> Absolutely stay away from the lesser-rated Millen connectors in any HV
application. The first-generation Alpha amplifiers used
> these connectors between the P.S. compartment and the R.F. deck. Even with
new connectors and 4 KV applied, all bets are off. I
> recall trying to localize a HV glitch problem in one of these amps and after
unsuccessfully trying everything else, I decided to
> bring-up the amp at low voltage (2.6 KV) with the top cover off and
subsequently noted a blue corona around the connector. I
> ditched the Millen connector in favor of a glazed-porcelain feedthrough and
have never experienced a single problem since. Later
> Alpha amplifiers simply passed the silicone HV wire through a chassis hole and
rubber grommet. This solved the flashover problem,
> but made servicing difficult. It's a shame that these connectors were
manufactured by Millen: Every other item in their extensive
> product line was designed and produced to perfection.
I have been down that road also, Paul! I solved the problem years ago when I
started mounting the
socket to the chassis a bit differently. I drill a hole in the chassis slightly
smaller than the width of the
socket. I then fashion a rectangle of 1/4" plexiglass slightly larger than the
dimensions of the socket. A
hole is then drilled in the center of the plexiglass slightly larger than the
shaft of the socket. Then
2- #6 holes are drilled through the plexiglass and chassis to match the mounting
holes on the socket.
This gives C. 1/4 inch separation between the socket and chassis. I have had
zero failures since I
changed the mounting scheme. Every failure previous to the change was right
where yours was;
where the shaft of the socket passes through the chassis. I would never dream of
pushing the
ratings above 6 kv. on the red or black units. The yellow units should never be
used > 1 kv,
IMO.
(((73)))
Phil, K5PC
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