Me too, please.
-Brian, WA1ZMS -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Sunday, August 12, 2012 2:55 PM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] FRK specs..... Bert: Interesting. I, too, have a couple of the HP 10811 oven-oscillators sitting on the shelf for several years, ....waiting for a project. I want to 'discipline' them, but really do not know how. Could you kindly mark up the HP 10811 schematic and/or please tell me what to cut, ... what to jumper??? Thanks a lot! Don Lewis Austin, TX ---------------------------------------------------------------------------- -- ================================================== ---- [email protected] wrote: > In the commercial world a PRS10 is most likely the best but for time > nuts even at the surplus price in my opinion it is all hype and a > waste of money. Have you looked closely at the specification and the > design. Frequency accuracy can not be better than 1 E-12 since the > OCXO is driven strictly by a DAC and the A/V is for time nuts nothing > to write home about. Any digital loop controlling a Rb in tern with an > analog loop controlling a selected HP 10811 or for that matter a Morion will outperform a PRS 10. > I have a FRK-H controlling a HP 10811 that has an A/V below 1 E-12 > from 1 to 100 seconds, I modified the FRK loop and the 10811. On the > 10811 it is easy to get to the bottom PCB and without un soldering any > component or further disassembly cutting two traces and two jumpers > you end up with a 2 to 12 Volt tuning voltage, perfect for a FRK or > M100.. A second option is to use a separate analog loop with a time constant suitable for your OCXO. > By the way the FRK-H is not lower noise but factor 2 lower aging with > the proper OCXO not an issue, since hopefully you discipline it with GPS. > For 12 years I have used Shera in that application recently switching > the DAC to a LTC1655. Has served me well over the years. > Other Rb's will do also a very credible job. On one extreme a FEI 5680 > is waiting to be integrated with a MV180 on the other extreme a HP5065 > RVFR assembly will be integrated with a M1000 OCXO along with state of > the art circuitry. > Bert Kehren > > > > In a message dated 8/12/2012 8:09:54 A.M. Eastern Daylight Time, > [email protected] writes: > > Thanks Tom. > > I agree, the SRS seems to be the best > overall Rb except maybe on old HP if one is willing to spend about the > same price on a 20 year old unit. The SRS units I bought for work were > only > $2700 with chassis, rack ears and multiple outputs. > > > > -Brian, WA1ZMS > > On Aug 12, 2012, at 3:17 AM, Tom Knox <[email protected]> wrote: > > > > > Hi Brian; > > There are a few decent rubidium oscillators short term like the SRS > > but > none are great, in my humble opinion you are much better off > disciplining a good quartz oscillator off your LPRO. > > Best Wishes; > > Thomas Knox > > > > > > > >> From: [email protected] > >> Date: Sat, 11 Aug 2012 21:56:13 -0700 > >> To: [email protected] > >> Subject: [time-nuts] FRK specs..... > >> > >> I used to be of the opinion that the Efratom FRK-H was the best of > >> the > models of FRK Rb standards for both short-term stability and overall > performance. > >> > >> Is that still true today? > >> > >> I know there are better solutions for short-term (BVA OCXO) and > >> long > term > >> (Cs & MASERS). But where to things stack up today? > >> > >> I'm looking to buy an Rb that's better than my LPROs and other models. > >> But I do not own an FRK-H. > >> > >> Looking for comments, please. > >> > >> Thanks in advance, > >> -Brian, WA1ZMS > >> _______________________________________________ > >> time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > >> and follow the instructions there. > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
