Did you fit the transist screw underneath to clamp the 'typing unit' to the base pan? If not, then I'll bet the typing unit has jumped off its rubber mountings. If you're lucky, all this will have done is caused the kyboard linkage to get stuck in the key-pressed state, and refitting the typing unit properly will get the machine back to rights. If you're unlucky, you'll have mangled some of the linkages in this area (front right of the typing unit, and the same area of the keyboard) and you'll have some sorting out to do. The basic typing unit has a bare solenoid for the RX input. The Teletpye priveate line call control unitinterfaces this to a 20mA or 60mA loop. Your board _might_ be an RS232 converter, it might be a current loop converter, it might be almost anything. I cna't believe it's that complicated, so you could trace out schematics. Not that common, but not unheard-of either. One of my ASR33s has Data Dynamics electronics (and a Data Dynamics all-metal cabinet, with light bulbs to illumnate the printed paper, etc) which provides both current loop and RS232 interfaces (with the right cable). Of course many companies fitted reader-control relays (DEC, Intel, HP, etc), but generally those were an add-on to the Teletype private line call control unit. -tony