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Cake day: June 11th, 2023

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  • The AM broadcast stations aren’t going anywhere, at least in the US. Above the broadcast band is mostly aircraft, marine and the 160 meter ham band. None of that is likely to change.

    Below the AM broadcast band are non directional beacons. Those are slowly being decommissioned. Eventually they will all be gone and that spectrum may get repurposed. I don’t know what the spectrum may get used for, but it would be nice if the 630 meter ham band was expanded.

    LF and MF can be used at low power. The 2200 meter ham band has a power limit of 1 watt EIRP and the 630 meter band has a limit of 1 or 5 watts EIRP depending on the country. Actually radiating that much power is difficult because it’s not practical to build an efficient antenna. Luckily there is no limit on how much power the amplifier can put out, so we can put hundreds of watts into a very inefficient antenna. Narrow band digital modes work great on those bands.

    In the US, we have LowFER, which allows hobbyists to use 160-190 kHz for experimental use without a license. The power limit is 1 watt input and the transmitting antenna is limited to 15 meters. People still manage to make long distance contacts with those significant limitations.




  • Keep in mind that without working repeaters, the baofeng will only have a range of a few miles on level ground with nothing in the way. If the power goes out, most of the repeaters will go down too. Some have battery backups that may last a few hours to a few days. Depending on where you are, a few may be solar powered, but heavy use will drain the batteries. Some repeaters are also reliant on the internet for linking to increase the coverage area.

    What you really want in that case is a portable HF radio and a wire antenna you can string up over a tree branch or a support with a fishing pole. In the daytime, you can use the upper HF bands for long distance communication. That has a range of thousands of miles, but nearby stations won’t be able to hear you if they are beyond line of sight. Since the portable radio doesn’t have much power, you may need to use digital modes to get through. For more local contacts you can use NVIS propagation on the lower HF bands. That has a range of several hundred miles and can even be used to talk to someone on the other side of a mountain. Even 5 watts and an antenna strung 3 feet off the ground can work for voice contacts out to over a hundred miles.