What does a condenser do in a phone?

[CDK]

Can anyone please explain in detail what the purpose of a condenser, and what it's function is in a phone?

[Owain]

A condenser (capacitor) blocks direct current (DC) and passes alternating current (AC).

The usual use in a phone is in the ringer circuit. The capacitor passes AC ringing to the bell, but prevents the bell passing DC and looping the line causing an off-hook condition.

[ThePillenwerfer]

There's also a smaller one which was introduced after the advent of radio to stop the transmitter working as an ersatz crystal set.

A condenser presents an infinite impedance to DC (or it does in theory) but a lower impedance as frequency increases.  The one mentioned above will short out radio signals but not have much effect on lower audio frequencies.

[Fabius]

The condenser in a telephone condenses all the sound waves that the speaker makes into compact analog data packets in a size small enough to travel through those small wires. On the receiving end the de-condenser restores the sound waves to their original size.

[Babybearjs]

why would you want to condense sound waves? wouldn't that make it hard to hear?? Microwaves.....

[LarryInMichigan]

why would you want to condense sound waves? wouldn't that make it hard to hear?? Microwaves.....

It helps when you speak to a customer service rep or other people who are dense


Larry

[Fabius]

why would you want to condense sound waves? wouldn't that make it hard to hear?? Microwaves.....

It;s to make them smaller to fit through the wires. The un-condenser at the other end restores them to their normal size.

[TelePlay]

CDK hasn't logged in since he asked the question so I hope he gets the humor after the facts.

BTW, isn't there also a capacitor in the some talk circuit making 3 possible capacitors in a phone plus the coils - 1) ringer circuit. 2) talk circuit and 3) the static/noise suppressor in the base of a D1 or in a handset cup?

[CDK]

That is so freakin hilarious lmao!!!

[19and41]

They are usually used to quell spurious noise on the line .  That also is the principal use for them in radio and audio equipment.