>
>> BTW, gud deal..only $102.00 matched) one of the tubes went into parasitic
>> oscillation and before I could kill the main power switch it finally
>> killed the circuit breakers. Now this one tube has a burn spot on both
>> sides of the anode and the tube glass adjacent to it is mirrored. Does
>> this necessarily mean the tube is weakened/not matched to the other
>> tube?? I don't have a hi-pot to test them.
>
>Well, it might be good....or it might not.
>
>I have another suggestion. When testing for oscillations, put a large
>value high wattage resistor in the filament return to the B minus.
>
>Normally I put a large high wattage lamp in series with the return,
>just be absolutely sure the insulation is good and the negative rail
>of the supply is clamped to the chassis through a big protection
>diode.
>
>Then you can let the tube oscillate while you run for the switch. A
>good idea is also to FUSE the HV supply for a reasonable current.
>Fuses, even by the dozen, are cheaper than tubes.
? Not high voltage fuses. Are you suggesting that 250v fuses are
suitable for fusing the anode supply?
Rich...
R. L. Measures, 805-386-3734, AG6K, www.vcnet.com/measures
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