I am currently trying to write software to control the Pegasus. I'm
discovering that one of my design criteria is probably impossible, but I'd
like to get as close as I can. That goal would be to have a scan display
similar to the Icom 756 which I owned a few years back. With that display, I
was able to not only tell the presence of adjacent signals, but also in a
lot of cases, the type of signal.
I realize that the hardware of the Pegasus doesn't allow for simultaneous
display of the frequency scan and listening to the current signal as there
is only one receiver..
However, I have also discovered that the max scanning rate seems to be
limited by the recovery time of the AGC. If you scan too fast, the display
takes on a sawtooth appearance. The only way I have been able to reduce this
is to delay 50 msec or so between readings. Any shorter than that and I get
the sawtooth. But 50 msec means I can only scan 20 points a second, so you
have to trade spectral resolution for temporal resolution. In either case,
you don't get a 756-like spectrum.
I was looking at the ad for the Jupiter in the February QST and see the
spectrum display. It doesn't show have any sawtooth appearance, and I would
like to know from those who have a Jupiter how fast it scans.
I would also appreciate comments as to the appearance and or usefulness of
the frequency scan on the Jupiter screen vs. the scan on the computer when
using control software.
If the Jupiter internal scanning turns out to be better than the Pegasus,
perhaps we can encourage TT to put some scanning code into the Pegasus
firmware.
I'd appreciate any tips anyone has on frequency scanning with the Pegasus.
73,
Mark, N8ME
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