A critical missing piece in the original docs is the driver stage. The repack includes a standard NPN transistor (2N2222 or BS170) circuit to key the transceiver:
However, there’s one consistent complaint: k3ng keyer schematic repack
: Use a 2N2222 or similar NPN transistor to switch the transmitter. Connect a 100-ohm resistor to the base lead for reliable switching. A critical missing piece in the original docs