Model 40x Wms: Reel_1 error, U shaped optos - repost

[cfh]

from the old NLG site...

So i figured while i'm looking to buy the ROMs for the dotmation
"Stroke of Luck", i should at least try and get the game running
with other firmware. So i put in some EPROMs and do a CLR
("Change Game 2" error), and I notice that reel #1 (aka the "A"
reel, far left as facing the game) does not stop spinning like the
other two reels.

The game gives a "reel_1" error on the red LEDs below the
reels. So i swap reel 1 and reel 2 to see if the problem travels.
Sure enough it does. So i know the problem is the actual reel itself
(and not a board problem).

Next i look at the LED on the reel board. It should be
"off" except when the reel interruptor goes through the "U"
shaped opto (blocking the infrared light and making the LED
go "on"). But the LED is always on, no matter if the U opto
is blocked or not.

Next i put gentle pressure on the .100" connector to see if
the LED state changes. Often the solder joints on these single
sided boards crack, giving intermittent connections. No suck
luck. Likewise i "tweak" the U opto a bit and YEA, the LED
goes out for a second. I have found the problem.

So i remove the opto board from the reel assembly, and
resolder the opto leads (and the .100" male connector
pins, since i have the iron out). i hook up the board (without
the reel motor/assembly, and block the U opto with a screwdriver
blade. but no love! what's the deal?

Next i remove the U opto from the board (that is i desolder it
using a desoldering tool), and "split the case" on the U opto.
The U opto has a plastic case that holds a receiver and transmitter
LEDs. with the case off, the two optos are exposed and easier
to diagnose. i can see the problem. The transmitter
opto is cracked. My gentle pressure on the opto just pushed
the two cracked halves together making contact. that crack
will pretty much kill the opto, need to find a replacement.

So next up is to find a replacement U opto, or just replace
the entire reel assembly. i'll do what ever is easiest.

(I thought i would convey this diagnostics, incase anyone else
has a similar problem.)