W8JI MEASUREd:
> At 9AM today the beacon (500 miles or more distant) on 1791kHz
> measures -96dBm (75 ohm system) on a southwest 500 foot long
> Beverage. Noise is -128dBm on the same antenna using a 3 kHz
> filter. ~32dB S/N ratio @ 3 kHz BW.
>
> That same signal is -94dBm on my 200 ft omni-tower, and noise is -
> 107 dBm (three kHz BW). ~13 dB S/N at 3 kHz BW.
Why do you need -145 dBm sensitivity even on dead 160m band at 9 AM?
MEASURE the signal levels overnight.
73 de Mario, S56A, N1YU
P.S. I was talking of 40 dB pads!
To I4JMY: FT-847 FET mixer works on 3 V and few miliamps DC. What kind of input
RF signal ENERGY it can convert?
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