[PPRAANet] Yaesu microphone locking

[Douglas Hagerman]

After bouncing around in a car all day yesterday in constant fear of accidentally keying my microphone, I decided to poke around on the Internet to see if there was a modification that would allow me to lock it completely. This is on a Yaesu FT-7800, which comes with an MH-48 handheld microphone. The mic has DMTF buttons plus a few others that have various functions, plus the big PTT switch that is so easy to sit on. Also it has a switch that turns on the key illumination, and a lock switch that only locks the keys--but not the PTT switch.

I found this schematic, http://homepage.ntlworld.com/rg4wpw/mh48a6j.pdf which seems to show that there are jumpers inside the mic that change the function of the lock switch. The table on the lower right shows various jumper configurations, including one that apparently locks all of the mic functions, including the PTT switch.

Has anybody played with this feature? Just curious about what sort of trouble I'm about to get into…  :-)

Thanks.

W0UHU Doug.