We had one of these when I was a kid in the late 1970s. My dad built what was essentially a modem and used it to connect the teletype to an old Motorola single channel radio with a crystal tuned to the amateur radio (Ham radio) teletype repeater in Dallas, Texas. There was a community of Ham radio teletype (RTTY) users in Dallas with similar setups that formed what was essentially a chat room. There was even one Ham that had a PDP-11 minicomputer connected to his system that acted like a chatbot. You could send a message to it to get weather reports and a few other interesting functions. When I would come home from school each day, I would find several feet of paper had come out of the teletype, and I would scan it to see what had been said while I was gone. If I wanted to contribute and the channel was clear, I would flip the transmit switch and start typing. Everything I typed would appear on all of the other rigs that were connected.<p>We could also connect the modem to my dad's HF radio and chat with RTTY operators all over the world. I would spin the tuning dial until I heard the distinctive RTTY tones. I would adjust the tuner until the pitch sounded correct and then turn on the teletype. Often garbage would come out until I got it tuned in perfectly, and then I might see someone calling to start a conversation, or a conversation already in progress. Sometimes I would catch a teletype art (ASCII art using 5-bit Baudot code) picture in progress. If it looked interesting, I would stay tuned in case they repeated the transmission. This took a while because these machines operated at 60 words per minute (~6 characters/second).<p>After a while, my dad upgraded to a Model 19, which had a paper-tape punch and reader. This allowed me to create my own teletype art, so I worked several hours creating an R2-D2 that I was very proud of. I sent it to several people and was thrilled one day when I was tuning around and recognized my R2-D2 being sent by someone else.<p>When my dad later brought home an Apple II, he was able to connect the Apple II to the modem, so we replaced the Model 19 with a Model 28 RO (Read-only), which did not have a keyboard or paper tape, but that was okay because we used the Apple II. Because modern computer printers like an Epson MX-80 were rather expensive then, we used the teletype as our printer, and I even turned in some school papers printed on the teletype in all-caps on yellow paper torn off from a roll. (I'm sure my teachers loved that.) When we eventually did get an Epson printer, it was hard to justify keeping the bulky teletype, so it was sold. We still did some RTTY now and then on the Apple II, but it wasn't quite the same as having the teletype machine left on all day. Of course, most of the rest of the RTTY community was also moving to microcomputers, and the hobby began to rapidly change. Then I went off to college to study computer science and haven't done much with amateur radio since then.