Ill check that out as well. I just replaced the full bias board with a spare I
had and is working now. So its off to find the bad part.
Thanks..
-----Original Message-----
From: Amps [mailto:amps-bounces@contesting.com] On Behalf Of Joe Giacobello
Sent: Saturday, October 27, 2012 11:50 AM
To: Dave Hachadorian
Cc: amps@contesting.com
Subject: Re: [Amps] High grid current Titan 425
I am not at home right now, but if my memory serves, R117 on the bias board is
a potential source of your problem. I believe it's a 4.1 ohm or so precision
resistor. I've had it open up on a couple of occasions when someone gave me a
bad set of 3CX800s and when I've accidentally overdriven the final. The usual
symptom is high grid current.
73, Joe
K2XX
On 10/27/2012 2:41 PM, Dave Hachadorian wrote:
> I have a big hand-written note in my AL-1500 manual that says "If
> metering is screwed up after an amplifier 'event,' check the diode
> that goes between B-minus and ground."
>
>
> Dave Hachadorian, K6LL
> Yuma, Arizona
>
>
> ----------------------------------------------------------------------
> ----------
>
> I just had an arc happen on my Titan 425 this morning that blew the
> fuses in the PS. When I replaced them I had high voltage to the RF
> deck, but I'm seeing high grid current now with just 20 or so watts of
> drive. Output is very low.....less then 100 watts.
> Do I have an issue with the tubes? Thoughts?
>
> Thanks. Rich. N7TR
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> http://lists.contesting.com/mailman/listinfo/amps
>
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