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THE VOX BOARDS
Here are two different vox circuits,
the first is built with a 2N222A switch for low current
applications, note that the board plugs directly into
the mike socket and draws 4mA  from the 5 or 8 volt pin.
Traces on the board route all mike functions such as
up / down , ptt, vcc, ground etc. between mike and radio:
opampvox1

Here is the top of the board:opampvox2

Here is the bottom: note jumper
opampvox3

Schematic : Modified from  N1HFX http://www.rason.org/Projects/basicvox/basicvox.htm
opampschematic

Parts placement:
opampparts

The copper traces:  80 mm  X  50 mm
opamp trace

SECOND VOX BOARD:
This board  uses an outboard 9 volt battery and a relay
for higher current applications. It sports a nice sensitivity/gain control and a delay or " hang time " adjustment. Also has  an LED to confirm PTT activation. Works very well:

voxpix4

voxpix3

Parts placement  with traces showing through:
vox4

here is the schematic:vox5

The  copper board:
vox6