>:The power transformer seems heavy enough to perhaps be used in a
>:voltage multiplier to incorporate some other more suitable type of
>:transmitting tube, say either a single 4CX400 or a 4CX800 maybe.
>
>Yes, it has been done. but the duty cycle must be low. ie ssb The
>transform runs very warm.
>
>:The tank components seem heavy enough to accommodate perhaps up to
>:800 watts or a bit more in a less than contest use amp...
>
>pretty much SSB operation only...
>
>:With the high cost of sweep tubes ($30 or more each) and the cost of
>:a single 4CX400 by Svetlana at $130 and the 4CX800 at $190 plus $22 for
>:the socket these look like a possible alternative. Am I on to something
>:here or have I missed a better mod/rebuild? Perhaps a pair of 4CX250B's
>:with the G3SEK tetrode board?
>
I think the tank circuit components in the amp (particularly the plate tuning
cap) would not survive operating with tubes at plate voltage higher than stock;
my GLA1000B, with healthy tubes running off a stiff, slightly high 220V source,
arcs occasionally even into a dummy load - the arcing is in the plate cap and is
usually a problem only when it's sat for a while and is dusty (a clean-out
with the air compressor completely fixes it, so I think it's just the matter
of at-limit components in that area).
Dave
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