RE HY-Gain TH3 Traps.

Going back some weeks I  mentioned here that I was rebuilding a TH3Jnr.
Beam.

I was having no luck in getting the replacement plastic end seals for the
traps
From either HY-Gain/MFJ/W&S. and tried for some weeks.
As mine had all split and were letting water in

As the weather was getting to a point that maybe I could not carry out the
repair until
maybe the turn of the year.
I enquired on the group if maybe a good grade shrink sleeve ( glue type
interior  )
would do the job.
There were thoughts from guys but no one seemed to have tried using it in
practice.
Now I know DON'T USE IT FOR THIS PURPOSE.

I got the beam rebuilt and I must admit the shrink sleeving done a great
job.
It looked the part was nice and firm and mechanically stable more ober I
felt
it would be more weather proof than the originals, I was well pleased.
But on getting the beam back up .

20 metres side checked out with my analyser at 13.850 for best SWR
15 metres at  20.500
10 metres at 27.600.

My first thought was that the scaffolding up near the beam was effecting
it..
Or I had mixed up the traps.!!!!!!!!!!

I decided to leave well alone until the scaffolding was removed.
When it was it did not alter the above resonant points much.

So I decided to get info on the TRAP Winding turns in case I had mixed them
up.
Asking on most of the forums about windings got no replies.
At this time I did get a reply from HY-Gain and ordered the Trap seals.
As I have another TH3 to refurbish for a friend.

I got the trap info eventually from HY-Gain.
I took the traps off the driven element, cut off the shrink sleeving.
And the traps were the correct windings. I refitted the driven element using
the new PROPER coil seals.

When checked again it was correct in each band.!!!!!!!!!!!!!!!!!!!!!!!
So the Reflector and Driven element were re-done with the seals from
Hy-gain.
All I can think is the Shrink Sleeve was adding some C to the ungrounded end
of
the covering alloy tube over the trap coil.

The end seals are  US$1.59 and it needs 24.
Post costs were US$15.00
P/O charged £8.00 to get it from customs and £3.56 VAT on the lot.

So quite an expense to do the refurbishment..
But you now know someone that does know the Coil Turns at least.

I good result at the end , but at the time one I could have done without.

de Johnny G3LIV
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