This one was much easier than the 5200 adapter. In fact, it's got me rethinking the 5200 adapter (again).
Thanks go to #rgvc's resident tech wizard, Kevin Horton, for some preliminary guidance. It's not a terribly complicated device, but he saved me a bit of wear and tear on my own noodle.
Cutting up a Sega controller extension cable can give you both the connectors, and a lot more breathing room than you had with the coiled cord on the standard Vectrex controller. The Vectrex controller port is deeply recessed, and it's shaped so that the extension cable may not fit properly. I had to trim a bit of material off the lower corners cable's plug so it would fit. Works great!
9-pin male D-sub connector on the console.
9-pin female D-sub connector on the joystick.
________ 1X0 |1 \/ 16| VCC 1X2 |2 15| 2X2 1Y |3 14| 2X1 1X3 |4 13| 2Y 1X1 |5 4052 12| 2X0 /EN |6 11| 2X3 VEE |7 10| S0 GND |8_______9| S1
Connect the +5V and GND pins of the port and controller directly together.
This provides the proper voltages to the direction DAC's
The standard stick has provision for two buttons. The Vectrex has four. What do you do about this? So far I don't have much of an answer.