Thanks Alan, just what I wanted! J. On 16 Nov 2011, at 22:58, Alan Melia wrote:
> Hi John the attached is out of a 1987 catalogue. > Alan > G3NYK > > ----- Original Message ----- > From: "John Howell" <[email protected]> > To: "Discussion of precise time and frequency measurement" > <[email protected]> > Sent: Wednesday, November 16, 2011 9:49 PM > Subject: Re: [time-nuts] Racal-Dana 1992 Startup -- GPIB! > > >> Robert, >> Do you have any information as to where a 9421 stands in this regime, > specs etc? It is the same size as the 9420 and has a doubler board attached, > but I don't know what equipment it was used in. >> Regards, >> >> John H. >> >> >> >> On 16 Nov 2011, at 19:56, Robert Atkinson wrote: >> >>> These counters used Racal's own 94xx series OCXO's. The 04A normally had > a 9442, the 04E had the 9420. Easy way to tell which is which is the size. > They are both 51mm (2") square with the 9442 being 51mm tall and the 9420 is > 96mm (3.75") tall. The 9442 is also classed as fast warm-up, 6 minutes to > 3x10^7. >>> >>> These OCXO's were also used in Racal's frequency standards such as the > 9478. They are very good OCXO's. All of them are 5MHz. Unfortunatly Racal > considered them propriatry and never released any circuits or service > information. >>> All my information comes from Racal manuals and the 1984/85 catalogue. >>> >>> Robert G8RPI. >>> >>> >>> >>> ________________________________ >>> From: Larry McDavid <[email protected]> >>> To: Robert Atkinson <[email protected]>; Discussion of precise time > and frequency measurement <[email protected]> >>> Sent: Wednesday, 16 November 2011, 18:25 >>> Subject: Re: [time-nuts] Racal-Dana 1992 Startup -- GPIB! >>> >>> There are other Racal timebase options as well. >>> >>> I have a Racal 1999 counter that originally had a 04C timebase option > that was not ovened and had a single adjustment screw. I replaced it with a > 04A ovened ocxo that has a single adjustment screw. I will shortly install a > 04E ocxo as Robert describes below. There is also a 04B ocxo option with two > adjustment screws (coarse and fine). All the specs are slightly different. > My manuals do not show a 04T option. >>> >>> There is also a Rb oscillator option, 04R. I've never seen one of these. >>> >>> None of these is necessarily on frequency! You must have something like > a GPSDO that outputs 10 MHz to set any of the timebase options accurately. > Accuracy is relative, of course! >>> >>> I use a HP Z3801A GPSDO and a TAPR distribution amplifier to distribute > the GPS-steered 10 MHz to numerous devices that accept an external timebase, > such as the Racal counter. >>> >>> It's a very nice counter. >>> >>> Larry W6FUB >>> >>> >>> On 11/16/2011 10:02 AM, Robert Atkinson wrote: >>>> Hi Chuck, >>>> You need to look at the option sticker on the back of the unit. The 04* > is the oscillator option. >>>> >>>> 04T is a TCXO 3x10^7 per month& temp1x10^6 0-40 deg C >>>> >>>> 04A Ovened oscillator 3x10^9 per Day& temp3x10^9 0-45 deg >>>> >>>> 04E High stability ovened oscillator 5x10^10 per day& temp7x10^9 0-50 > deg C >>>> No 04* is basic crystal oscillator. If yours has a mechanical and > electrical trim it will be a 04A or 04E. >>> ... >>>> >>>> ________________________________ >>>> From: Chuck Forsberg WA7KGX N2469R<[email protected]> >>>> To: time-nuts<[email protected]> >>>> Sent: Wednesday, 16 November 2011, 16:47 >>>> Subject: [time-nuts] Racal-Dana 1992 Startup -- GPIB! >>>> >>>> I found a use for the GPIB interface on my counter - record >>>> the frequency drift of its internal timebase during warm up. >>>> It looks like an oven warming up. I don't know exactly which >>>> timebase my 1992 has, but I did notice the 5 to 10 MHz doubler >>>> on the back of the oscillator, The back has separate coarse >>>> and fine frequency adjustments. Can someone identify which >>>> timebase is fitted to this counter? >>>> >>>> The link below has the story and plot. >>>> >>>> http://www.omen.com/ham/racal.html >>> ... >>> -- Best wishes, >>> >>> Larry McDavid W6FUB >>> Anaheim, CA (20 miles southeast of Los Angeles, near Disneyland) >>> _______________________________________________ >>> 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. > <racalosc.pdf>_______________________________________________ > 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.
