I wish it had was meter for the transmitter battery and not just an alert when it's low,
I think the transmitter just sends a status report, like OK, weak, and critical/almost-too-late. This takes fewer bits (2 is sufficient) than actually sending a voltage....Yeah, I thought about that as well. But, I’m thinking this might be a limitation of the transmitter. My Oceanic VT4.1 did have a menu option to check the transmitter battery, but if it was good, it merely indicated “OK”. Didn’t give a percent or voltage. Likewise, my downloaded logs in Subsurface also show that the transmitter voltage is “OK.”