Thanks to all- found the issue(s). 1.) The cap bank, if not breaking
down from carbon tracing at normal operating voltage, was probably close to
doing so. 2.) The tranformer is shot- it reads 80k ohm from either primary
to any of 4 secondary taps, and hipots infinite leakage after a few 100
volts (no movement at all on the HV meter needle at any voltage level...)
2nd HV transformer I've lost (1st was in an SB220 I "over-contested" without
extra air) but never saw one that would "idle" without a load of any sort
like this. I compared it to an unused Dahl hypersil I have here w/ the same
secondary rating- it had 7-10 micoramps of leakage at 7kv (wasn't game to
push it higher). Going to replace the works obviously.
Appreciate all the advice.
73 Dave N3DB
----- Original Message -----
From: "Bill Fuqua" <wlfuqu00@uky.edu>
To: "Steve" <g8gsq72@gmail.com>; <amps@contesting.com>
Sent: Wednesday, July 13, 2011 10:28 AM
Subject: Re: [Amps] GS35b FWB issue
> My first novice transmitter developed a novel problem.
> When it warmed up the 5U4 would arc over. Turned out that
> a number of turns in the primary were shorting out causing
> a sudden jump in the secondary voltage thus the arcing and
> fuse blowing. Never ever seen this again.
> 73
> Bill wa4lav
>
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