I received so many considerate posts concerning the removal and
cleaning of TH6DXX traps that I decided to let the group know how the
first trap disassembly progressed. If you are not interested in this
process, stop reading now--I go to the bathroom once a month, and the
rest of this post is written in that vein.
Here is how I removed that first trap. This is an amalgamation of
almost every post sent to me.
I had already removed the first trap from the driven element and had
taken off the plastic end caps that slide over the cover tube. I
removed the setscrew that fixes the trap cover tube to the driven
element (this screw happens to be on the boom end of the trap). I
then SLIGHTLY pried the setscrew depression on the cover away from
the center tube, just enough to prevent rubbing when I would tap out
the center tube.
I then sprayed WD-40 (sorry about that Pat, but I had WD-40 and the
Liquid Wrench Store was 20 miles away) on the inside of the trap from
both ends, to let whatever was going to slide do so.
I clamped the trap and cover in a vise, sideways, using wood shims
(about 1/2"-thick junk pieces) on either side to protect the cover. I
clamped it only tight enough that it did not move when I subsequently
tapped.
I then tapped GENTLY on the end of the inner tube, the piece that
attaches to the rest of the element, using another piece of wood to
protect the end at which I tapped. I pushed the tube out by tapping
from the end with the setscrew depression toward the opposite end,
because the setscrew depression would have kept the plastic insert
from coming out of the cover tube.
What came out the other end of the cover was the inner tube, the
plastic inserts on that end, and the coil, still screwed tight to
the inner tube. That's what the trap is, a coil screwed to the inner
tube. The outer cover forms part of the capacitor. The two plastic
inserts jam against the coil. The plastic insert at the end where I
tapped stayed in place.
Thus far, the only piece that should be replaced is one end cap. It
is cracking a disintegrating, probably from sun and weather.
My big disappointment is that, despite what I could see through the
weep holes, this trap looks clean. There were a few pieces of
grass in it (I will have to get a lawnmower that does not throw grass
straight up 60 feet with enough force to jam it into the weep
holes), but nothing that looks like a problem.
Well, I am going to put the end caps back on and temporarily assemble
the pieces so I do not lose track of what I am doing, and then I will
remove the next trap. When I am finished, I will follow up on Zig's
recommendation and see if Hy-gain can replace whatever parts look bad
(like that end cap).
I again thank everyone who responded. I felt far more confident about
picking up that hammer after reading all the suggestions.
73,
Jan Ditzian
KX2A
kx2a@arrl.net
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