Adding Load to Solar Power.

For the winter the old load on my shack solar power system has been just the IC705.

The nice thing about the IC705 is the band coverage. All bands between 160m and 70cm, with the exception of 4m. Then there is the spectrum scope. That is a great feature. Third, the power consumption is only 300mA at receive. I am considering getting one more, but as the more advanced HF stations draw much more power, just receiving:

FT817: 400mA

IC703: 600mA

IC7300: more than 1A

IC7600: even more power than the 7300.

IC7100: I think it is below 1A, maybe about 800mA

In winter time with the current solar power system those on the list above cannot be run on solar power.

Today I made the beginning of a small  low power system:

Using a pair of computer speakers I connected the speakers to my 4-band CW QRP transceiver, the HB-1B, drawing only about 80mA capable of running 20, 30, 40 and 80m. The HB-1B only has a headphone output jack, so more audio power is needed for speaker volume. The HB1B does have a variable bandwidth crystal filer, and can be used for both SSB and narrow bandwidth CW reception without additional filtering. The system works nicely. Later the computer speakers may be replaced by a separate audio amplifier box (with additional circuitry) built into a single box. 

I intend to expand the system with more transceivers, and later some switchable filtering:

Split the inputs, so that one SSB/CW receiver goes in one audio channel and one more in the other. A third one can be added with the output evenly split between both inputs, creating a "centre channel".  One of those receivers could be the old PM2B set up for 20,40 or 80m reception. A repair/modification will be necessary for the 80m preselector, but that should not be too tricky. The PM2B is also very convenient to add to the monitor system, as the power consumption is only 20mA, easily added to the current solar power system.

This means that 3 different signals can be distinguished. Since these signals have a noise floor, the idea is to add 3 FM receivers in parallel, making the signals from 6 receivers distinguishable/audible via the 2 channel audio system. This requires a simple mixer system that I can construct without too much difficulty, making the monitoring of 6 different frequencies possible, as the FM receivers will be squelched, and therefore distinct from the SSB/CW audio.

Later some audio filters, and maybe equalizers and input switches can be added to this system.