RB wrote:
Charley, It sounds to me likely to be a plate to grid short in one of
the 3-500Z tubes rears it ugliness only intermittently, sitting idle.
This is a common mode of failure with old 3-500Z tubes.
I believe he said it was a NEW amplifier...although even "new" tubes can
develop a short.
It could be accelerated by higher than 5.0 filament voltage
This could be a possibility. I am the second owner of a ca. 1994
Centurion and my filament voltage was above 5.0 volts with "normal" line
voltage. My best guess was the filament windings should have had a turn
or two removed. As I was the second owner and did not want to invest in
a new transformer (with no assurances that the new one would be any
better), I modified the rig by putting a resistor in series. This was
done 8 or 9 years ago and I still have my notes (but not right in front
of me) and it has been working well for all those years.
I suggest that you obtain and install a new pair of Premium Grade
matched Taylor Brand 3-500ZG-RFP tubes from RF Parts
again, a new amp. Hopefully his warranty is still in effect!
I also might suggest that with an amplifier using 3-500Z type
"Instant On" tubes, you will increase longevity of the tubes, as well
as save on your electric bill by turning the amplifier off whenever
you do not anticipate it use during the upcoming 10-15 minutes. Since
the tubes require virtually no warm up time, turning them off when
not in use is a preferred mode of operation.
In theory, this seems like a good idea. However, I thought I read that
the most "wear" on an incandescent filament (tube or lamp), occurs from
the surge when first turned on and can significantly -shorten- the life
of the filament. Comments?.
-----Original Message----- From: tentec-bounces@contesting.com
[mailto:tentec-bounces@contesting.com] On Behalf Of Charles Delaune
Sent: Sunday, October 08, 2006 11:42 AM To: TenTec@contesting.com
Subject: [TenTec] Centurion Amp Woes
I'm having an on going problem with my NEW Centurion.
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