Dave,
There are two issues here - first, the signal being on a non-integer
frequency, and second, the signal having a non-GPS locked carrier phase.
The first can be handled by setting a non-integer offset to the software
(Peter calls this a 'spin frequency', because without it the vector traces a
circle at this frequency). This is quite effective when tracking such things
as LORAN lines. In other words signals that are GPS related but not integer
Hz frequency.
The second (non-GPS locked) problem means that even if the signal is very
stable, the phase you receive isn't meaningful, and you're not likely to
receive the same phase at the same time each day. If the signal is less
stable, you may not be able to retain meaningful integration for more than a
few seconds.
Since I know you'll be able to copy the same signals as me, I suggest you
try looking at JJY (40kHz) and the Californian FSK station 135925 or
135975Hz, as both are GPS coherent. There's also a weak one from Antarctica
on 20KHz and some European ones appear briefly at around sunrise on 75kHz
and 77.5kHz if you use a long enough intgration time.
Finally, I can send you a GPS coherent signal on 181.400kHz any time you
wish. I can also transmit any nearby frequency with or without 0.5Hz or
0.3333Hz offset!
Any stations in VK willing to try looking for my signal using Clicklock or
PhaseScope?
73,
Murray ZL1BPU
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