Hi, About five years ago I purchased a rubidium standard on eBay. It was an Efratom.  Sadly although  The oscillator was working but it wouldn't lock.  I was comparing it to a HP Z38001A which I use as the frequency standard in my lab. I tried to fix it, but I couldn't find the correct schematic so I abandoned the project. I would like some advice on where I could get a working one and how much I should pay. -- Best Regards Rob Garnett Toongabbie Vctoria 0351 489484 0417 995 247

Hi Rb standards have a finite life. Just how long that is depends a lot on how good a job the heatsink on them did as well as the run time. They do die of fairly normal random stuff as well. Like just about everything designed in the last 30 years, schematics and field repair manuals simply don’t exist. What to do: Start looking for shorted caps. If voltages are ok then move on to things like the frequency of the local oscillator. You can get surplus Rb’s built into functioning devices. Typical price seems to be in the $500 and up range. The advantage is that at least it worked when it shipped. How long it will continue to work …. who knows …. Bob > On Nov 20, 2021, at 5:42 PM, Robert Garnett <rjg@wideband.net.au> wrote: > > Hi, > > > About five years ago I purchased a rubidium standard on eBay. It was an Efratom. Sadly although The oscillator was working but it wouldn't lock. I was comparing it to a HP Z38001A which I use as the frequency standard in my lab. > > I tried to fix it, but I couldn't find the correct schematic so I abandoned the project. > > I would like some advice on where I could get a working one and how much I should pay. > > -- > Best Regards Rob Garnett > Toongabbie Vctoria > 0351 489484 > 0417 995 247 > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com > To unsubscribe, go to and follow the instructions there.

Hi Bob, thx a lot. Now I can keep it on my list and try to get it on the second Hand market in a couple of years 😉. Its a bit too much for my hobby budget.  I am only interested in the Audio frequences below 50mhz range, so GHz is not important at the Moment for me Kind regards  Norman Gesendet von Yahoo Mail auf Android Am So., Nov. 21, 2021 at 1:05 schrieb Bob kb8tq<kb8tq@n1k.org>: Hi Rb standards have a finite life. Just how long that is depends a lot on how good a job the heatsink on them did as well as the run time. They do die of fairly normal random stuff as well. Like just about everything designed in the last 30 years, schematics and field repair manuals simply don’t exist. What to do: Start looking for shorted caps. If voltages are ok then move on to things like the frequency of the local oscillator. You can get surplus Rb’s built into functioning devices. Typical price seems to be in the $500 and up range. The advantage is that at least it worked when it shipped. How long it will continue to work …. who knows …. Bob > On Nov 20, 2021, at 5:42 PM, Robert Garnett <rjg@wideband.net.au> wrote: > > Hi, > > > About five years ago I purchased a rubidium standard on eBay. It was an Efratom.  Sadly although  The oscillator was working but it wouldn't lock.  I was comparing it to a HP Z38001A which I use as the frequency standard in my lab. > > I tried to fix it, but I couldn't find the correct schematic so I abandoned the project. > > I would like some advice on where I could get a working one and how much I should pay. > > -- > Best Regards Rob Garnett > Toongabbie Vctoria > 0351 489484 > 0417 995 247 > _______________________________________________ > time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com > To unsubscribe, go to and follow the instructions there. _______________________________________________ time-nuts mailing list -- time-nuts@lists.febo.com -- To unsubscribe send an email to time-nuts-leave@lists.febo.com To unsubscribe, go to and follow the instructions there.