I have a PC Engine one, there are a few different ones, and yours is more or less the unofficial knock-off one. The 1st series of pics, with the harness, shows it was adapted to work with a TG and to work in a cabinet that may have been giving sync issues because of the +5/-5 line in addition to possibly working in an early or hacked up jamma cab. To use a TG instead of a PCE is really just switching a few wires around. There is a play timer which can be disabled with the dipswitches as well as attract sounds. It is 1 player only but hook a tap up and 2 player works on any 2 player simultaneous game just fine with a regular controller. You can wire 2 player controls thru the jamma harness by hacking a controller up. 6 button is possible on 1 and 2 player if you add some wires. Adjustment pots are for volume, brightness and RGB. I also added turbo switches to mine for both players. You are looking at about $25-$45 tops with no system included. Although uncommon, not really valuable, but cool as hell.