Join Date: Nov 2010
Location: Gilbert, AZ, USA
Re: Poor man's way to plug a phone into intercom
It's pretty straightforward. Two 4-conductor (three-stripe) plugs and audio cable between them. The rear-most conductor goes to the second-rear conductor, and vice versa. The pin-outs are commonly available online. From the front, the conductors are:
Mic on Autocom end, ground on phone end
Ground on Autocom end, mic on phone end
I used a pair of cables from Radio Shack that had nice connectors already heat-sealed on the end and used very thin audio cable with a nice fabric sheath on it. Each cable was $7. Splice red to red, blue to blue, yellow to green, green to yellow.