I am using a vintage TG Products Joystick on an Apple ][. 1978 Rev 1 motherboard with 16 PIN DIP gameport I/O.
Both fire buttons work but the joystick stick movement does not produce any movement on the screen (not even a jerk)
Tested with Pacman, Centipede and Defender.
When I opened the joystick unit the internals seem minty clean. Just two pushbuttons and two potentiometers with mechanical trim adjustments.
Output is a 16 pin DIP plug with all legs OK. I have a pin-out for the gameport I/O.
Have you come across a similar situation
How should I proceed to further diagnose and if possible resolve this problem?
Where can I find a joystick test program? (I don't have the ability to download disk images at the moment)
Anything I can check with a multimeter?
Thanks for the help.