I was transmitting wspr on 40 at 100 mW from a WSPRLite tx, and monitoring
on an antennaless K3 in SSB mode (just listening in SP3, not trying to
decode). (Background: I have for a while been fascinated with how room
accoustics will sometimes, with a given head position, make the tone in cw
reception almost disappear). Watching the WSPR signal on the P3 at minimum
span, I could see two sideband peaks well separated from the carrier. Tuning
slowly I noticed something similar to the cw/room accoustics phenomenon: At
a certain tuning point the whistle from the speaker got very quiet. Moving
my head around I concluded that this was probably not room accoustics but
some kind of characteristic of the wspr modulation. Be that as it may, then
came a big surprise, and here is my main issue for the group: Suddenly there
was a loud click followed by complete silence, which lasted a second or so.
It was like someone had ripped the speaker cable out of the radio. The
normal sound then came back, but several seconds later the click and silence
came again. This seemed to cycle forever. The picture on the P3 remained
steady, so the wspr tx did not interrupt its operation, and the K3 front end
kept operating normally. I then tuned around, changed the rx to cw, etc, and
the phenomenon went away. Normally I would take time to study further before
bothering the group, since many things could cause a break in rx audio, but
I have not been able to repeat it. One thought that came to mind was that
somehow the K3 dsp got saturated and hickuped, but the received signal was
quite weak on a quiet band, only about 20 or 30 dB above noise, and hardware
agc should prevent that anyway. While I am waiting for something similar to
happen in the future, I am just asking the group if anyone has had a similar
experience.
Thanks in advance,
73,
Erik K7TV
______________________________________________________________
Elecraft mailing list
Home:
http://mailman.qth.net/mailman/listinfo/elecraftHelp:
http://mailman.qth.net/mmfaq.htmPost: mailto:
[hidden email]
This list hosted by:
http://www.qsl.netPlease help support this email list:
http://www.qsl.net/donate.htmlMessage delivered to
[hidden email]
Locked
