DBV-35 IN SG-50B

[klclandscaping]

Hi, I just inherited a working SG-50B Slot machine that accepts coins and works fine except for the bill validator. It was unscrewed but in place plugged in with 2 connectors in front and there is no can in it and the 2 connectors for microswitches are disconnected in the back on its DBV-35. I am assuming this validator is outdated for new bills so I am wondering whats my best bet to get it to accept bills. There is a red light inside where you stick the bill but it wont feed in, no noise nothing like it doesnt know you are trying to insert a bill. Is there a way I can dignose this and at least get it to work for older money? Or which unit should and or can I replace it with? Thanks so much in advance for any reply, this was my dads machine he played till the day he died and I really would like to get it to accept bills.