Hi, Ok, you seem to have a third party controller in your LA36. Because DEC build a real heavey-duty construction for the LA36, and let it print only with 30 cps. many people and some companies thought it could do much better. The few companies mentioned before put to the market several replacement- controllers, making a LA36+ (mpnc) with a much better performnce, sometimes 150 or so cps, loadable fonts and/or pixel-graphics ect. The many people bought those controllers and integrated them into their LA36'es and DEC-Fieldservice didn't got tired of telling anyone that a terminal upgraded that way would certainley disintegrate into its atoms "whitin months"... (I've never seen this happen). These 3rd-party controllers would completeley replace the original DEC-made logic board that was attached to the innerside of the back-door, and was about just as big as that door itself. (mpnc = my personal naming convention) So the DEC printset won't help you much with this, you should find a manual of Datasouth, to get details on the dip-switches. (most likeley they set the baudrate, and the switch in the keyboard has maybe got some other function. That should be possible, 11/10+05 have only 20mA cuircuits. The 11/05 computer is always the active party (=supplying current to the loop) on both Tx and Rx. The baud-rate is made by a rather unstable pair of one-shot monostables. Use a osscilloscope to set the time of this to either 26 or 35,5 microseconds. You need 26 us for the selection of 150 (tap5) - 2400 (tap1) baud, or 35,5 us for 110 baud on tap5 of the swich. I think, thats normal, afterall when the terminal is idle, there will be no current flow. Put your multimeter into mA-mode, and put it in series into the loop. Use preferably a cheap passive arrow-meter, the cheaper it is, the better the measurement. Alternativeley, you can also put a led somewhere in the loop. create data-output, and see what happens Seems ok to me. (long time ago...) (Beware however that the naming-conventions for ths 20mA current-loop were not always consistent. There is no industry standard for this. I dont know how Datsouth has named its connection-terminals) If all this is ok, still nothing will happen if the baud-rate is unmatched between 11/05 (rotary switch and trim-potentiometer on M7260) and probably dip-switch and/or Keyboard-button or keyboard sequence on the LA36+ Ack. Ack. Hope you can solve this. Frank