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.
At what frequency? 450mA at 1500V is only 700W input so 500W output is
rather good. I assume from the grid current, you have it loaded wrongly,
but that might be right for the 811A. You should have much more plate
current.
1. Are the tuning and loading capas still within range.
2. Is your power meter OK - seems rather generous.
3. Do you have enough drive and is it getting to the bases.
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