Time to draw on the collective wisdom of the amplifier gods again....
I got the new Svetlana 811a tubes from RES in today and dropped them in tonite,
but still can't get full power out of the amplifier. I can load the amp up with
up to 200ma grid current, 450 ma plate current and 1500v high voltage, but the
most I can get out of it is 500 watts cw.
I originally thought that maybe because of the plate to grid short in the
original tube that maybe there was something wrong still in the driving section
on the tubes, ie a bad cap or something, so I pulled out 2 tubes and could
still get the same amount of power out of the amp, so then I pulled 2 diagonal
tubes out and did the same test and got the same results.
So this rules out that there is still a problem with grid resistors/series
blocking caps etc. Going from 2 to 4 tubes only changes the output by 5-10
watts, and doesn't change the plate/load tuning much at all either.
Help! Anyone got any ideas besides send it back to Ameritron? This is a last
resort option, as I really don't want to ship this.
Thanks in advance,
Scott
KA1CLX
<bold><bigger>
Advantage Communications
</bigger></bold>Professional Wireless Communications
www.radiosonline.com
800-851-RADIO
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