Hi: WOW! I've got s/n 1227 to parts in E-14 and think I'm within one C-field tick of getting it as good as the factory step sizes allow. Now at 492 on the thumb wheels and maybe 491 would be better. Also s/n 1013 that I thought had a bad C-field adjustment was just way off in it's C-field setting. The optimum setting remains to be seen but when at 909 it's within parts in E-13 of s/n 1227. This is being measured by using the 1 MHz out of both sources and feeding that into the start and stop inputs of an HP 5345 counter.
The thing that has made all the difference is feeding the cesium output to the SR620 10 MHz rear panel Reference input and taking the front panel 1 kHz reference output and using that instead of the 1 Mhz from the standard for the stop signal. By dividing down the noise is reduced radically. I'm now seeing 500 second averages that typically differ by a couple hundred pico seconds. When I was using the cesium 1MHz as the stop input adjacent 500 second averages might differ by up to 8 nano seconds. Having Fun, Brooke -- w/Java http://www.PRC68.com w/o Java http://www.pacificsites.com/~brooke/PRC68COM.shtml http://www.precisionclock.com _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
