[time-nuts] Special connector for Symmetricom X72 rubidium standard

Christoph Kopetzky info at cksd.de
Mon Aug 21 04:26:19 EDT 2017

Hello Ed,

No I do not want to use a printer cable to connect to the X72 
oscillator. This is not recommendable as you wrote for several reasons.
I would prefer a solution which uses an actual connector which could 
replace the obsolete Molex 52660-2651 plug.
This is very difficult because every manufacturer which had connectors 
with 1.0 mm pitch in its program has stopped production of those connectors.
I wrote a lot of emails the last days to a lot of sellers and to 
manufacturers which had 1.0 mm pitch conns in their program but all 
cannot sell ones right now.
Another solution would be to to replace the original Molex board 
connector with a newer 1.27 mm pitch one. There a some sources but it is 
hard to find one which fits the onboard pcb layout. So I do not want to 
rebuild the X72. I prefer a solution which do not modify the rubidium 

Mark Sims solution to build a new connector board with the needed 
connections and may be a little bit more features will be the best 
solution right now. So if he had finished his board I would be happy to 
get the sources to get some ordered at my local PCB manufacturer.
I think that brings the best options for future use of the X72 
oscillator which seems to be a very good small rubidium oscillator 
nowerdays. SA22.c oscillators are not so spread over the known used-item 
reseller sources and if yes they are quite expensive to buy.

If some of you wants to buy one ore more X72 I had a link to a seller 
which has a few on stock:
Here is the link:

Have a nice day and

*with best Regards*

> Chris,
> Are you suggesting reusing the entire cable?  I wasn't suggesting that.
> The cable is over a meter long!  Even if the wiring was correct, which
> it isn't, I don't know if you could pull enough power through those 28
> guage wires even though they have multiple leads in parallel.  Either
> remove the cable from the IDC connector and replace with something more
> appropriate or cut the cable and leave maybe 10 cm. of cable attached to
> the connector.  Terminate as appropriate.
> Datum understood that different situations require different solutions.
> They provided both Molex and 'circuit board' connectors for maximum
> flexibility.  Personally, I think the connector looks a little silly.
> It's so big compared to the X72.  But for some users, it might be perfect.
> I'm looking forward to Mark's circuit boards.  I have one of the
> official boards that I've barnacled a few extra leads onto to bring out
> the signals that Datum didn't, but it's ugly.  A better solution would
> be welcome.
> You asked for the connector, I provided a source.  As is typical with
> Time-Nuts equipment, some assembly is required.
> Ed
> On 2017-08-18 9:56 AM, Christoph Kopetzky <ck at cksd.de <https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts>> wrote:
> >/Hello all, />//>/here is the connection schematics from symmetricoms designer manual for />/the X72. />/So you see, that there is no need for an25 pin connector on the boards />/side:) />//>//>//>/If someone wants to download the X72 designer guide here it is: />//>/http://www1.symmetricom.com/media/files/support/productmanual/man-x72.pdf 
> />//>/Regards />//>/Chris /

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