Rich wrote, in part:
>.Not only that, Lane, a Delrin core will assuredly melt and bubble at the
>kw level, as the ARRL Lab discovered with two MFJ "3kW" tuners
Yes, tuned up one evening to get a match on 160 using my 87A,
I heard an odd sound from the MFJ 3kW tuner, then a bit of smoke.
Shut down, took the case off, and several turns at the back
end of the coil had melted down into the Delrin!
Replaced the inductor with the newer MFJ air-core part, and sold
the box. Now using a Palstar AT4K. This unit comes with a built-in
blower to keep the inductor cool, should you ever feel the need
to run a bit more power, hi. Have never used it. Also has added
capacitors which can be switched in as needed from time to time
on 80 and 160, neat box, uses high cost/quality parts, so
is not cheap! Photo of the AT4K is at:
http://www.palstarinc.com/at4k.htm
a close up photo of the rear of the inductor area is at:
http://www.palstarinc.com/products.htm
Note, I have no connection to Palstar, just a
happy customer!
73, Jim, KH7M
On the Garden Island of Kauai
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