I understand your concerns. I had hoped there might be some easy answer to add these presets to multiple Yaesu radios at one happy swoop.

I’ll probably return to the special memories model. The preset index in the radio’s memory is indeed separate from the other memory locations as are the presets themselves because they’re not contained in the _mmap. E.g., memory 0 is index 0, skip 0 is 900, scan 0 is 1000, all in _mmap, while weather 0 is 0x1000, marine 0 is 0x2000 and actually stored who-knows-where. The only marginal hassle is that it becomes a very long list if it’s filled or if one shows empties.

I do suggest that you keep the “steps” I outlined around as a starter tutorial for those who need to use sub_devices. And warn others that VARIANT may have side effects, or perhaps duplicate functionality to two variables: VARIANT and SUB_DEVICE to avoid the over-overloading.

To that end, I’m attaching my template.py that just barely works, but starts to implement the sub-device tutorial idea. Use or not, q.v.