Total posts : 45366
The phone patch I am happy with is a modified Radio Shack Duo 101 Speakerphone, which may no longer be in the catalog. I use it exactly as is, but with two add-ons.
The “as-is” part means that anyone here in the studio can hear the caller on the speakerphone and no one needs headphones. But the radio listener is patched in as follows: I ran a cable out from the speaker voice coil and added a capacitor since I think there’s DC present for some reason. This cable goes to a 1:1 transformer, from the same Company, and plugs in to the audio mixer. On this line the incoming call is perfectly clear and the local out-going voices have been phased-out, so that our voice is picked up by the normal studio mic.
2nd, the speaker phone has a built-in electret microphone, which I disconnected, and ran the mic line out to my own electret, installed in a plastic tube and projecting from my studio mic where it is attached by a yellow rubber-band (any color rubber band will work). In this way the incoming call hears us close-up.
In the past I installed a Symetrix TI101 for a client, and was surprised how (relatively) poor it sounded. I was afraid the client would think I didn’t know what I was doing, but they never complained so I’m not sure what they thought.
