>Have a new old SB-1000 with a 3-500Z. Turns on, lights up, HV ok, but
>tube arcs and fuses blow.
** How is it known that the tube arcs?
>-looks good, nothing looks or smells cooked
>-diodes test ok
>-lights up ok without tube
>-transformer windings ok tested at 1000V
>Before the tube arcs (I hear it)
** If the arc makes a loud bang it is not inside the tube, it is in the
>the tube glows at the base(10-30
>seconds til arc).
** What color is the glow?
>Have read about restoring tube by "running low anode voltages and
>positive bias on the grid". I guess I am asking how to do this?
** Check tube (filament not lit) with a high-potential tester: If the
anode/grid leakage is under 10uA, and the grid-filament withstanding
potential is >5000v, chances are good that the tube is too.
have phun, Tim
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