Re: [time-nuts] AN/URQ-10A frequency standard
Thank you for you replies Dave and Paul! Well, patience won out and I left the unit on for a considerably longer time. The inner oven meter indication then started to come up off of zero after nearly seven hours. Not knowing the thermal mass it has to heat I guess I assumed that it would have a slightly quicker response time. My ignorance... This morning I checked the unit again and the inner oven indication is slightly lower than where it should be in the red OK region on the meter meaning that the heater is still delivering a little more than normal heat and the 5 MHz frequency, which started out at ~+33 Hz cold, is now at -1.2 Hz and holding steady telling me that the heat delivered has overshot its normal operating point. Granted I have not let the crystal assembly soak for any considerable time but my mind is thinking about a possible bias in the heater control circuit by a leaky passive component or transistor causing it to remain on a little more than necessary. But, again, I will be patient and watch its progress over the upcoming days. I pulled out a Sulzer 5A manual and took a closer look at the schematic. From what I observed in the URQ-10 circuitry that is external to the FE-10 oscillator itself, the power supply and frequency handling portions appear to come close to nearly a carbon copy of the older Sulzer unit. The non-A version URQ-10 design is considerably different and somewhat more complex. And if anyone out there comes across an A version manual or has one in their possession, I would be willing to compensate them for a photocopy. Regards, Greg ___ 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.
Re: [time-nuts] AN/URQ-10A frequency standard
I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL On Sat, Apr 27, 2013 at 12:21 PM, Gregory Muir engineer...@mt.net wrote: Thank you for you replies Dave and Paul! Well, patience won out and I left the unit on for a considerably longer time. The inner oven meter indication then started to come up off of zero after nearly seven hours. Not knowing the thermal mass it has to heat I guess I assumed that it would have a slightly quicker response time. My ignorance... This morning I checked the unit again and the inner oven indication is slightly lower than where it should be in the red OK region on the meter meaning that the heater is still delivering a little more than normal heat and the 5 MHz frequency, which started out at ~+33 Hz cold, is now at -1.2 Hz and holding steady telling me that the heat delivered has overshot its normal operating point. Granted I have not let the crystal assembly soak for any considerable time but my mind is thinking about a possible bias in the heater control circuit by a leaky passive component or transistor causing it to remain on a little more than necessary. But, again, I will be patient and watch its progress over the upcoming days. I pulled out a Sulzer 5A manual and took a closer look at the schematic. From what I observed in the URQ-10 circuitry that is external to the FE-10 oscillator itself, the power supply and frequency handling portions appear to come close to nearly a carbon copy of the older Sulzer unit. The non-A version URQ-10 design is considerably different and somewhat more complex. And if anyone out there comes across an A version manual or has one in their possession, I would be willing to compensate them for a photocopy. Regards, Greg ___ 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.
Re: [time-nuts] AN/URQ-10A frequency standard
On Sat, 27 Apr 2013 16:16:17 -0400, Paul Swed wrote: I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL These are neat little machines. But this one is still sticking to it's abnormal inner oven temp and is not moving. I'll let it cook a little longer then may have to do some invasive diagnostics. I keep an odd assortment of whatever-I-can-find oscillators around the lab for use as external time base clocks for frequency counters that I use to look at frequency offsets in stabilized light sources by heterodyning their outputs against a calibrated optical source to generate more easily measured RF products in the microwave range. I'm hoping this little guy will start to show its stuff soon. Greg ___ 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.
Re: [time-nuts] AN/URQ-10A frequency standard
Gregory Well I am afraid I have become spoiled in that I use the GPS locked references these days. They consume little power or maybe about the same actually as the 10. So I also have a mix of great old oscillators. But for me at least thats what the 10 would be. I have to say that it was what started me on the ole time-nuttery way back when I had to adjust our shipboard radios to the reference incase they ever failed or... Though at that point I don't think radios would have been on my mind. I had looked for them at hamfests over the years the closest I came was some apha grade urq 11,12, or 13 from Frequency Electronics. Anyhow its never ever worked right at the core. And thats why it was at the hamfest. I did not pay much for it so can't actually complain. You don't really see much of that stuff anymore. Good luck on the inner oven. Regards Paul. On Sat, Apr 27, 2013 at 8:33 PM, Gregory Muir engineer...@mt.net wrote: On Sat, 27 Apr 2013 16:16:17 -0400, Paul Swed wrote: I looked and must have hit the same site you did for the sulzer. Yes I expect a log warmup. I used them in the navy and we never let them go cold. circa 1973-1979. Took them to the cal lab on battery etc. I thought maybe I would have a manual I don't. You are lucky to get one. Great reference. I do have two model 5a sulzers. I actually use one to generate the lab frequencies for stuff. I really should put it back together which I can do and just create a more modern divider. That would consume less power and be equally clean also take less space. 1 RU. Regards Paul WB8TSL These are neat little machines. But this one is still sticking to it's abnormal inner oven temp and is not moving. I'll let it cook a little longer then may have to do some invasive diagnostics. I keep an odd assortment of whatever-I-can-find oscillators around the lab for use as external time base clocks for frequency counters that I use to look at frequency offsets in stabilized light sources by heterodyning their outputs against a calibrated optical source to generate more easily measured RF products in the microwave range. I'm hoping this little guy will start to show its stuff soon. Greg ___ 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.
