900 volts on pair of 6146, 6146A, 6146B is exceeding max ratings for the
tube. Not only is there overdissipation risk but also arc over. The
socket for the rectifier tube will also be close to breaking down. Mine
was definitely arced there, and I eventually solid-stated the HV
entirely. eliminating those tube sockets from the failure chain. This
did provide nearly 800 volts before key down. It dropped with carrier.
I don't remember whether the 1625s liked it, as they were quite rosy. I
replaced them with 6CA7/EL34s with a screen regulator.
125 - 130 watts output was typical in mine. Its pushing the tubes a bit,
but that's a personal thing.
The two series electrolytics and their bleeder are weaknesses in the
DX100, esp. given the vintage. Recommended to replace them up front and
don't take the risk of leakage in one causing the other to be
overvoltaged. Check the mid point voltage to make sure that this doesn't
happen, esp since the bleeder is tapped there to provide screen voltage
I believe (memory doesn't always serve me).
73
John
K5PRO
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