Bryan, I also found a stable 30MHz which I think is used to clock the optional DDS board so I intend to experiment adding an AD9851 board with 6x multiplier enabled but first I want to try and understand why the unit locks and only outputs 10MHz from the XC9572, something in the firmware appears to turn off the output, I may get around to experimenting a little more soon and will of course share my findings if they're of interest. .
Bob, there are files which claim to be a dump of the firmware and also the XC9572 along with a partial schematic but they're from a 5680A which, from the pictures on the net, is a slightly different hardware version although the major components appear identical so it may be possible to modify the B version Bryan and I have. On 26 September 2015 at 02:45, Bryan _ <[email protected]> wrote: > There is information on this thread on how you can tap into the unit at > various points to get 20 and 60Mhz. Other owners have used a divider to > bring it to the 10Mhz frequency desired. I have one of these units and > haven't gone around to dividing it down. I purchased mine from Ebay and the > seller notes that this particular version will output 10Mhz for a second or > two and then disappear. I suspect you have the same version, maybe even the > same seller, so the operation of these particular units appears to be > normal. Mine will lock so I know it's working. > > http://www.eevblog.com/forum/testgear/fe-5680b-1pps-to-10mhz/msg556800/#msg556800 > I as well wish there was a quick way of converting it back to 10Mhz. I am > sure it can be done, just not sure how or where to look <g> > > -=Bryan=- > > > From: [email protected] > > Date: Fri, 25 Sep 2015 17:45:08 -0400 > > To: [email protected] > > Subject: Re: [time-nuts] FE-5680B Rubidium and DDS > > > > Hi > > > > There is no dump of the firmware. The problem you are most likely > > having is not firmware related. > > > > If the VCXO i the unit drifts to far it needs to be re-tuned. Until this > is done > > the device simply sits in a “search for lock” loop forever and ever. > > > > Simple way to do it: > > > > Monitor the VCXO and bump the trimmer until the frequency goes above the > intended > > target (10 x N MHz depending on your monitor point) by at least 0.15 > ppm. The sweep is > > slow enough that a counter running at a 0.1 second gate will easily show > you what’s going on. > > > > Of course it can be other things. All of them are a bit more involved to > fix. > > > > Bob > > > > > On Sep 25, 2015, at 11:34 AM, Clint Jay <[email protected]> wrote: > > > > > > I've recently purchased one of the PPS Only FE Rubidium standards from > eBay > > > and, like many others I suspect, haven't been able to get a stable > output > > > frequency that lasts longer than a few seconds from the module. > > > > > > It appears that the 10MHz source vanishes after a few seconds but this > is > > > controlled by firmware. > > > > > > Which leads to my question, there is a dump of the firmware from the > > > FE-5680, has anyone tried to reprogram one? > > > -- > > > Clint. > > > > > > *No trees were harmed in the sending of this mail. However, a large > number > > > of electrons were greatly inconvenienced.* > > > _______________________________________________ > > > time-nuts mailing list -- [email protected] > > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > and follow the instructions there. > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > and follow the instructions there. > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. > -- Clint. *No trees were harmed in the sending of this mail. However, a large number of electrons were greatly inconvenienced.* _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
