[Amps] Plate Choke Issue

AJ iamfromcanadaalso at gmail.com
Wed Jan 3 10:28:54 EST 2018

Hi people.

I have some sort of issue I have not been able to figure out or do not
understand the issue. I checked the bypass values the relay the wires

Ok here's the skinny, multi-band amp. Works fine on 160,80,40.
It was fine on all bands at one time; do not know what happens on 15 or
10 at this time. Tune the amp for ~2200 on 20 meters all is fine; get up
to 2600 obviously into the load. And kerbang! ! ! Blows the ceramic and
high voltage arc to some part of the chassis and a corona burn off of
the wire. 

Get a new ceramic insulator ( .75 x 4") as large as there is room. 
Wind 25 awg wire and ~65 cs turns on it. Fasten the ends to machine 
cir-clips. Measure inductance in the amp mounted 31.8 uh. Looked for
any series, checked for heating with 2 amps of current etc. Checked the
relay for function.

Well it lasted about 3 months, kerbang ! ! wife was in the room when it
happen. muwahahaha actually it really was not funny, 3650 vdc at the
choke, ~1 inch to any part.

So I dropped the number of turns now 27 uh, well that lasted about a
week, not sure how many tx's; again on 20 meters.

This time I was able to measure where it blew apart, ~20 uh from end to
end. I slid the wire off the broken ceramic and slid it onto a new one
mounted it in the amp to measure. I am referring to RFC-1

pic is here http://oi67.tinypic.com/2lwmb5u.jpg

What am I missing?


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