The phase plots on tvb's web site http://www.leapsecond.com/pages/tadd-1/3phase2.gif show that the device's temperature was never stabilized. The closest to being stable is at the 29 minute point on that plot.
Particularly when the phase value goes up (not sure if it's when temperature goes up or down), because the phase was still changing at a pretty high rate when the compressor changed state. I think Tom should rerun that test with a much slower cycling, to make sure the phase was stable before the compressor was turned on (or off). Since the phase excursion was not complete, the 150pS/degree is probably underestimated. My guess is that the period should be at least doubled. Didier KO4BB > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Jeff Mock > Sent: Friday, March 28, 2008 12:29 AM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] TADD-1 six channel RF distribution amplifier > > > Bruce Griffiths wrote: > > Steve wrote: > >> I'm thinking about using the TAPR TADD-1 six channel RF > distribution > >> amplifier to distribute the 10MHz output of my Trimble > Thunderbolt to > >> a few pieces of test equipment. > >> > >> What does the TADD-1 do to the phase noise characteristics of its > >> outputs as compared to the phase noise characteristics of > its input? > >> Improve? Degrade? Little or no change? > >> > >> Thanks. > >> > >> Steve K8JQ > >> > > I've been using a TADD-1 for about 6-months now and I'm quite > happy with it. You certainly can't beat the price. I added > the optional 10MHz BPF and tuned it with a tracking generator > and spectrum analyzer. The outputs are very clean. > > I've never tried to measure phase noise, but the op amps and > the rest of the circuit seem to be good choices to me. tvb > did some analysis of the box you might find interesting: > http://www.leapsecond.com/pages/tadd-1/ > > jeff > > > _______________________________________________ > 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. > > No virus found in this incoming message. > Checked by AVG. > Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release > Date: 3/22/2008 4:43 PM > > No virus found in this outgoing message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.21.8/1339 - Release Date: 3/22/2008 4:43 PM _______________________________________________ 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.