Modem
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Modem
In order to send and receive email, your computer needs to send and receive a series of ones and zeros. This is called "digital data" and can be used to encode emails, GRIB files, pictures, etc -- basically any piece of data that your computer can handle all comes down to ones and zeros.
Propagating through the atmosphere, travelling through wires, and in many other places, there are electrical waves of various types. These are often "analog signals", for example music or voices that you hear, HF radio signals, satellite radio signals, etc, are all examples of analog signals.
A modem (short for "modulator-demodulator") is any kind of device that converts digital signals to and from analog signals. Modems allow your computer to talk to other computers over long distances. Even when you think that there are digital signals travelling directly to and from your computer (e.g. ethernet, wi-fi), these are in fact all modulated over analog waves travelling through wires or through the air (or through space).
Different types of modems are relevant at sea, but the main ones are:
- Pactor HF radio modems
- Satellite phones
Note that other types of modems exist -- the old style telephone modems, ADSL modems, etc, but these are outside of the scope of this article.
We don't normally refer to a satellite phone as a modem, but in fact all satellite phones are capable of operating as modems for sending digital data as well as making regular voice calls.
Installation and Setup Details
Also see the Email at Sea page.
Description?
References
Publications, etc.
Forum Discussions
List links to discussion threads on partnering forums. (see link for requirements).
External Links
Personal Notes
Personal experiences?
