This is a good idea. But just a note for those that might not know, if you don't hear anything, it doesn't necessarily mean there is something wrong with your equipment. The bands "open" and "close" even now as we enter the solar max. Sometimes you just have to be patient till they open again.
@WSDD439 Don't get me wrong, I'm not arguing with you, I'm just explaining the issue that some people have with linked repeaters. Personally, I don't care whether they are linked or not. They are useful linked, they are useful unlinked, and simplex is also good.
My UT-72 came with one but I didn't use it because I have a mobile. The adapter is a thin cable. Not long enough to worry about loss but being flexible eases some of the strain on the SMA of the radio.
Everyone has an SHTF and they all stink.
Seriously though, for a few days after Beryl, neither land line nor cell phones worked for my family. I was still able to communicate via GMRS and ham. I've been thinking along the lines of emergency comms for about a year now and I think it's a good idea to have at least some kind of plan.
Not sure I understand exactly what you mean here so forgive me if I misunderstood. You can use slit tones on simplex. Not sure what the benefit is other than possibly making it harder for someone to interrupt both parties at the same time.
When people talking about two-way radios and use the term "net" they are usually talking about a meeting of sorts on the radio. Connected repeaters are usually referred to as "linked" repeaters which are becoming a thing of the past for GMRS in some areas.
You have as much access to the owner as any of us.
Depending on your radio, you may be able to scan for the tone. Check your manual to see if it has this feature.
This may have been just a typo but it is an offset not a step. A step is the amount of frequency change with each press of a button or click(detent) on a dial.
Sometimes I think they forget to update the version number after making changes and before burning it into the next batch of radios. I have two UV-5Rs that are supposedly the same with the same firmware version. I can change the startup message on one but not the other.
I like @BoxCar's solution and would like to add that if you go with an HT like @WSDT603 said, you may want to use a BNC adaptor for the antenna. I've heard that SMA isn't designed for repeatedly adding and removing the antenna and therefore more prone to failure after repeated use than BNC which is designed for repeated use.