The best advice. Its making progress. Give it 2 weeks of steady on time and watch the voltage as you are doing. I just tried to recover HP 5061A form the US Naval Observatory and though the tube pumped down fine, unfortunately for me after tons of checking the tube is bad. Very very low CS emissions.
On Sun, Jan 17, 2010 at 11:00 AM, J. Forster <j...@quik.com> wrote: > 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.