Walter,
Interesting! Is that RADIATED power or DC input?
It is output power. The beacon TX feeds 1mW into the coax.
The output voltage from the signal generator is 1Vp-p and there
is a -4dB attenuator between the generator and the antenna
feedline. The antenna is a dipole at about 8m height with approx.
20m RG58 feedline. The antenna appears to be well matched at
this frequency, close to 50+j0 ohms at the TX end of the coax.
The actual radiated power is less than 1mW due to the well known
"garden loss" (although I doubt that this beacon will heat the soil
enough to make the carrots grow faster and bigger :-)
My 0.5 mW (radiated) on 136 kHz has only made 300 kms so far.
(1W RF into antenna coil)
The atmospheric noise level is MUCH worse on 136kHz.
73
Johan SM6LKM
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