Here is my build of your idea. The MMBT3906 is on the K1 power lead. The Base 12K goes to PTT and Collector 11K goes to ground and will be connected to the 2N7002 SMD I propose to use. The resistor values are chosen because I don't use many from my sample book!
I tried Allisons mute idea of a 56K resistor from emitter of 3906 to input pin of 386 and that reduces the POP significantly!
See files section RTAUD1.jpg in Allisons folder.
There are 1A diodes across the power, TX and RX lines. The ceramics are additional click filtering for the relay.
Raj, VU2ZAP
Raj vu2zap