I'll second the PRS-10, I have a used unit that I am very happy with. My only complaint is that a few times an hour it fails to produce a PPS. On my unit I expect that the problem is that it is going out of lock (used!!!).
--mike On Wed, Jul 21, 2021 at 4:04 AM Dana Whitlow <[email protected]> wrote: > Bert, remember that I need a very long locking loop time constant setting > in > order to smooth out GPS noise, so in a sense the GPSDo is *almost* in a > holdover state anyway, all the time. > > Probably the smartest thing for me to do is to buy a spanking new PRS-10, > with the PPS locking feature present. Then I could just leave it locked to > GPS most all the time, but disconnect the PPS and let it go into holdover > on the rare occasions when I need a few hours of even better stability. > > Dana > > > On Tue, Jul 20, 2021 at 6:56 PM ew via time-nuts <[email protected] > > > wrote: > > > There is a lot of misinformation out there. It is not the OCXO that > > changes, Bruce did extensive testing and I did some too. The Vectron is > > super, would like to know what is in it but do not want to open one. Once > > warmed up the stable OCXO temperature is a main contributor to the board > > temperature. Using a Dual Oven may give you a warm feeling but only adds > 1 > > more Watt of stable heat to the board making the temperature change > > smaller. The OCXO is important during Hold Over and that is why it is > > there. The changes are the DAC which is updated once a second. Very > > temperature sensitive. Cheap. We have done the tests 10811, OSA 8600, > FRK > > and M100. For fun did use a cheap small OCXO, no performance change. Was > > done in Juerg's temperature stable basement. See attached picture. > > > > Bert Kehren > > My experiences with the T'Bolt have not been entirely satisfactory. If I > > set the loop > > lime constant long enough to get a satisfying smoothing of the GPS noise > (a > > few hundred > > seconds), then the thermal sensitivity of the VCXO on the T'Bolt rears > its > > ugly head and > > I see a lot of my HVAC system cycling instead. The T'Bolt E supposedly > has > > a double- > > oven XO, so I'd like to give that a try. But my wallet says "whoa"! > > > > According to Bodnar, his units do have some choices in the time constant > > setting. > > I've been considering ordering a Bodnar just for frequency agility, but > > have been > > holding off out of concern for the complications of dealing with a > foreign > > supplier. > > > > Dana > > _______________________________________________ > > time-nuts mailing list -- [email protected] -- To unsubscribe > send > > an email to [email protected] > > To unsubscribe, go to and follow the instructions there. > _______________________________________________ > time-nuts mailing list -- [email protected] -- To unsubscribe send > an email to [email protected] > To unsubscribe, go to and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] -- To unsubscribe send an email to [email protected] To unsubscribe, go to and follow the instructions there.
