[time-nuts] problem with Efratom FRS-C from eBay

Robert Darlington rdarlington at gmail.com
Sat Oct 18 03:40:35 UTC 2008


I got it, it's working (and it always was).   Reading the manual I see that
the lock signal can either be high or low depending on how some jumpers are
set on the servo board.  I unplugged the supply, disconnected the connector,
and added proper lines to my meter while the unit cooled off a bit and
rested.  A few minutes later with everything connected I plugged it in.  5
volts out of the lock line was present while the system hunted.  A couple of
minutes later and the frequency counter stabilized and the meter went to
0.02 volts.   The voltage on the lamp monitor is reading 8.78 to 8.79
volts.  Stabilized is relative, and if this thing had more digits, I'd like
to think that I'd have a few more not moving.

Thanks for helping out guys.  I really appreciate it.

On Fri, Oct 17, 2008 at 4:47 PM, Robert Darlington <rdarlington at gmail.com>wrote:

> Hello all,
>
> My FRS-C showed up today.  I carefully wired it up and powered it on.  I
> got a nearly 10MHz signal out.  The frequency counter is dancing around a
> bit and I get a 0.02 V on the lock indicator line after about an hour warm
> up.  Specs show this should happen in under 10 minutes and it looks like it
> is not locking.   Dead unit?
>
> I obtained it from this ad:
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290262243079
>
> The unit that I received does not show TTL after the frequency and the
> scope output looks like a cross between a sinewave and a ringing square
> wave.  I have about 13 feet of RG174 between the FRS and the measurement
> equipment so who knows.   This is the "*Rubidium and GPS DO From China<http://stores.ebay.com/Rubidium-and-GPS-DO-From-China>"
> *eBay store, which I thought was pretty reputable so I want to make sure
> I'm not doing anything wrong before I contact the seller, PayPal, etc.*  *There
> was also a big white sticker covering the whole top of the unit.  I had to
> remove it to verify the pinouts and the model information.  Hoepfully that
> didn't void my warranty on the $100 paperweight.  Should I let it sit
> overnight?  Any suggestions would greatly be appreciated.
>
> Thanks,
> Bob, N3XKB
>


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