>
>ok gang ,,
>
> Here is the story ,, at a recent hamfest I purchased a Hunter
2000 c
>* Bandit * . Aside from a shorted filament choke , open resistors , blown
>capacitors in the power suppy and visable burns on the plate of the tuning
>Cap
Burns on the Tune-C are often an indication of parasite oscillation.
>,
>it was in Good shape <sic> . I have just about finished repairing it and want
>to fire it up ,
Literally?
>thus my question . Finding the right filter capacitors was
>difficult , the originals are 140 MF at 475v ( 6 total ). I was only able to
locate this type
>ofcap at 450v and replaced them with these. The total voltage of these
>capacitors is now about the same as the plate voltage 2700v. I know from an
engineering
>view this is terrible ,, but ,, will it work ?
probably. However, if standby V exceeds 2700, there could be a big
surprise. . Is it a FWB or a FW V-doubler?
>Is there anything else I
>should
>be checking before bringing it up ? something I might have overlooked ?
I would put at least one 10 ohm, 10w glass-coated ww resistor in series
with the pos. HV lead to the PS in order to limit the peak fault current
in the event of a "glitch". I would also put a pair of 3A diodes across
each meter movement. Remember that newer radios cause older amps. to hot
switch, and that hot switching makes current transients which are an open
invitation to parasitic visitation. . High speed switching costs about
$60 for parts. // After the fils are lit I would measure the fil volts
at the sockets. . Today I got an e-mail informing me about a 3-500Z
commercial amp. that measures 6.5v on the filaments. Wowie, Bat Man!.
- good luck, Mike
Rich. Measures. Web site: www.vcnet.com/measures
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