Jerry, Do you have a heat sink mounted to the Rb source ? It sounds, possibly, like a heater not reaching equilibrium.
Didier's suggestion of comparing against WWV would be a good start to find who is at fault. Your counter time base may have an unknown problem. Bill....WB6BNQ Didier Juges wrote: > Jerry, > > 80 Hz is much more than either device should exhibit. There is something > seriously wrong, and if you have a short wave receiver that can receive > WWV at 10 MHz (AM is fine), you should try to listen to the beat > frequency between WWV and either oscillator. That will tell you which is > off. > > You may have to use a small piece of wire plugged into the BNC of either > oscillator as an antenna. adjust the length and/or separation with your > receiver to adjust the level so that you hear a beat frequency with WWV. > > Alternately, try to borrow a known good counter from someone local. In > either case, an oscilloscope would help check the outputs. When an > oscillator is way off in frequency, the signal may not look right on the > scope. > > Didier > > JOS Earthlink wrote: > > Hi Group, > > > > I'm a newbiew and just bought a Lucent RFG-RB rubidium source on Ebay from a > > reliable seller. I am observing a daily variability of about 80Hz and > > hourly variability of a few Hz with a calibrated HP 5334B counter (with oven > > oscillator option). The counter and rubidium source have been powered on > > for over a week in my basement workgroup which has a stable ambient > > temperature. I'm using a cannnibalized power supply from an HP-5328A (all > > the caps replaced) for the 24v rubidium power source ... its supposed to be > > a quite stable PSU. > > > > Is this variability more likely due to the rubidium source (failing bulb) or > > due to problems with the 5334B counter? > > > > Any advice appreciated. > > > > Jerry > > K1JOS > > > > > > _______________________________________________ > > time-nuts mailing list > > [email protected] > > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > > _______________________________________________ > time-nuts mailing list > [email protected] > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
