[time-nuts] FE-5680A Rubidium Pinout again
jan at 41hz.com
Thu Jan 10 09:40:57 EST 2008
It's an amazing list you have here! I had no idea! A new world to me.
I am new here and this is my first posting.
I recently got one of the Ebay FE-5680A units, originating
from a Motorola telecom board, without a coax out.
I do not even have the Motorola board so there is little to
I fund some postings on the FE unit, most from 2005,
here on in the time-nuts list.
Did any of you make any progress with this unit and the
pinout and communicating with it? I'd prefer not to fry the
thing right from the start.....
I have opened the lid and found that my unit has a RS232
chip, Sipex SP233ACT. There is also a small internal
5 pin connector on the PCB, connected to the RS323
chip Rx/Tx and +5V.
I can trace the front panel 9-pin connector pin 1 / power in
to the onboard VR and pin 2 is ground.
The unit has and a AD9830A DDS for frequency synthesis.
In the product sheet for the FE-5680A it's mentioned that the
unit can be factory programmed to wanted frequency. A good
guess is that it's via this PCB port as RS232 is not available
on the front panel connector as far as I can find.
There are also two pushbuttons on one PCB.
I have seen mentioned in the datasheet that it's for trimming
Well, any input would be highly appreciated. I have searched
the net for all docs I could find but nothing very useful so far.
I will be happy to share my findings if someone is interested.
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