[Elecraft] re UP & Down features on mic

[Fern Rivard]

   Can anyone please enlighten me on whether the UP and Down feature on the microphone connect work against ground or +8 volts dc. Although I purchases the optional electret style of hand microphone, I much prefer a good dynamic microphone. I'm presently using the Shure 444D dynamic desk microphone with excellent transmit audio report. I've just tried a dynamic hand mic meant for the TAD line of commercial radios with also excellent transmit audio. This hand mic also has the UP and Down buttons so I would like to wire that feature but need to know as to whether it works against ground or + 8 vdc. I will be selling the factory electret hand mic for anyone interested.
    Fern