[time-nuts] Re: Some assistance with Ball-Efratom FRK-L Rb Osc. Needed

[paul swed]

As Bob says you can use an internal or external supply and 10K pot to
ground or leave open.
With respect to the internal regulator. I think there are two things at
startup: the voltage is higher and drops after ignition. So go with the 24V
supply about 2 amps should work and to some extent that will drop some
generated heat. But most RBs simply have to run hot due to the ovens in
them. Add a good heatsink. Suspect the manual says that.
Good luck Walter.
Paul
WB8TSL

On Tue, Sep 21, 2021 at 8:02 PM Bob kb8tq <kb8tq at n1k.org> wrote:

> Hi
>
> The “normal” FRK-L is the low phase noise version of the FRK.
> There are two “external control” options. One is a 10K pot the
> other is a EFC voltage. Simple answer is to short the wires / leave
> them open.
>
> The big deal is finding out if the beast still locks and how much
> signal is getting to the photo diode.
>
> Bob
>
> > On Sep 21, 2021, at 7:50 PM, Walter Shawlee 2 <walter2 at sphere.bc.ca>
> wrote:
> >
> > I just stripped one of these units out of an Argo Systems AS-210 to use
> as a stand alone reference.
> > The system ran before I did this, so I was sure all the hardware was
> working.
> > It is marked FRK-L (manual says this the low temp operating version),
> and says
> > Efratom p/n 2A5A2A.  I did not see any data in the factory manual for
> what this might mean,
> > but it has the coax 10MHz, and pins for #2-9 connections.
> >
> > My issue is that this has wires attached to pins 8 and 9, the *optional
> remote frequency adjustment.
> > The label says "Unit Wired For Operation With External Frequency
> Control".
> > *This is discussed *nowhere* in the 79 page manual, and I have no idea
> what to do with these connections.
> > the option is listed as a possible one, but nothing further is said, and
> no connections to it show up anywhere.
> >
> > Any information is very welcome, as I would like to make a back up Rb
> standard for my bench and this
> > looks like a great candidate if I can get it running.
> >
> > Also, from a waste heat viewpoint, the supply range is 22-32VDC, the
> schematics discuss an internal +17VDC bus,
> > so am i correct in thinking that a well regulated +22-24VDC supply is
> better than a +28VDC one in terms of waste heat (and shortened life)?
> >
> > many thanks,
> > walter
> >
> > Walter Shawlee 2
> > Sphere Research Corp. 3394 Sunnyside Rd.
> > West Kelowna, BC, V1Z 2V4 CANADA
> > Phone: +1 (250-769-1834 -:- http://www.sphere.bc.ca
> > +We're all in one boat, no matter how it looks to you. (WS2)
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> >
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