The small Bertan modules in particular are extremely stable and well-behaved. You get exactly the voltage that you program, accurate to within about a tenth of a percent. No spikes, no drift, and no obnoxious AF whine like you get from the HP modules.
The smaller ones are good for 500 uA, and the larger modules are good for 2-5 mA depending on model. -- john, KE5FX > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]on > Behalf Of J. Forster > Sent: Sunday, January 17, 2010 8:00 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 4 KV Power Supply Recommendations > > > The small modules are nice, but many PMT supplies do not go to 5 mA. 5 mA > @ 4 KV is 20 Watts output, more at the input. That's a lot for a PMT > supply. > > Also, remember that some supplies designed for gas lasers have a HV "kick" > at startup that may go to 20-30 KV. > > -John > > ============== > > > > > >> Since it appears to be making some progress, I'd be tempted to just > >> continue. The pump rate of an ion pump varies with the current, so it > >> seems you are pumping, just somewhat more slowly than w/ the external > >> supply, as long as you are not overloading the internal supply. > >> > >> If you don't have a lab supply, get an old transformer from some vaccum > >> tube gear and use the HV secondary to drive a Cockroft-Walton > multiplier > >> to get to what you want. Pretty trivial to build these days. Put the > >> primary on a Variac to adjust the voltage. > >> > >> BTW, a commercial supply at that voltage and current is going to cost > >> several hundred dollars. > > > > The nicer Glassman rack-mounted supplies are spendy, but smaller HV > > modules > > for PMT and laser work are common and inexpensive. Go to eBay > and search > > for "<manufacturer> supply", where common manufacturers include Emco, > > Bertan, Spellman, Fluke, and Glassman. E.g. item 220539685243 . These > > smaller modules tend to sell for well under $100, and are handy to have > > around. > > > > -- john, KE5FX > > > > _______________________________________________ > time-nuts mailing list -- time-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
