Jim Williams wrote an appnote on how to do this with ~100ps resolution with a small number of parts. I think it was mentioned before and should be in the time nuts archives.. His circuit can be modified without much effort for higher resolution. bye, Said In a message dated 3/21/2012 14:03:38 Pacific Daylight Time, lists@rtty.us writes: Hi Ok, for a legit 12 ps with 0.1 ps drift and 200 mega samples per second - not to many alternatives. The FPGA stuff will get you to 50 to 100 ps on the same basis this gets you to 12 ps. They will get you to 20 to 40 ps on a good day - sort of the way this chip gets 8 ps. The FPGA will do it at a much lower data rate. If you average over many samples, all of these will get you a better estimate. How much better depends on a bunch of things. The TI part *could* do very well if you have a 200 MHz signal to look at. Bob -----Original Message----- From: Ben Gamari [mailto:bgamari@gmail.com] Sent: Wednesday, March 21, 2012 3:30 PM To: Bob Camp; 'Discussion of precise time and frequency measurement' Subject: Re: [time-nuts] Experience with THS788 from TI? Bob Camp <lists@rtty.us> writes: > Hi > > Are you after 12 ns or 12 ps? > Bah, yes, my bad: picoseconds is the relevant timescale here. Cheers, - Ben _______________________________________________ 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.