Hi Bill,
I think the other traces disappear because the AGC is enabled?
BTW your trace at 136.170 kHz may reduce the S/N of the wanted signal
since it affects the noiseblanker treshold. So better switch it OFF or
reduce it to 10 dB S/N or so.
Just started to TX in QRSS-60, transmitting until arround 6 UTC here...
73 es good luck.
Stefan/DK7FC
Am 07.09.2011 23:24, schrieb Bill de Carle:
I noticed my marker line was getting chopped up at times on both
Spectrum Lab screens. At first I thought it was another strong
carrier off-screen for the SL display but still within the 500-Hz Cw
filter's passband. There are several clearly *audible* signals in
there at times. So I brought up ARGO for a wider view using 3-second
dot mode. You can see my marker at 136.170 Khz along with several
other much stronger signals. Around the middle of the time grab it
seems as if everything went dead - in fact it was a 45-second burst of
local noise. Not much of anything audible but I saw the S-meter jump
up about 30 dB (cutting back the RF gain and making the other weaker
signals disappear). Interesting how the background looks exactly the
same during the noise burst as at other times. We don't *see* any
noise here, we see the *absence* of all the usual signals. That noise
is what chops up my marker lines on the two .usr spectrum lab
screens. Although still full daylight here it's getting near supper
time and people are turning on appliances. Things will quiet down
later hopefully. Here's the ARGO screen:
http://www.nrtco.net/~ve2iq/grabs/136argo.jpg
Bill, VE2IQ
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