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

[Bob kb8tq]

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
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