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To All from PA0SE
At 1737 UTC I heard and worked G3WSC/P with
Derek, G3GRO at the key.
Their signal was -70 dBm (S9 + 3dB) at the receiver
input. The corresponding field strength is 32 microvolt/meter. ERP was given as
1W and transmitter output as 10W.
At 2000 UTC I listened on 73 kHz but heard (or saw on
Spectogram) no signal. But local noise level is pretty high in the evening
hours.
I had just completed an untuned single turn screened
loop with an area of 1 metre squared.
Connected to a Wandel & Goltermann selective level
meter type SPM-12 (a recent acquisition) I measured the field strength of DCF139
(138.83kHz) in the shack at 2 mV/m and of DCF77 (77.5
kHz) at 3.2 mV/m. These values were used to find the relation between field
strength and receiver input voltage.
When one of the coming days it is dry I will
repeat the FS measurements in an open field. This can be easily done because the
SPM-12 can also be fed from a 12 V battery. The results will enable me to use the station receiver as a field
strength meter at both 73 and 136 kHz.
I am looking forward to more of these interesting
"Decca" tests!
73, Dick, PA0SE
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