> A guy by the name of David W. Allan used direct multiplication to > build NBS-4 and NBS-5, see http://tf.nist.gov/general/pdf/65.pdf . He > didn't see anything wrong with it. He used a commercial frequency > standard modified from 5 mc to 5.006880 mc.
That kind of LO is ok for a research clock. But maybe not so good for a working institutional or house standard where people expect frequency distribution in nice round numbers like 5 or 10 or 100 MHz. The good news is that you can get a perfect 1PPS out of it: divide by 5006880 = 2^5 * 3^3 * 5 * 19 * 61. I've heard JohnA has one of these vintage 5.006880 mc oscillators so I did a PIC divider for him. See pd21 under www.leapsecond.com/pic/src/ /tvb _______________________________________________ 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.
