Touch tone pads and the like...

Ethan Disck Wrote: Yes, there are a couple of different Touch Tone Pads floating around. The main difference between them is a couple of things. The ones with more wires are designed for use with SpeakerPhones ("List 3" and the like for those reading BSP's at home). The extra wires do a couple of things. One set mutes the speaker a bit (an extra set of contacts) when dialing so you won't get blasted with the tones on the speaker (normal use is to really send LOUD tones down to the central office). The other wires provide power to the oscillator when using it "hands free". Normal power is derived from the telephone line, but with speaker phones, it is a bit different. Hopefully this will explain things. My problem is that I have a couple of "solid state" (non-coil) pads (they use an IC) and they are only compatible with non speakerphone telephone sets. Here at my parents house, they have three 2565 sets, one which is with a speakerphone. I would like to replace the old single transistor L-C pads (they turn on tones a bit mushy) with more modern ones, but they don't have all the wires. One of these days I'll figure out how to make do. Ackk! another "project"...