on a small trailer
park lot, this may be a factor. I recall you did not have this problem before
the addition of the antenna for the beacons. 	

Next, i strongly suspect that the Hustler is somehow using part of your other
antenna systems, or station ground system, and altering its point of resonance.	

I think you need to look at the coax, all PL-259 and SO-239 connectors, all
solder points on the connectors, shorted coax, water in the coax, antenna switch
box and so forth. 	

Unless something changed radically, and it should be obvious visibly, the
problem is not apt to be the Hustler 6BTV proper. Get Don to come over with an
antenna analyzer and check the antenna. If he does not have one, he probably
knows somebody in the area that does. 	

This problem also started when you started using the antenna to transmit. You
mostly used it for receive, as I recall. But what you ran for a TX, a Kenwood?,
did not have enough power to do any harm to the antenna.		

Here is one thing I have seen happen. If water got into the coax, or into a
double female connector joining the feedline from the Hustler to the feedline
into the QTH, when you applied RF it would short and burn the coax near the
fitting. I had this happen here with a GAP Titan. The point of connection was
covered with sealant tape, supposedly waterproof. But it obviously was not. A
little water wa sufficient to cause the short. Just 100 watts actually blackened
the coax. The SWR went up as a result. Yours may not be as severe as mine was,
but it is worth considering.	

Duane W8DBF 

----------
From: Phil Atchley <ko6bb at elite.net>
To: hallicrafters at mailman.qth.net
Subject: [Hallicrafters] Antenna info ?
Date: Tuesday, February 26, 2002 5:51 PM

Hello
This is indirectly related to Hallicrafters as this antenna IS used for
receiving on the 5R10A and (future) SX-71.  I don't belong to the antenna
reflector and I figure there are some good gurus on this list.

I have a Hustler 6BTV vertical that was put up a little over 2 years ago and
performed flawlessly for a couple years.  (it is over  > 1000 Sq/ft of
sheetmetal roof/awning.)  The unit was guyed (per Hustlers instructions) at
the 20M trap, especially as we get some good winds here.  I used some Nylon
Twine as the guys, it is still holding well so it didn't "sun rot".

It has since developed problems, high SWR's Especially on bands below 20M
and I suspect that the outer sleeve on the 20M trap 'may' have slipped down
some from the constant downward  pressure of the guys, detuning the trap.
(the various tubing sections were all secured against slipping by setscrews
after it was tuned).  Does this sound feasable?  While up there I intend to
replace all the coax from antenna to the antenna switch in the shack as
insurance.  (I use RG8X as I don't run any 'power' over about 100W maximum).
I want to do EVERYTHING in one trip to the roof as I don't want to walk on
the mobile roof more than needed.  My wife says she can tell exactly where I
am by looking at the ceiling  sag 8^(

My present (best) SWR's are

29.7   2.0 (10M is about as it was, I didn't wish to cut tubing)
28.0   1.3
21.3   2.0 (never had a really good SWR but was much better)
14.35 1.8
14.1   1.4   (Was tuned to Phone band)
10.15 2.0   (Was 1.5 at 10.1MHz)
10.0   1.2
7.1     2.0   (was tuned to 7050)
6.97   1.3
3.67   2.4   (was 1.4 at 3.908 net freq)

If the trap is detuned, any hints on getting that sleeve in the right spot
again?  I don't have a grid dip meter.  Also, I never had to tune a trap
before, how critical are these Hustler traps.  Any ideas?

73 de Phil  KO6BB
Loving home provided for wayward Boatanchor Receivers
ko6bb at elite.net
Merced, Central California
37.18N 120.29W CM97sh

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