[time-nuts] New Time nut FRK-H repair questions --- IT Works!!

Hal Murray hmurray at megapathdsl.net
Fri Nov 23 02:42:25 EST 2007

> I only have an old HP5340A with OCXO option as my frequency meter.

How good do you think the calibration on the OCXO is?

> I have a GPS  receiver I have to get going that has a 1PPS output on
> it.  What would  be an appropriate way to use this to calibrate the
> FRK - in my lifetime:)

The PPS will have some jitter.  The ballpark is the crystal frequency on the 
GPS unit.  I'd guess 50 ns.

Use the FRK output as an external clock on the 5340.

Use the 5340 to measure the time between a pair of PPS pulses.  Average over 
several/many measurements.

Trigger a scope with the PPS.  Look at the sine wave from the FRK.  If it 
moves, the frequency is off.  If it takes a 100 seconds to move a cycle, it's 
off by 0.01 HZ.

These are my opinions, not necessarily my employer's.  I hate spam.

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