I think you have an intermittently shorted tube. This is why your old
filament transformer smoked. There is a reason for re-wiring the antenna
relay to keep from burning up the filament transformer. Details are on Rich
Measures site. (I know I know....)
If a tube shorts, it also shorts out the filament transformer. I don't
remember the exact current flow but Rich explains it.
73
Jim W7RY
----- Original Message -----
From: "Jeff Carter" <amps@hidden-valley.com>
To: <amps@contesting.com>
Sent: Wednesday, February 04, 2009 8:51 PM
Subject: [Amps] SB-220 and Xfrmr Smoke...Part 4
> Okay, the replacement transformer is installed, and life is
> good...except I'm beginning to think this amp is haunted.
>
> All voltages were checked and are present. Never again when working
> on an amp will I assume that just because somebody sold me something
> that it's good. I should have known better.
>
> The haunted part: At odd intervals, the meter needles will *twitch*.
> The plate current, which is sitting on zero, twitches up to maybe 50
> milliamps, the HV needles twitches down a few volts, and then, as
> quickly as it started, everything goes back to normal.
>
> What's going on with this? Do I have another problem to find?
> Nothing's hot, nothing's smoking like before, this just seems odd
> behavior to me with no drive or anything.
>
> Has anybody seen this problem? Or is it just a normal thing when
> everything is new like this, with things settling in?
>
> Thanks again,
> Jeff/KD4RBG
> _______________________________________________
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> Amps@contesting.com
> http://lists.contesting.com/mailman/listinfo/amps
>
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