Coin mech problem

[wyld_mann]

Hey there! i'm a bit of a noob at this and need some words of wisdom.

I bought a Data East Star Wars pinball machine on ebay a few years ago.  The coin mechanism didn't work at the time but i didn't care.  I was just going to use the freeplay feature anyways.  Now that i've had it awhile, i want to get the coin mech working. The coin mech that is in there is a Sentinel 29, 8 coin validator.  It appears to be shot, as every coin i insert passes through without a sound from the Sentinel. The +12 volts is present.    So, now i'm looking to get a different coin validator to replace it, but not sure what to look for in a new one.  All i really want is one that will accept quarters and will talk with the pinball machine.  I'm pretty good with electronics but i'm not understanding what all of these parallel interface lines are doing on the validator.

For instance, there's a Com A line, 4 Acc lines and 4 inhibit lines.  If i bought a new validator, will these lines correlate with the lines on the new mechanism?  For that matter, what lines would a plain jane coin mech have on it to communicate?   

Before i blew money on something i'm not sure about, i thought i'd call for some help. 

Any insight into this would be awesome.

thank you

[grantspain]

it could be just dirt in the accept gate making it lazy(which is the noise you hear)
a c220 should slot right in but could be difficult to find in the states
the wiring you gives you everything you need to fit any mech whether mechanical or electronic,some electronic mechs only need +12v/ground and a credit line(being any one of the 4 acc lines)
a really easy fix for you is to get a mechanical mech and entry plate and modify your door then you could use coin common and one of the acc lines to the coin switch

[wyld_mann]

what do you mean by coin common?

[grantspain]

what do you mean by coin common?

on the sentinel they had 2 commons-1 for the +12v and the other for the coin accept lines.there should be label on the side of the mech numbered 1 to ? with a1/vcc/com/ccom etc do you have that?

[wyld_mann]

OHH.  Yes there is a Com A line.  So, on a new mech you'd just need to use an ACC line, the COM A line, ground and +12 volts ?  What exactly are these lines doing anyways.   

[grantspain]

if you used a mechanical mech then you use the com a and one of the accept lines
com a is the coin switch common
acc is the +12volts
ground is the voltage common
all the a1,a2 etc are the coin accept switch lines a4 being the lowest value coin
all the i1 etc are the inhibit lines for each coin
i could really do with a pic of your mech so i can without doubt id the correct pinouts

[wyld_mann]

Here is the sentinel.

[grantspain]

i think your best bet is to get this mech repaired as it only probably needs recalibrating,a couple of things to check first to prove its the mech at fault
+12 volts is good
all the acc lines at around +5 volts
all the inh line at around +1 volt
if all the above check out then its almost certainly the mech at fault