Dear group,
here comes a log of stations received last weekend:
UT kHz call dBµV/m dist
Friday, 28.9.01:
2204 136.7 OK1FIG +13 376km? beginning of our QSO
2018 OK1FIG +23 end of QSO (nighttime QSB)
2027 136.5 EI0CF +11
2330 71.924 M0BMU ? 841km
2330 71.9215 G3AQC 0.1 Hz DFCW
Saturday, 29.9.01:
0925 136.9 OK1FIG +19 stable daytime level
136.66 DL3FDO +23 197km
136.9 PA0BWL +7 474km
136.9 DF0WD +14 357km
137.3 DJ5DI +4
1315 136.83 OM2TW +10 496km?
136.83 DF0WD +15
136.83 SM6PXJ +3 1035km
136.5 G3KEV +9 963km
136.8 DK6NI +28 20km
1435 136.8 OM5CW
2330 135.923 M0BMU +0...+6 QSB
Sunday, 30.9.01:
0857 136.59 DL5WF +4 135km?
136.69 G3KEV +6
136.76 OM2TW +7
136.61 OK1FIG +18
0903 136.54 DK6NI +28 20km
136.76 OM2CW +7
136.76 DL3FDO +22
0922 136.76 DJ7RD +26 129km
137.16 carrier 0 FSK bursts 1.8s, bear. 285°
136.68 carrier -1 FSK bursts 40s, bear. 285°
136.549 DCF IM -11 165km (reduced since 22.09.01)
135.36 DCF IM +28 165km
0938 136.6 SM6PXJ -2
0940 136.7 G3KEV +9
136.7 DK3GH +24 23km
136.56 M0BMU +2
1040 137.59 OM2TW +6 QRSS/DFCW QSO
1209 136.7 DK7SU +10
136.9 OZ8NJ +6 436km
1910 138.83 DBF39 +68 310km
The fieldstrength measurements were taken from calibrated spectrogram
readings and should be accurate to a couple of dB's. Given the distance d
from my QTH (JN59NK), you can estimate your radiated power by the formula
EMRP /dBW = FS /dBµV/m - 79.55 + 20 lg (d /km) + GL /dB.
The additional ground-wave loss GL is generally neglegible for distances up
to 100 km. Assuming no ionospheric propagation (which is not valid for
long-distance paths, especially in darkness), GL can be estimated from the
CCIR ground-wave charts, and for average soil conductivity (land, 3 mS/m) one
gets a table like this
d/km GL/dB
1 0
100 1
200 3
300 5
400 8
500 9
600 12
800 17
1000 22
1500 31
73 de Markus, DF6NM
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