I received a good memory tweak from AF2C about Amperex tubes in Drake
amps. Went down into the dundgeon and read the L-7 manual...the L-4 is
similar.
In the Maintenence section it lists expected idling currents for the
following:
TUBE CW SSB
Amperex 3-500Z 100ma 160ma
Amperex 3-400Z 100ma 160ma
Eimac 3-400Z 110ma 170ma
Eimac 3-500Z 170ma 220ma
>From the above it would appear that the Amperex tubes are operating
deeper into the Class B region with the operating bias and HV remaining
constants. A bit more tendency toward instability wouldnt you think?
Also a bit harder to drive to say 1000W but also capable of a bit more
output when pushed. I'm pushing the memory here but I believe that the
Amperex tubes peaked at about 275-300 ma grid current and the Eimacs at
250-275ma in a PT-2500A I used to own.
73....Carl KM1H
Comments?
73...Carl KM1H
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