The A1200 has composite built in. So should any crt tv built in the last 15 years. Look for the yellow plugs on the A1200 and the TV. Connect the two with an RCA plug.
Then hold down both mouse buttons on boot up
A menu will come up. Choose boot with no start up. A default CLI screen should come up. type loadwb. workbench in 4 colors should load up. Go into sys :prefs/screenmode and select the right screenmode for your tv.