Despite what has been previously posted I’ve found my 565s to be very good frequency references for my counters and they seem to compare well to the Thunderbolts. I haven’t run any long term checks but comparing Tbolts to 565s on my scope from time to time I’ve never seen any jumps or significant frequency drift (at 5ns/cm). The 565s generally report parts in E-12 to E-14 depending on conditions.
In regard to replacing the crystal oscillator with a rubidium, I tried that once using an X72 and wasn’t impressed. It worked o.k. but as you can see from the manual specs below the only gain would be during long periods of signal loss or ‘coasting’. As long as you have a signal the average accuracy will be the same and I feel the OCXO could possibly be a little less noisy and perhaps have better short term stability although I never checked it. -Arthur 565 (High Performance Quartz) Accuracy Error Time Locked................................1 X 10-12 (1 day average) Coasting..................................... 5 X 10-10/day (Rubidium) Accuracy Error Time Locked................................1 X 10-12 (1 day average) Coasting..................................... 2 X 10-11 /day _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
