I've just whipped up a schematic using some fancy CAD software.....
I am wondering if my problem lies with the "-" speaker input - does this need to go to the earth for the potentiometer?
Yes, did some mucking around with an old radio 1st.
Currently i am using a 12v battery sponsored by work as a power supply, but intend to use the 12v source at the coin door interface board (from an Indiana Jones - some other guy has done this (
http://www.edcheung.com/album/album06/Pinball/ij2.htm - at the end of the page).
**Just looked at my diagram and the pot numbers should be reversed ie: 3 at the top and 1 at the bottom**....dodgy software!!
