Hi I agree that Switcher CAD is a great little SPICE program. Well worth every dime I've paid for it ..
The only issue I see with using it for this kind of thing is not knowing the details of the transformer. All kinds of fun things can happen if you accidentally resonate the secondary inductance. Of course you could indeed get a transformer and measure it ... Bob On Jan 17, 2010, at 10:31 PM, Didier Juges wrote: > Joe, > > Use Linear Technology's SwitcherCAD to simulate the operation of the > multiplier. It is a great tool, and it is free, and you will learn a valuable > skill. > > And it is a lot safer than breadboarding a 4kV supply. > > Didier KO4BB > > > ------------------------ Sent from my BlackBerry Wireless thingy while I do > other things... > > -----Original Message----- > From: "J. L. Trantham" <jlt...@worldnet.att.net> > Date: Sun, 17 Jan 2010 21:13:34 > To: 'Discussion of precise time and frequency measurement'<time-nuts@febo.com> > Subject: Re: [time-nuts] 4 KV Power Supply Recommendations > > The more I read about this, the more I think I will just let it 'pump'. > > This evening, the voltage on pin 4 is -1.039 VDC and the HV is up to 2151 > VDC. > > I was wondering how to limit the current capacity of an old HV transformer, > say 750 VAC, power supply and I suspect it is all in the size of the > capacitor. I will have to do some calculations about that. I was thinking > of using enough diode/capacitor units to multiply up to around 5 KV with a > variac to drive it and have taps from the diodes along the way for lower > voltages as well. If I can just find my old transformers. However, the way > work is now, I suspect the tube will be pumped down before I get around to > this. > > I'll keep my eyes open for HV power supplies on eBay as well. > > Thanks for all the info and I'll let you know what progress occurs. > > Joe > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Stanley Reynolds > Sent: Sunday, January 17, 2010 8:38 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 4 KV Power Supply Recommendations > > > Yes even with the mods odds are good the secondary is not well isolated from > the frame and even with the extra secondary windings the primary loading is > high per turn and load regulation is poor. Over all microwave transformers > are not very good, if you goggle them plenty of info and speculation about > them. If > you have a matched pair you can turn then into a center grounded > configuration. There are ways to limit current and voltage like the > incandescent bulbs in the primary, or the autotransformer already > mentioned, but mistakes could be costly. HV resistors or strings of > resistors could also be used in the secondary to limit current. > > / rambling on > Not sure working on very old cesium standards is very safe much less using > factory made PS at KVs to revive old tubes but some people jump out of > perfectly good air planes in the name of fun. HV power supplies are scary > and yes I have ended up on the other side of the room with a odd metallic > taste in my mouth, not sure why I lived so long ? $200 to ebay sounds better > than the cost to replace a time-nut, at least this one:-). If you do live to > see your homemade power supply working maybe your luck will hold with the > tube repair, did for me but I only got a few months of lock light and I'm > back to square one. / rambling off > > Stanley > > > > ----- Original Message ---- > From: Bob Camp <li...@cq.nu> > To: Discussion of precise time and frequency measurement > <time-nuts@febo.com> > Sent: Sun, January 17, 2010 7:33:16 PM > Subject: Re: [time-nuts] 4 KV Power Supply Recommendations > > Hi > > You also could leave the windings as is and feed the secondary voltage into > a voltage multiplier. Still not very safe to wire up. > > If you did wire it up, the available current would be pretty massive. I > certainly would not attach it to an ion pump I cared about. > > Bob > > > On Jan 17, 2010, at 6:53 PM, Stanley Reynolds wrote: > >> >> >> >> >> ----- Original Message ---- >> From: Chris Stake <st...@btinternet.com> >> To: Discussion of precise time and frequency measurement >> <time-nuts@febo.com> >> Sent: Sun, January 17, 2010 5:05:01 PM >> Subject: Re: [time-nuts] 4 KV Power Supply Recommendations >> >> What is the operating voltage of the magnetron in a domestic microwave >> oven? Although VERY HAZARDOUS, it might be possible to adapt the PSU >> from an old one? Chris Stake >> >> Yes, if you remove the transformer shunts and the filament windings >> and add more primary windings in the space you would get about 2700v >> with a full wave bridge. You also need to lift one side of the >> secondary that is grounded to the frame. Yes very dangerous and yes >> I'm luck to be able to tell. >> >> Stanley >> >> _______________________________________________ >> 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. > > > _______________________________________________ > 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. > _______________________________________________ > 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.
