I just got a Yaesu FT-60R handheld, along with the MH-37A4B earpiece. After having it around for a couple days, I think I'd like to be able to connect standard headphones to it, so as to be able to listen privately without carrying around an extra accessory.
I see that the pinout for the 4-contact combined "MIC/SP" jack is known, though not in the manual, and there is a a first-party adapter cable (CT-44). However, this doesn't tell me without buying/building whether it's possible to use it in the way I want; specifically:
If I connect only headphones to the FT-60, using an appropriately wired adapter, can I still use the internal microphone and PTT switch to transmit, or will just having a plug inserted cut out the internal mic?
(I haven't tested this out because I don't have a bare 4-contact plug to experiment, and I hear that plugging in headphones with a standard 3-contact plug results in misbehavior.)