[time-nuts] How I got my FE-5680A to lock in Sydney, Australia
csteinmetz at yandex.com
Sun Feb 9 23:37:29 EST 2014
>Here's what I found, as before looking at the frequency with my
>counter (GPSDXO 1pps timebase):
>Inverted position: swings between 9,999,798Hz and 10,000,001Hz,
>Normal position: swings between 9,999,756Hz and 10,000,057Hz, a few times.
Are you sure you didn't transpose the "high" swing numbers? As you
state it above, the oscillator swings 203 Hz (peak-to-peak) when
inverted and 301 Hz p-p right-side-up. If we swap the "high" swing
numbers, it is 245 Hz inverted and 259 Hz right-side-up, which seems
more plausible. There seems to be little reason why the absolute
value of the sweep range would vary so much (203 to 301). Also, a
normal range of 9,999,756 to 10,000,001 and an inverted range of
9,999,798 to 10,000,057 would seem to explain your previous results,
while the results reported above would not.
I'm a little confused by what you've said about your counter time
base -- as I recall, you said you were feeding GPS 1pps to the
counter. I'm not familiar with any counter that locks to 1pps --
most counters I'm familiar with lock to 10MHz (or in older gear, 5MHz
or 1MHz). Can you say a bit more about your "1pps timebase"?
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