Phone modem

[Wix]

What sort of modem do standard phones use?

[4candles]

Er, why would a phone need a modem?

[rojash]

Phones don't use a modem, cos' they are analogue devices, the purpose of a modem is to convert a digital signal to analogue in order to send it down the phone line (a medium that was never intended for such a purpose).

[Wix]

I know phones use some sort of modem to dial the number and connect, but i've searched and i can't find any info.

[Postdog]

That because they don't!

[Wix]

Well whats the thing that connects to to the other phone through the exchange? How does it send the data?

[markysngc]

a phone cable works in the same way as a speaker cable does on you stereo system it is simply sending an electrical wave with an amplitude (hight) of the wave being changed by your vioce.

there is NO MODEM

http://communication.howstuffworks.com/telepho ne.htm

[4candles]

"How does it send the data?"

What is this data?

What other phone?

[fo3nix]

Check out the first paragraph specifically here:

http://en.wikipedia.org/wiki/Telephone

And the article on DTMF signals.

http://en.wikipedia.org/wiki/DTMF

[4candles]

Hi fo3nix

Your point is...?

[fo3nix]

My interpretation of the question was how telephones connect to each other, through exchanges, etc. DTMF etc. has something to do with this.

[4candles]

OK fo3nix, I see where you're coming from, I think.

One could view the exchange as a sort of modem, except of course it's doing the opposite, converting analogue to digital at one end and digital to analogue at the other.

DTMF is a voice-frequency analogue signal.

Hopefully Wix will re-post and explain what he meant ;-)