I have two 1992, and actually one has to terminate the output to see the real waveform. They have both the 04E option, that I believe is a nice one. In long term measurements, I've found that mine have an aging rate in the range of 1x10E-10 per day, or better (compared to Rb). The crystal is cut to 5 MHz, then doubled. The time required to stabilize after power on is normal. Antonio I8IOV
> My 1992 has a similarly ugly reference output - until I terminate it. > Then it's a fairly nice square wave between 0 and 1 volt. Rise & fall > times are in the range of 5 ns. The manual doesn't state what the wave > shape is, only that it's > 600 mVp-p into 50 ohms. I have a brochure > that says "TTL levels giving approx. 1Vp-p into 50 ohms". My phase > measurements also have a similar amount of 'noise' to yours. > > Which timebase does yours have? I've got option 4E (similar to 4B). > Although the timebase appears to be stable, I've noticed that the > counter drifts about 5e-9 during warmup, even when the oscillator has > been on standby for many days. It takes a couple of hours to settle > down. Does yours do anything similar? > > Ed > > John Green wrote: > > Just acquired a used 1992 off eBay. Excellent, almost like new with manual > > and even spare fuses. I noticed that the internal reference's waveform is > > more like a nasty sawtooth than a nice sine wave. Is that normal? Also, when > > I hook my GPSDO through a two way splitter and two different length cables > > and measure phase, I get a +\- 3 LSD ambiguity. Is that about right? > > _______________________________________________ > > 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.