First of all, building kits, and possibly modifying some of them are good for monitoring HF frequencies is a good idea.
Second, of all, for VHF monitoring, using the modern radios (with spectrum display etc) for all day monitoring, even when I am not close to the radios, seems to me like a waste of energy, as many of them use more than 1A, just in RX mode.
Enter the old IC-202. I have two of them, one heavily modified (I need to determine what I did with them), one that I got later, and it seems to be in order. Those are good for some SSB/CW monitoring, where the exact frequency is not all to critical. The great advantage when using them for all day monitoring, when in the house, but not near the radios, is the much lower power consumption.
The IC202 is a 2m VXO controlled SSB/CW transceiver with max 3W out, and a stand-by RX current consumption of less than 100mA.
I have another old ICOM in the same family: The IC-402 for 70cm. About 100mA consumption on that one, too. Good for 70cm monitoring. When checking that one, I found that I had not removed the old Alkaline batteries, but the leak did not appear to have caused damage.
The 402 could also be used as base receiver (or even transceiver) for down converters or transverters for microwave.
The fourth transceiver found in the cupboard is the IC-502 for 6m. It covers 50-51MHz with a VFO, also with a current consumption of about 100mA. This one, I suspect will be a bit tricky to tune to the correct frequency, due to the larger coverage. For monitoring I may use one of the other transceivers to provide a "tuning aid".
I am trying to run more and more of my operation on solar power, so the power consumption will be critical, especially in the winter time when very little sunshine is available. Reducing the stand-by RX current to about 350mA for 6m, 2m, 70cm all-day monitoring is a big step forward, compared to several amps used by the "big" radios, just for general monitoring of 50/144/432MHz.
These radios will likely need to be checked and aligned, so here is another project for the late summer to winter activities.
Yes, the current solar power system still needs to be improved for winter use. Still, I expect to need to need topping up the battery storage in the months of December and January. That is okay, if I can use the station on (mainly) solar power most of the year.
Update: Did a check of the IC-502.
The VFO frequency is rather unstable and very sensitive to very small movements in the casing.
Volume control and RIT/fine tuning (all with potentiometers)got some contact cleaning (without residue after cleaning), and so did the on/off/light switch.
The volume control and the RIT work perfectly now, as does the on/off/light switch.
I suspect that the fine tuning pot could get a better cleaning, as it still shows some roughness. This may require some disassembly of the set.
For now I will leave the set on for a while with low supply voltage (8V in place of 13.8V), to see if the electrolytic capacitors are in working order
I also have to remove the power connector, as I do not have a corresponding plug for the 3-pole connector mounted.
A modification for feeding power is needed. Probably using a cable soldered directly into the transceiver
For now, after a longer power-on test, I think that this set can be used as a monitor receiver for, say, 50.100MHz, the general CW/SSB calling frequency.
Current consumption with moderate AF out was about 90mA, as I expected.
For 50MHz general propagation monitoring I expect to use the 50MHz part of my R6000 for now. With a modest amplifier indoors, and a satellite/TV power splitter, I should be able to use that antenna for this, with at least two receivers connected:
- The IC-502 for SSB/CW
- The old Tokyo HyPower handheld for FT8 monitoring.
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