I just wanted to pass along my recent experience with a brand new XM240.
This antenna was a replacement for a 402CD that was destroyed in some strong
winds a couple years ago. Before I purchased the antenna I read a few
reviews and found one in particular interesting. I think it was a guy from
England who commented that his antenna worked fine for a couple years then
went south and developed high SWR. After much work he figured out the
connections within the loading coils were shot and corroded. I didn't think
anymore about those reviews until the day I started to put this antenna
together.
Cushcraft did a fine job making sure all the needed parts were in the 2
boxes. Near the end of construction I examined the 4 loading coil
assemblies. One of them had it's heat shrink layer, about a square inch,
completely carved out by a sharp knife to expose the self-tapping screw that
is used to connect the solid copper coil wire to the aluminum tubing. No
attempt was made to repair the hole that was left. Bad news CC !!! I
thought to myself it's ok...I can fix this with some rtv and a length of
heat shrink tubing. Luckily I had a 3' stick of some 1-1/2" tubing. Before
I made the repairs I thought I would check all the coils for good electrical
connections. Guess what? Out of the 4 coils one of them did not make a
connection across the coil to the tubing. I took an X-Acto knife and cut
away a portion of shrink wrap around the screws to take a look. I was
shocked to see that no attempt was made to remove the thick Red insulation
over the solid copper magnet wire. The self tapping screw did not cut
through the insulation on the one bad coil. I went ahead and removed the
insulation and reset the 2 screws and confirmed a good connection.
Then, I said I better check the others even though they were making contact
at the moment. It turns out none of the copper wires for all of the coils
had the insulation removed. By unscrewing the self tapping screws and
looking at the wire I could see that the contact area between the wire and
the screw was really really pathetic to say the least. The contact area was
miniscule. I removed the insulation for every connection and reset the
screws. Once nice and tight I applied some rtv over the screw and
surrounding areas and slipped some 1-1/2" heat shrink over. An hour or so
later I was back in action. The antenna is installed, and knock on wood, it
seems to perform ok. Just wanted to warn any current user or perspective
buyer to take a real careful look at these connections. Shame on CC for
letting this slip by.
73
Gedas, W8BYA
online image gallery at http://gedas.cc
e-mail address at w8bya@w8bya.com
web page at http://www.w8bya.com
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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