The keyer appears to be Iambic Mode A. Does anyone know if it can be changed to Mode B? A mode A keyer completes the element being sent when the paddles are released; a mode B keyer sends an additional element opposite the one being sent when the paddles are released. You can tell the difference by squeezing out a letter 'C'. With mode B one stops squeezing the paddles after hearing the second 'dah' but with mode A one must key the final 'dit'.