[Ham-Mac] Simplex repeater controller?

[Louis C Bruckner]

Hi, Everyone
I have had an interest in putting up a GRMS simplex repeater since I 
bought 2 motorola maxar 80's that are very close to the GRMS band and 
use a digital CTSS tone. Alas I can't find a good duplexer for any less 
than $400.00 witch is way out of my spending allowance that the XYL has 
deemed suitable. ;-)

So I was thinking it would be a simple to use an old 7500 to do the job.
Since I have over 10 of them in the shed that I bought from the state 
for less than $50.00
I have used them for webcams since they have built in video capture.
I donated one 7600 to stormstudy for their tower cam but the owner of 
the tower moved and we lost the tower space. ;-(

I have put up my own tower but I only have the first two sections up 
and I need someone that is lighter than I to put up the rest. As soon 
as that happens I am donating tower space for the cam and a weather 
station.
I already have my 2/70cm maxrad on it and two 2.4ghz wi-fi  antennas up 
on it.

Anyway to the point at hand does anyone have any ideas on how to 
interface the radio to a 7500.

I was thinking of using apple script for the app. and a old ADB key 
board as an hardware interface.
The digital CTSS board is separate from the main board in the radio and 
I am willing to bet I can find a connection to tap off of to sense when 
the DCTSS is receiving the correct tone and start recording the audio.
as far as using the ADB keyboard as an interface.
I could use the caps lock LED to power a relay for TX and use a relay 
to simulate a key depression to send information back to the 7500 for 
carrier sense.

What do yall think?
73's De KG4MXV