Can You Convert a 2.5mm Phone Jack to Dual 3.5mm Jacks?

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DaveC426913
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My cordless phone (No not a cell phone, this is a landline. They still exist, you young whippersnappers.) worked with a head set thus:
http://www.maxiaids.com/ProdImages/9700750.jpg
which has a 2.5mm jack. (It looks like a stereo jack i.e. three contacts but of course, it won't be stereo, it will be speaker and mic)

I wanted a smaller, lighter headset so I bought something like this:
419083H1JVL._SL500_AA280_.jpg

Problem is, it has two jacks (one for speaker, one for mic, colour-coded pink and green) and they are 3.5mm (and also three contacts).

I don't have a problem converting from 3.5 to 2.5, my difficulty is converting from single connector to this double connector. Clearly I can't simply use a Y-connector, since all that will do is feed the speaker and mic lines into each other.

Is there an adapter like what I'm looking for? What can I do?
 
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They didn't sell a headset compatible with your phone?
 
Chop the 2.5mm 3way off the old headset and solder it to the wires on the new headset?
 
the new headset is for a PC. On most sound cards, the inputs are also colour coded (pink and green) for mic and head phone 3.5mm jacks. This headset, as far as I can tell, was not intended to be used with a landline telephone. Using an adapter won't cut it I don't think. Still got the receipt? :wink:
 
redargon said:
This headset, as far as I can tell, was not intended to be used with a landline telephone. Using an adapter won't cut it I don't think. Still got the receipt? :wink:
I don't see why not, the microphone is going to be a standard electret and the headphones are all the same.

ps. the 2.5mm plug is normally microphone on the tip, then headphone then ground.

http://ca.geocities.com/mstudi@rogers.com/retro.html
 
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They didn't sell a headset compatible with your phone?
They do but not the type I wanted. I was optimistic about thinking it would be a simple matter of finding the right adapter.

mgb_phys said:
I don't see why not, the microphone is going to be a standard electret and the headphones are all the same.

ps. the 2.5mm plug is normally microphone on the tip, then headphone then ground.

http://ca.geocities.com/mstudi@rogers.com/retro.html

Thank you. That is exactly what I needed. (Failing finding a pre-made store-bought one that is...)

OK, only one issue left. The green/pink connectors are also 3 contacts, which means I have one contact each too many. Why would a mic connector have three contacts? And why would a single earpiece have three contacts?
 
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DaveC426913 said:
Why would a mic connector have three contacts? And why would a single earpiece have three contacts?
Either there are two microphones - one facing toward you and one away so it can do noise cancellation - OR they used stereo plugs because they are more common and cheaper.