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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