Hello group,
quite an exciting weekend on LF.
Friday :
Rather poor condx, but fortunately also QRM level was low. VE1ZZ was copied
'M' here at several moments during the evening (between 20 and 23 UT, went
to bed afterward - a lot to do on saturday).
Of course many strong signals between 135.9 and 136.0, I did a kind of SNR
measurements using SpexLab at 0.3Hz bandwidth (comparing signals to
background noise). The 'top 5' was (arround 22 UT) :
OK1FIG = 58dB
MM0ALM = 45dB
M0BMU = 42dB
G3AQC = 40dB
G3YXM = 38dB
BTW : I had to insert 50dB attenuation to avoid that Petr triggered the AGC.
Further I took notice of some rather strong 'lines' close to 136.5 (SNR at
0.04Hz BW between brackets) :
492.2 (12db), 496.0 (4dB), 498.8 (22dB), 501.7 (7dB), 502.5 (18dB), 503.3
(15dB), 504.6 (10dB)
There seems to be much more of this rubish down the band, compared to the
137.7kHz segment. It would be interesting to know which of these lines are
local QRM and which are 'DX'.
Another reason to move up to 137.7 : some stations were very active just
above 136.5 in normal CW on friday night. Fortunately only 1 of them was
strong enough to affect VE1ZZ's signal and his activity was limited. At
least 2 of this stations read the reflector (and thus were informed about
the VE1ZZ activity), so could this be interpreted as a 'warning' against
QRS activity down in the band ?
Saturday :
Turned on the RX at 19.50 UT, the s-meter was dancing at S9, due to static.
As could be expected no sign of VE1ZZ. Static kept far too bad to copy any
weak signal at 0.3Hz bandwidth, so I decided to have a look at VE1ZZ at
0.04Hz bandwidth. Of course this is far too narrow to copy the dashes and
dots but on some occasions I could see a trace appearing on the expected
frequency at the beginning of the transmitting period and disapearing 10
minutes later. One time I could even see that it got fussy after 10 minutes
(when they started normal CW ?). I also could notice a very small
'wobbeling' on the signal, going up and down about 0.1Hz over the 10 minute
period.
73, Rik ON7YD
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