Hello to the group. I have to agree with Joe on the addiction. I was the one asking strange questions about 8 months ago as I glued together the Frankenstein of 5061s. It used a tube that was given to me by a fellow time-nut that was bad that however actually had a few more fumes of CS then my 004 tube. I home brewed a new oven controller to allow me to bake the remaining Cs off. The crazy thing actually worked kind of barely. But a great lesson in the actual physics and other wonders. So it still works but I have to say I now understand why they left them on all of the time. Maybe a real tube with 15-20 ua would be a far different story. I suspect so. But what are you going to do for a hobby. Let me know if I can help. Regards Paul WB8TSL
On Thu, Feb 23, 2012 at 8:30 AM, J. L. Trantham <jlt...@att.net> wrote: > The Ion Pump I is measured as a voltage across a resistor in the +3500 VDC > supply in the return path from ground. This supply is capable of providing > only a small amount of current and will collapse to zero volts if > overloaded. Likewise, it can fail for a number of reasons, due primarily > to > it's age. It can be repaired by opening it using a 'torch' to melt the > solder seal at the bottom. Keep the heat low, along the bottom. The 'lip' > is only about 1/8th of an inch or so. > > I have had issues as you are referring to for a number of reasons: > > 1. A CS tube with a short from the +3500 to ground. Fixed by using the > +3500 VDC supply to charge a 4 uF 4 KV capacitor then 'discharging' the > capacitor through the CS tube's +3500 connection to ground (be careful if > you wind up trying this). > 2. Failed +3500 VDC supplies for a number of reasons including an internal > 'shunt' (not quite a 'short' but becomes as much at high voltage) of the HV > lead to ground, shorted internal electrolytic on the +18 VDC supply > Line, and open HV diodes. > > The unit I recently purchased has an FTS tube, known to, typically, have a > very good 'vacuum' and low Ion Pump I. It is functioning because, when the > CS Oven turns on, the Beam I goes up, slowly, as it should. In addition, > at > initial turn on, the Ion Pump I went off scale, as it typically does when > first turned on after a long period of inactivity, then fairly promptly (30 > to 60 minutes) 'pumped down'. > > These units are fun to play with but are terribly addicting. Be careful. > You might wind up with several. > > Joe > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of Azelio Boriani > Sent: Thursday, February 23, 2012 4:57 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] 5061's on ebay > > > The ion pump current at 0 is not good. At work they bought an FTS4065B > without telling me before: instead of a very old FTS4065, there is an > already working PRS50. Anyway if the ion currect is 0 check the HV > generator > first. Check this http://www.ke5fx.com/cs.htm on how to try to reactivate > the ion pump using an external HV power supply. > > On Thu, Feb 23, 2012 at 5:28 AM, J. L. Trantham <jlt...@att.net> wrote: > > > I think so. But time will tell. > > > > I also have some units with bad tubes and this looks promising. > > > > Joe > > > > -----Original Message----- > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] > > On Behalf Of Tom Knox > > Sent: Wednesday, February 22, 2012 10:20 PM > > To: time-nuts@febo.com > > Subject: Re: [time-nuts] 5061's on ebay > > > > > > It sounds like you hit a home run Joe. If the tube is good the rest > > should be easy. There are quite a few clean clocks with only a bad > > tube. > > > > Thomas Knox > > > > > > > > > From: jlt...@att.net > > > To: time-nuts@febo.com > > > Date: Wed, 22 Feb 2012 21:15:59 -0600 > > > Subject: Re: [time-nuts] 5061's on ebay > > > > > > I purchased a 5061A with all parts installed and with the FTS tube. > > > The 5061B with the FTS tube was listed later and sold. > > > > > > The unit seems to operate with good Beam I, good 2nd Harmonic, and > > > almost zero Ion Pump I but it will not 'lock'. I have not had a > > > chance to look into it yet but I suspect an issue with the A7 or the > > > A8 assemblies. > > > > > > If anyone is interested, I'll keep you informed. > > > > > > Joe > > > > > > -----Original Message----- > > > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] > > > On Behalf Of Dave Welch > > > Sent: Wednesday, February 22, 2012 9:09 PM > > > To: Discussion of precise time and frequency measurement > > > Subject: Re: [time-nuts] 5061's on ebay > > > > > > Hi all. > > > I PURCHASED THE FTS UNITS AND ONE OF THE HP5061a. Havent had time to > > > look at them but one of the fts powers up but i dont have any docs > > > to figure > > out > > > what os wrong..it says ion current is 0. > > > Should this be that low?? > > > On Feb 22, 2012 3:21 PM, "Tom Knox" <act...@hotmail.com> wrote: > > > > > > > > > > > The same seller also had some 5061B's and FTS 4065A's as well, all > > > > were untested or in various states of disrepair. I was tempted on > > > > a few the > > had > > > > missing parts not related to the Tube. Did anyone purchase any of > > these? > > > > > > > > > > > > Thomas Knox > > > > > > > > > > > > > > > > > Date: Wed, 22 Feb 2012 15:17:42 -0500 > > > > > From: bow...@gmail.com > > > > > To: time-nuts@febo.com > > > > > Subject: [time-nuts] 5061's on ebay > > > > > > > > > > There are 3 5061's listed on ebay at the moment. Anyone know > > > > > anything > > > > about > > > > > them? > > > > > _______________________________________________ > > > > > 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. > > > _______________________________________________ > 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.