Are some Ham gear manufacturers (large and small) known for providing detailed documentation like block diagrams (at least) or schematics? Or maybe the case for which detailed documentation like service manuals can be easily found?
While I don't expect to make many mods, I have found this information very useful on my iCOM 7300, like to see exactly where the preamplifiers are located, how the analog filtering works, grounding, etc. For a very old Swan power meter I bought, the schematic showed me exactly how it works (e.g. how it measures PEP), and will allow me to make a mod I am considering.
I am a new ham, and here is my experience so far:
For my Icom 7300, I easily found a service manual with a block diagram and schematics (not sure if this is officially provided documentation but it is out there).
For my Samlex power supply, I haven't found any block diagram or schematic, although I haven't searched that much.
I was looking at the Yaesu FT-65R and couldn't find a block diagram or schematic, after looking for a short time.
I bought a nanoVNA v2 and officially it is a "closed" design (as opposed to the earlier nanoVNAs that were open) and I think there is a block diagram, but I have yet to find a schematic.
I bought a very old Swan Power/SWR meter, and the user manual included schematics. The schematics didn't exactly match my model, but were close enough to be usable.