by Gadgetgeek » Sun 01 Sep, 2019 9:22 am
UHF is still very line-of-sight, but from a practical standpoint, 5 watts is enough that "range" is not really as much of a concern as terrain is. As in, loosing that line of sight will get you before the range does in typical walking situations. If I was walking with a larger group then having a radio at the lead and rear would be a good option just to keep the group together, and allow people to have a bit more space. Especially if you are sharing gear among the group.
As far as alerting authorities, its not something I would put a lot of weight on, however if you were going to take the radios, I'd leave the planned channels on your leave-behind info so that in the case of a search, the authorities could be broadcasting on that channel. UHF is also a bit easier to train people on if you had a larger group, and there is a higher likelyhood of someone being nearer the radio than the person with the PLB. Having a note with the radio to transmit every 30 minutes or every 15 minutes for a pre-arranged pattern (20 seconds transmit, 20 seconds listen 3x) helps people from sitting on the transmit button and killing the battery.
Lower wattage UHFs like the little 0.5-1watt units are not super effective for serious walkers, but if I was planning a walk with a bunch of people who had kids, I might consider those size of radios for the little ones to keep on them which would allow them to walk a little farther from their parents, with the higher wattage radios still being front and back.
Certainly a useful tool if people are able to use them. Very often though my experience with them in casual situations is someone gets a bunch of chatter on their channel that they don't want to listen to (aussies have atrocious radio discipline in general) and so they turn the radio down or off, and then forget to turn it back on.
Having had to carry a UHF for work quite a lot, it needs to justify its weight. So unless you are making a plan for in-group communications (again, large group, or a high likelyhood of having to do a hasty search for a child or something) It really doesn't justify its weight in my mind. A Spot or a Garmin Inreach does a better job of remote comms at a better weight, but there is that cost factor. So there is a chance that carrying the handheld is a better option because its what you have, and its better than nothing. As with all things, there is a compromise, and YMMV.