Computer parts


The Modem

Modem is an acronym for modulator/demodulator. It modulates the digital signals in the computer, that is: makes analog signals out of them), and it demodulates the analog signals from the phone line, that is: makes them digital.

A modem is needed for everything the computer does via telephone line, e.g.:
  • transmitting data to other computers,
  • dial-up connection to the service provider (internet access),
  • sending and receiving faxes,
  • running phone and answer machine.

For the latter two tasks a so-called voice modem is needed - not all modems can handle voice data.

Elsa Microlink
	 56k internal modem
Elsa Microlink 56k internal modem

Modems can be connected internally (via ISA expansion slot) or externally (via serial port). What way you choose doesn't matter much.
The speed of the modem does matter, though. Modems are nothing new to the computer sector, they have been in use for decades. Accordingly, there are outdated modems with 1200 or 2400 Bit per second, old modems that transfer 14.4 KBit per second, and modern ones that can handle 28.8, 32.6, or 56 KBit per second.
For the voice functions (answer machine, fax) a 14.4 modem is fast enaugh while for any kind of data transfer it should be at least 28.8.


© 2000 Peter Gallert, last updated on 4 April 2001