The universal keying module will key your old Heathkit DX-20 or your Drake 2NT that uses grid blocked keying.
You can configure the universal keying module to key either grid blocked or cathode keyed radio. Today, all radios key by pulling their key line to ground. This is the same as cathode keying.
The universal keyer can also key some HF amplifiers. Their key lines must be positive. This includes the Heathkit SB220 and most of the newer amplifiers. This module will NOT work with the SB200 or the Collins 30L1.
The kit consists of the PCB and all components. There is no case included with the kit. Generally, there is more than enough room to install the PCB inside a radio. If not, a small plastic box from Radio Shack will work just fine.
The price for the kit is $15 +$3 shipping.
QST corrections
Some bugs got into the QST article.
Q1 is a PNP type transistor. It’s a 2N4403
U1, pins 1 and 2 are swapped. Pin 2 should go to the “key in “ pad.