This page includes some tips that might help you out with your VX-5 or you might find the information helpfull in another way. Also there are some links to some other VX-5 sites.
The VX5 has a bit of an odd connector for the speaker mic external connection. This means that the appropriate 3.5mm 4 ring connectors have to be sourced from somewhere.
I have done some experimenting in this are and havbe come up with the following ideas:
With a standard 3.5mm phones jack, it is possible to serve all the functions
that the 4 ring plug will. It is a little bit tricky and there are a couple of
things to watch out for, but it is possible to do it.
For TX and RX audio, the plug is inserted into the jack so that it is about 2
or 3mm proud of where it would normally seat in the jack. This makes connection
with the speaker, microphone and ground connections.
The main problem with doing things this way, is that you run the risk of
shorting out the transmit and ground lines and therefore transmitting
constantly.
The other thing to note is that if the plug is not in the right position, then
the radio will not transmit from the external plug.
Programming cable for the VX-5. (This is a programming cable for the VX-1,
but they are the same. I have built one and had it working.)
http://www.icongrp.com/~sllewd/pcware.htm
You can order a VX-5 pocket reference book from this site.
The software refered to on this page can be downloaded from http://www.geol.com/vx5/
Leighton Judd - VK3HLJ