Traps for Hygain TH5/TH6
TSkelton at engineer.clemsonsc.NCR.COM
Wed Apr 7 16:45:00 EDT 1993
This is not directly related to contesting, but since we are
always working on, talking about, praying for, cussing, and
building antennas, I didn't think you guys and gals wouldn't
mind if I posted this.
I promise not to discuss any aspect of 24 hour contesting in
this post, so read on.
A couple of years ago, during a heavy rain and while trying to
work Romeo from XY0RR on 15 meters I had a huge spark in
my venerable SB220. I stopped transmitting, and retuned. It
seemed to go away, but the band was acting like it had been for
some time: dead. Everyone else seemed to be hearing Romeo
4 or 5 S units better than I was. Also, the SWR while it was
raining (a heavy downpour) went from almost flat to 4:1. I
had noticed this before, but not as badly...it would go up to
2.5:1 or so and then when dry weather came it would go back
down. (The station I was comparing Romeo's signal strength
to was using a TH7 at 100 feet; I had the TH5 at 80 feet and
Burma/Southeast Asia is my best direction.)
Remembering back to the days when I blew the trap on a TH3jr
while running 500 watts on 15 meters (Hy Gain told me I could do
it!!! The devil made me do it!!!), I assumed I have now blown the
15 meter trap on the TH5. I almost had a heart attack when
Hygain told me how much a replacement pair of traps would cost
for the TH5: $75 per pair!!!! They also said if my trap "blew" it
was not repairable. (NO, I was NOT running an Alpha 77SX ....
just my standard SB220.)
As best as I remember, the 10 meter band seemed OK but I can't
remember being able to hear on 20 very well. So as not to miss
XY0RR I took down the TH5 and put up my back up antenna --
a Hygain 3 element 20 meter monobander.
Anyhow, could some of you ladies and gentlemen give me some
advice? Do you know of any place to get replacement traps for
Hygain antennas besides directly from Hygain? Is it possible
that the traps had gotten "critters" in them and, combined with
the moisture, caused a temporary short and the resulting high
SWR and the also resulting spark in the SB220??????
Is it possible the traps are OK, and I just corrosion in some of
the element joints? Have any of you experienced a similar situation?
I want to get the antenna back up, and am in the process of
disassembling each element, cleaning the joints, and replacing
Thanks in advance for your advice and suggestions. I wish I
had more data to share with you, but I do have one more point:
I thought maybe the coax had gotten water-logged and that
was causing the problem. Nope....I put fresh RG8 on it and
the SWR was still high and the bands still sounded "dead"
compared to other stations.
73, Tom WB4IUX
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