This afternoon I had my first QSO with the Flex 1500 and PowerSDR 2.0.16 using
an external keyer. I'm an absolute beginner with any flexradio product - I
bought the rig long ago, received it when they began shipping, and put it on
the shelf (as I'm exclusively CW op) until 2.0.16 beta was released. So, today
is my first on-air experience with the rig. I was able to upgrade from 2.0.5
(out-of-the-box CDROM) to 2.0.16 beta without any difficulty.
Where I'm struggling: I notice a pronounced "hesitation" effect with the first
transmit symbol, and also hear a slightly off-frequency carrier (on another
receiver in the shack) during transmit - a kind of "backwave" but not on the
exact TX frequency. I don't think either of these is news to the developers or
reflector, but I just wanted to see if I should be making any
configuration/operational changes before putting rig back on shelf awaiting
later software version. I did try adjusting CW TX buffer size between 256 and
2048 and didn't see much difference. I did find it necessary to run keyer's own
sidetone (with "Disable Monitor" selected on powersdr) as powersdr sidetone is
delayed enough vs actual sending, and powersdr sidetone audio level is
dependent on transmit drive level (which means no powersdr sidetone when tx
power turned down to 0 for testing.)
To work around the first-symbol hesitation, I was able to complete a QSO by
setting the "break in delay" parameter to ~750 mSec (so basically I could send
a whole transmission without the rig dropping back into receive.) I tried a
simple test of sending a string of dits at modest speed, and adjusted the Delay
parameter down to 0 mS (QSK hoped for) and discovered the shack receiver was
not hearing any useful signal (certainly not a string of dits). Until the delay
was set long enough to keep the rig in transmit between dits, I could not
obtain a workable transmit signal.
The machine is an ATOM 1.6 GHz box with XP and is doing nothing but running
powersdr. CPU utilization seems to be 50-60%.
I looked at the flexedge archives and 2.0.16 release notes and didn't see any
advice that seems directed at the first-symbol hesitation which is my main
concern.
Thanks for any advice,
73 Dave WB0GAZ
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