Batboard

I cant seem to get the GE MVS to work with the maxtrac 16 pin. The Maxtrac wont key the MVS and vice versa. I switched pin 8 to COR still nothing i then hooked to another maxtrac and it wont key either way is it something simple I am missing? did all this link said to---http://www.storm.ca/~nand/990/RICK/rptr.pdfThanks in advance
Brian kc2pkk