Hi Bob I will enquire of a friend. I would not be surprised if they were in house manufacture they were used for a very long epriod without changes in "design". There is a history of UK firms making their own OCXOs .....Pye, Marconi, etc. Racal had a big investment in frequency determination for most of their output went to the military. There are sophisicated standards and Rubidiums in their catalogue. Most of the OCXO (quartz crystal specialist) makers in the UK finished them is sealed cans. Racal were of course the parent of Vodaphone and made a lot of their original site hardware.
Alan G3NYK ----- Original Message ----- From: "Bob Camp" <li...@rtty.us> To: "'Discussion of precise time and frequency measurement'" <time-nuts@febo.com> Sent: Thursday, August 25, 2011 5:01 PM Subject: Re: [time-nuts] Racal 9420 OCXO > Hi > > Do we know for sure that Racal actually made these OCXO's in house? > > My *guess* is that they were made by various companies over the years and > sold to Racal. The "return for service" would have been a return to Racal > and then they forward it to the people who made it... > > Bob > > -----Original Message----- > From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com] On > Behalf Of paul swed > Sent: Wednesday, August 24, 2011 5:10 PM > To: Discussion of precise time and frequency measurement > Subject: Re: [time-nuts] Racal 9420 OCXO > > Kind of amazing what time-nuts have in there secret documentation. > Though I do not need this thanks for sharing. > Regards > Paul > WB8TSL > > On Wed, Aug 24, 2011 at 4:05 PM, Robert Atkinson > <robert8...@yahoo.co.uk>wrote: > > > Hi, > > I've attached a copy of the catalogue specification for Racals OCXOs. They > > do have electronic trim as standard. They are used in the 9478 frequency > > standard. The 9478 service manual specfically states that no information > on > > the OCXOs is provided and they must be returned to Racal or appointed > agents > > for repair. > > > > Robert G8RPI > > > > --- On Wed, 24/8/11, gandal...@aol.com <gandal...@aol.com> wrote: > > > > From: gandal...@aol.com <gandal...@aol.com> > > Subject: Re: [time-nuts] Racal 9420 OCXO > > To: time-nuts@febo.com > > Date: Wednesday, 24 August, 2011, 16:03 > > > > In a message dated 24/08/2011 00:03:19 GMT Daylight Time, > > dan...@verizon.net writes: > > > > I don't think Racal released circuit diagrams of any of their ovens. I > > have traced out the circuit of the rapid warm up oven found in a lot of > > receivers, the 9442-12 and have fixed those, there is a ceramic cap that > > frequently goes wonky. The two 9420s I have fixed were just broken > > wires; they seem to have used PVC insulated wire which degrades... I > > haven't done the homework on those yet. > > > > The 9420s I have do have an EFC input as well as a stabilised Voltage > > out to feed it, and in the receivers I have that use it [RA1795] the > > fine setting is done from that, coarse setting from the top adjustment. > > ------------------------- > > Hi Dan > > > > I've taken a further look at the RA1794 manual and see now that it does > > confirm a fine tune pot being available when using the 9420. > > Having opened up this oscillator I find there are connections to every > pin > > on the B7G connector so will assume until proven otherwise that it does > > meet the interface spec shown in the 1794 manual. > > I suspect the comments I've seen claiming most do not have the EFC option > > is more a case that in many installations it isn't used, which isn't > quite > > the same thing. > > > > Thanks again for your comments. > > > > regards > > > > Nigel > > > > > > _______________________________________________ > > 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. > > > > _______________________________________________ > > 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. > > > _______________________________________________ > 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. > > > _______________________________________________ > 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. _______________________________________________ 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.
