I generally use an external HV PS and bring the unit up slowly, roughly 50 VDC per step and let it sit for several hours at each step. Reforming caps is a chemical process, and does not happen in microseconds.
-John ============= > J. Forster wrote: >> With tube gear, one fairly good way to reform the caps is either pull >> the >> tubes (label where they came from) or disconnect the filament supply, >> and >> then apply B+. You do need to check the schematic to make sure you don't >> overvoltage caps that would see an increased voltage w/o plate current. >> Also, cathode bypass caps may never see the reforming voltage. >> > Good advice, but leave the rectifiers (80, 5Y3, 5U4 etc.) in their > sockets :-) > > Bill K7NOM > >> For solid state equipment, the light bulb thing will limit collateral >> damage on simple rectifier-filter analog supplies. Switchers are more >> problematic. >> >> -John >> >> ============= >> >> >> >> >> >> >>> And vacuum tube equipment using indirectly-heated cathodes: >>> http://www.cpii.com/docs/related/23/Basic%20Tube%20Design.pdf >>> >>> "Operating techniques that are proper for filamentary tubes are not >>> necessarily >>> correct for tubes with indirectly heated cathode emitters. In >>> particular, the opera- >>> tion of cathode types at reduced heater voltage can be destructive to >>> the tube." >>> >>> Leigh. >>> >>> Mark Sims wrote: >>> >>>> Be very careful powering up modern equipment on variacs and with light >>>> bulbs in series, etc. You go through areas where the bias voltages, >>>> etc >>>> are in the right place to cause serious damage. Switching supplies >>>> can >>>> be particularly entertaining... >>>> >>>> ---------------------------------------- >>>> >>>> >>>> >>>> >>> _______________________________________________ >>> time-nuts mailing list -- [email protected] >>> To unsubscribe, go to >>> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >>> and follow the instructions there. >>> >>> >>> >> >> >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to >> https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. >> >> > > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
