Hi Al,
In programming my new Baofeng F8HP, I was surprised that 15 kHz wasn't a valid step value, since that is the standard US channel spacing on 2m.
STEP is only used in VFO mode. It is like a mask when entering a frequency into the VFO to help reduce entry errors. It is also the change in frequency when scanning the VFO. You can get by just using a STEP of 5.0 KHz for this purpose. STEP is unused and unneeded when programming memories into the radio with CHIRP.
In looking through the drivers, the STEP values seem to be very radio specific for reasons I don't yet understand. Before I put in a bug and patch to add 15kHz to the uv3r driver, I need to ask whether there a specific reason it isn't already in the list which makes it incorrect to add it?
It would be incorrect to add it. As you already noted above, it isn't supported by the radio. CHIRP is unable to force a radio to do something is isn't capable of doing.
Thanks, Al WA1TYB
Jim KC9HI