[time-nuts] FE-5680A PPS on pin 6 (or not)

[Tom Miller]

Hello Group,

I have been lurking for a while to get a feel for the group and hope to give 
back
something in return for all the good information found so far.

I have two of the FE-5680A units from the usual source. They both worked and
were much  less than 1 Hz off compared to a Trak Microwave GPSDRb house
clock. Can't say this is not one of the treasures found in modern surplus 
sources.

I made one observation about the 1 PPS signal. It is not present until the 
unit
achieves lock. The 10 MHz signal is there at power up.

I would be interested in using a vanilla GPS receiver that has the 1 PPS 
signal
to sync up the Rb clock so I am following those threads.


Thanks much,
Tom





------------------------------

Message: 2
Date: Thu, 12 Jan 2012 03:23:00 +0100
From: EB4APL <eb4apl at cembreros.jazztel.es>
To: time-nuts at febo.com
Subject: Re: [time-nuts] FE-5680A PPS on pin 6 (or not)
Message-ID: <4F0E4404.8070108 at cembreros.jazztel.es>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Hi,

I'm interested in seen those photos, because I collected a bunch of then
from various owners but I dont see this 'AC161 even on in the switching
regulator pair.
I made a goof the other day when I connected the 5 V input to a 15 V
power supply and toasted the 'ACT240 buffer which drives the lock
indicator and the PPS outputs.  I know that the 5 V is used to generate
the +3.3 V in an internal regulator and because I'm not sure what else
is toasted I want to trace this voltage and see if it is ok.  The unit
is mostly working, it locks and also generates the 1PPS, measured at the
input pin of the buffer, but I want to check everything that can be
damaged and replace the failed parts.
So I'll benefit from partial schematics, parts location and
identifications and all the like. Please share the info that you have.

Best regards,
Ignacio, EB4APL