[R-390] "Fake" 12AX7 tubes on e*pay

[Roy Morgan]

At 09:42 AM 2/17/2006, you wrote:
>I needed a couple of 7027's for a couple of old Globe Scout's I'm
>rebuilding- found some Chinese 6L6GC's cheap and will try them- have some
>SOvtek also so will do some comparison.


Sam,

If the plate voltage is high (550 or so) in the Scout, you can expect the 
Chinese tubes to self destruct.  Better get some advice from the guitar 
guys before you endanger your transmitter.  In many guitar amplifier repair 
shops there is a bucket for burned out transformers and chokes that died 
from the use of chinese 6L6's and other such tubes.  The Chinese 2A3's in 
audiophile amps that ran near max conditions for genuine UhMurrican tubes 
were particularly prone to failure.

I would trust the Sovtek's more. At least try them first, so that when you 
fry your power transformer with the Chinese ones you'll at least have had a 
chance to see how the Sovtek's worked.

Your best bet is to use Tessla E34L's (and rewwire the socket if needed) if 
you think the filament supply is up to the increased current draw.

Sorry to be pessimistic.

Roy


- Roy Morgan, K1LKY since 1959 - Keep 'em Glowing!
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