At 01:13 PM 9/12/2005 +0100, Andy wrote:
Seem to recall talk about a few datamode software authors who
were contemplating adding some GPS capability to their products and I was
wondering if anyone has information or progress on this. G4JNT
AFRICAM has GPS-sync capability - it has proven most useful with very
slow BPSK where it would otherwise take a long time to find the signal.
Did some tests last season with it - the error correction capabilities
aren't as robust as those in WOLF. It's easy to do the GPS part, just
put the 1-pps onto the Ring Indicator pin of a serial port. If the rest
of the serial port is available (i.e. you use a sound card instead of the
usual sigma-delta serial interface board) - then you can use the serial
port to monitor NMEA output from the GPS unit - AFRICAM only uses the
$GPRMC sentence to set the computer's clock so he knows for sure which
second each 1-pps input pulse corresponds to. If the serial port is not
available you must manually set the computer's clock to within a half
second or so of UTC immediately before starting AFRICAM - thereafter it
keeps track of time by counting the 1-pps inputs.
AFRICAM can be used with a sound card - but not very user friendly -
it works great with my sound card, others have found it hard to set up :)
This is a DOS program, doesn't get along with Windows. If you're
interested, you can download it from my website:
www.magma.ca/~ve2iq
Documentation is weak - any questions, I'll try to answer by e-mail - it has
been a while since I last looked at it.
Bill
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