Setting up my TS-790A for Packet Radio

Packet Radio is a digital operating mode based on analog FM (frequency modulation). First of all, you can establish a direct link between your station and a packet radio digipeater, which is basically also such kind of a station. Most digipeaters are interconnected mostly with microwave links, making up a word wide network. The routing protocol used for it is AX-25, an X25 variant for the special amateur radio purposes.

Packet Radio is a very early radio based digital network with its roots way back in the 1980s. In those days, 300 bit per second were really speedy. Today, 9k6 or partly 19k2 bit/s are good transmission speeds. Sure, nothing spectacular, you will say, looking at your 108 MBit/s WLAN router. That's very true, I need to admit, bit it's still an interesting technology, because you can learn a lot about digital operating modes. So what do you know about your wonderful WLAN router? How does it work? Hmmm? Yes? I'm listening!!

Let's have a deeper look inside.

Terminal Node Controller

A TNC is a little more than a modem. It is a modem, but there's more to it. Think back to your old 14k4, 28k8, 33k6 or later 56kBit/s modems. They were only used to establish a digital connection to the link counterpart and to transmit single characters. So in a ISO/OSI sense they were only good for handling the physical layer and the link layer.

more to come...