First off, draw a hookup plan of your radio to the modular jack box.
The modular jack box will have two sets of wires connected to each screwinside the housing.
Looking at the JACK with the notch DOWN, the pinout will be numbers 1-8from left to right.
|Pin 1.||+8 volts|
|Pin 2.||Frequency up/down|
|Pin 3.||AF out|
|Pin 5.||Mic Ground|
|Pin 6.||Mic Input|
|Pin 8.||Squelch switch|
Cut the modular cord to the length you need, and verify with an ohmmeterthat you have pins 4 and 7 correctly identified. Wire these to the footswitch and you're finished with this part.
I used the cord and plug from an Icom hand microphone I had on hand, but you canroll your own if you so desire. This is where you must be careful and pay close attention, hence my suggestion for a drawing of the hookup before you start. Match the function of each wire to the other as the numbers are different, i.e. +8 volts to +8 volts, mic input to mic input, etc. I used small terminal connectors, soldered the wire to them and then fastened them to the terminal strip inside the modular box. Connect to the rig and plug in the footswitch and headset. Then contact a person who knows how you sound, and adjust the audio controls of your rig to make everything sound good and you're set!
I used the leftover line cord to wire up another footswitch which is in my truck to key my 706MKIIG when I use the headset while roving. The footswitch plugs into the mic jack on the faceplate and the headset plugs into the back of the rigwhich is mounted behind the seat of my truck. The footswitch is mounted where the old style dimmer switches used to be, on the floor in the upper left corner for you youngsters
Hands-free operating while mobile, a BIG plus for safe driving.
I did not include the mic pinout for the IC-746, as others may want to wire this up for other Icom rigs which may not have the same pinout and Ididn't want anyone to take for granted that all Icoms are wired alike. (Click here for a typical Icom mic connector pinout).
See also: G4WPW Microphone Connections Page
Thanks again. If you have any questions or if you find I left something out or made an error, please e-mail me and I'll find out and correct it.
73 for now, Rick Robinson K8DXN
Contents copyright © R. Robinson 2002. All rights reserved.
A. Farson VA7OJ/AB4OJ edited K8DXN's original text, and created this page.
Last revised: 11/15/2012