> Does anyone know for sure that its safe to simply use the key the IC-706 directly from pin 17 without going through the transistor switch?
1. You can invert the logic by swapping the transistor's base and emitter leads. 2. Anecdotes that don't necessarily apply to CW keying: I've inadvertently sent the PTT and FSK signals to the 706 without a transistor switch, and it worked, except the PTT was inverted. I also routinely send the fsk signal to a 706, 1000mp, and PROII with only a 1K resistor in the line. I originally saw this suggestion in the documentation for the RITTY program by K6STI. I wouldn't say this was safe unless you really understand the schematic of your rig's various inputs. I don't know anything about the CW input - FOr CW, I use a 2n2222 switch with emitter to ground, collector to key, and base to serial port DTR thru 1K resistor. The switch is the way to go - just invert your logic if backwards.