[time-nuts] Ebay FE-5680A Rb I see the price has gone up for these
quenbob5 at pacbell.net
Tue Dec 20 13:46:38 EST 2011
I also got an FE5680A, what a deal. Thanks to earlier postings I had the
correct pin out, info on the 1/16 hex key and the command set. It needs 5V
on pin 4 to operate.
After 24 hours mine ran 6 mHz low compared to my GPS-based 10 MHz.
I opened the case by removing the 2 flat head screws near the connector and
the 2 pan head screws in recesses in the center of the base plate. I
noticed what looked like smoke residue from a blown part, as have others,
but no sign of a bad part.
The LPRO-101 has a flat surface and a thermal pad for heat transfer over the
whole base. The FE-5680A injects heat into the base plate in the center and
sinks it around the edges. Good magnetic shielding and thermal transfer may
require using most of the 16 mounting holes.
I found "Termite 2.7" from CompuPhase worked to communicate with the
FE-5680A in Windows. I set the COM port, 9600 baud, local echo, append
nothing and hex view. I sent 0x2D040029 to get the offset. The "0x" lets
the program know the number is in hex. My offset was 0, same as others have
mentioned. Possibly the FE-5680 was controlled externally to sync up the
1pps output to GPS using the "set temporary offset" command.
I wonder if there's a status command, analogous to the lamp voltage test
point on the LPRO-101.
From: Chuck Forsberg WA7KGX N2469R
Sent: Monday, December 19, 2011 2:25 PM
To: lists at lazygranch.com ; Discussion of precise time and frequency
Subject: Re: [time-nuts] Ebay FE-5680A Rb I see the price has gone up for
My 5680A arrived today. Mailman demanded a signature.
This thing requires plenty of current to get started.
My Tek CPS250 1.2 amp output (A+B parallel) only gets 7.5 volts.
Now to scrounge something a bit bigger.
Chuck Forsberg WA7KGX N2469R caf at omen.com www.omen.com
Developer of Industrial ZMODEM(Tm) for Embedded Applications
Omen Technology Inc "The High Reliability Software"
10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430
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