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Need to build a silly volume control for mono home telephone headset...

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pcumming

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I have a home phone handset with a 2.5 mm jack. I like to use a headset for longer conversations.

Headset is mono (one earpiece) with a microphone attached. The 2.5 mm jack is mono and thus has only 2 insulation/separation rings on it.



I would like someone to build a small volume control for me that controls ONLY the earpiece volume (not mic).

Why? Earpiece volume is too loud regardless of headset used. When I crank the phone volume headset down to its minimum it is still too loud. This has occurred with 3 different pairs of headsets. Even bought a Plantronics headphone with a volume and mic control built-in. Problem with that item was that somehow they cut the gain on the mic so people had trouble hearing me.



So: I envision a small box with a pot on top (of some ohm-age). 2.5mm female input and output jacks on both sides of the box.



This must be tested with a mono headset with a mic. You could test perhaps with a cell phone if it accept a 2.5mm jack or a home phone handset. Testing with a pc game headset will not work since that is stereo.



****I could build my own if someone were to suggest the correct ohm-age pot (I have no clue), a suggested suppliers with links, where I might find a small case for the pot, etc... I can of course get the jacks anywhere.



Thanks so much
PC
 
Well if you put the pot in series with the headphones you could use a 5k radioshack pot or pretty much any pot you like. i would go with the 5k radioshack pot. It might roll off the high frequencies but there is no sound above 4k or so on a phone line anyway.

Use one outer pin and the middle pin of whatever pot you like. I would go for 10k or less though because not all pots truly go down as low as you want.

Another method is to connect 2 220 ohm fixed resistors in series across the headphone output, and put the headphones across the resistor that is connected to ground. This will reduce the voltage by exactly half without needing a bulky pot somewhere.
 
Thanks eternityforest,

Some good ideas.

If I go with the pot idea, I read that for my single gang use the pot has 3 connections. Can I use 2 and omit the ground?

I ask because I think am guessing though) that the 2 grounds in the 4 wire cable might be shared between the headphone and the mic. Not sure but perhaps you can add something to this.

And I do not think there is such a think as a 4 connection female 2.5mm trs jack, since the the male jack with 2 collars. But I swear there were 4 wires when I cut the cable. 2 looked like unshielded grounds but were a different thickness.

A reminder there is only one headphone for one ear (not two).

Thanks
Peter
 
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