PTT Doesn't work without hardware encoder

[kxkayser]

It seems that just connecting a PTT switch as described in the documentation (either the simple setup or the "safety" setup) does not function unless a hardware encoder is also attached. Even though the Encoder is enabled in dvpimanager as described in the documentation, This has been verified by at least 4 users. My goal is just to have the externall PTT to work without any additional hardware. Thanks for the great project.