A local amateur, OZ5AR has started taking the challenge of low power seriously. I should do the same.
He started building a simple circuit, yes, it is just an attenuator. The output (and therefore the attenuation has not yet been measured, and he did not tell me the value of the series resistor part, so I do not yet know how low his power was. Calibration needed.
The signal went from about S5 down to an easily readable CW signal with practically no S-meter output.
We have both tested the lowest power output of our standard rigs, the IC-7300 and the IC-7600, and measured it to be between 700 and 1500mW. A more precise measurement is needed.
The distance between us is almost exactly 2km. My challenge is to see the minimum power necessary to make a contact, and preferably go below 1mW. A contact like this would actually qualify for an award: The 1000 miles per Watt Award. Just for the fun of it.
The initial test is on 28.322MHz, a frequency to which a "standard" crystal oscillator is available. The frequency (+/- the tolerance of the oscillators) is also used by Italian stations for very low power QRSS transmissions.I do have attenuators available to reduce the power from 1.25W to approximately 1mW. More when I have had the time to find everything. The next few days are quite busy with going on and receiving visits.
Yes, we will test as many bands as we can, but the experiments will have to finish some time next year. For some bands, like 472kHz a transmitter needs to be built.
I would like to do the experiments with home brew transmitters (and, over time, receivers), just for the fun of it
Yes, yes, never running out of ideas ...
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