This item was picked up in a home. It's the Jenning's 400 series slot. It's over 25 years old so it's legal here. It uses 100% TTL 74xx chips, motor driven reels, mechanical hopper, and linear power supply. The game arrived 'dead'.
For starters the main pcb was not plugged in and the service key switch was in the service mode. I noticed right away the reset button on the pcb was intentional shorted. I'm not sure why someone would do that.Also, the 5 volt line read 4.5 with ripple on on one of the TTL chips.
I was able to get the reels to spin a payout but very intermittently. These machines have lots of trouble with the edge connectors and power supplies. I saw a piece of black tape on the main 5v capacitor. When I touched it the leg separated from the cap. This explains the 4.5v w/ripple. Replacing the cap ( you can easily do this without removing the power supply ) fixed the problem.
The game spins and pays well now but the reels squeak badly. I wasn't looking forward to tearing down the reel mechs so I did the next best thing and dripped a little 3-in-one oil down the side of the contact plate pcbs and the squeak disappeared. I may rebuild these later if necessary.
The reels themselves are very worn, dirty, and chipped. I'll make new ones later with laminated paper strips. The glass and cabinet are decent - not new - but not damaged. The handle is missing the locking pawl which makes that great mechanical slot ratcheting sound. The handle knob was so loose it almost fell off - glad it didn't. The handle start button is intermittent - the wires on the terminal were loose.
There's some other odd little problems like the coins played lamps being out and the 7 segment LED blinks obscure characters on zero, one, two, or three coins but not on four or five. The hopper pays out fine. The reset switch was bypassed on the pcb which explains why the machine doesn't go into alert mode when the hopper is empty.
I don't know why by almost every older slot machine has nasty, torn, ripped, and/or dirty reel strips. Mine are no different. I'm opting to replace these with new strips. They're easy to remove - just pop them from the edge slot on the plastic reel. They'll probably be glued/taped near the end of the reel.
I made the new strips on a large format printer. These were made to the same dimension and proportion - 22 character positions per reel - 25 1/8 inch long x 2 3/8 inch wide . I wasn't too concerned with creating an exact reproduction. Here's a copy of the 3 strips on one image - this can be printed onto a 24x36 inch sheet or roll media.
The printed reel strips were first laminated and then cut. They came out well. I might have used a yellowed back ground instead of plain white for a vintage look but opted for white. These are rather generic reel strip - single, double, and triple bar with sing seven. There is a small keyway you'll need to trim on each strip - examine the ones you've pulled out and match the location. When put in the machine they look nice.
I was actually happy with how these came out. You can clearly see the yellowed plastic next to the new white strips and the whiter part of the plastic behind the third reel. As this machine was in the Sands Casino in the 70's/80's and was subject to A LOT of cigarette smoke.
More To Come...