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How-to: Amateur Radio Digital Modes: Page 1
In this article, we explore the fascinating world of HF digital communications. Nowadays, there are many digital modes that do not need an expensive interface or modem. Broadly speaking, it works like this: you buy or build a relatively simple interface to connect your transceiver’s audio to your computer’s audio, then you install some nice software that does all the work of sending and receiving the various digital modes.
The computer and software may also control the radio’s PTT line, and with a little more complex interface (and a radio with computer-control capability) it can also run most of the radio’s front-panel functions. Thus, the transceiver becomes an RF “back-end” for the computer and everything is done with the keyboard, screen, and mouse.
Most of the digital modes are teletype, and using them is like simplex keyboard chat. Other modes can send and receive color pictures, fax, and other types of data. Still others are specialized for extremely weak signals, such as moon-bounce.
One of the neatest things to come along in a long time is PSK, or Phase-Shift Keying. It’s neato because it can provide a good copy with very low power and narrow bandwidth. With just a few watts and a narrow
There is more to digital modes that just the interface and software. We will also explore the various modes in some detail, as well as operating practices and commonly-used frequencies. So let’s get started!