[time-nuts] HP-117A and MSF ?

[Iain Young]

Hi All,

Has anyone considered using (or even used) a HP 117A for receiving and/
or measuring MSF ? I had one of those mad idea evenings last night after
comparing MSF to the Greenwich Time Signal for a few days (More info on
my next post...)

But back to the mad idea, I thought I might use a 117A to:

    o compare MSF against my three LORAN boxes (Yes the 1Meg would need 
to be divided down...)
    o Use the Signal Level 1/4" stereo phone jack and a resistor to feed
a time decoder, for yet another clock, just to help justify having the
117 [and to compare my SDR decoders to of course...] :)

The potential issues I thought of (so far) are:

    o 50Hz vs 60Hz power. Not really a big issue, I can get converters
to solve this one.

    o Being a TRF receiver, and with me only having an LF whip with
pre-amp, I'd need to add filtering, but again not the end of the world.

    o 30V on the antenna line. Seems that I may be able to use the test
connector. Alternatively, a Bias Tee, or just cutting the DC supply to
the antenna connector should suffice, I can't believe it would be that
hard

   o MSF off time. Now this might be a bit more of a problem for phase
measurements, MSF doesn't just reduce the carrier like WWVB and DCF, but
drops it entirely.

     Anyone know if this would "just" give me interruptions to the
comparisons, during the 100-300 msec off times, or would it entirely
mess up the comparison with the "house standard" ?

     I'm guessing it would depend on if MSF just cuts the carrier from
the output stages or if they stop the actual carrier generation...

Any other issues I might run into other than the usual aging issues and
so forth ?


Iain