Jokerz!
Williams, 1988My jokerz has the draw poker flashers and the jackpot ramp flashers stuck on. I checked for a short to ground from wires to cpu. And checked both transistors. They were replaced before I got the machine. Guessing someone got as far as that and pulled the plugs and gave up... any help is greatly appreciated guys!!!
I do not have a logic prob but I can get one. I'll have to try removing that from the board. I'm guessing that will tell me if something is in fact wrong with wiring before that and telling that side of the circuit it should be on??. I'll check when I get home. Thanks for the responce.
Quoted from Kingkool53:I'm guessing that will tell me if something is in fact wrong with wiring before that and telling that side of the circuit it should be on??
Correct, if they go off then its a board problem and if they stay on you have a wire shorted to ground.
I certainly can. I replaced the logic chip that is associated with that section and still same problem. Light goes off when I unplug. It also goes of when I go into testing and only comes on with any flasher call and dosent flash but dimly starts then brighter and then stays on
It's a long time since I worked on a System 11. Do they have the same setup as WPC for driving transistors ? Logic, diode, pre-driver transistor, power transistor ? If so I would be looking at the diode and pre-driver transistor. Also could be a bridged track on the board from a previous shoddy repair.
You need to check U-18 pin 3 for a low signal with the game in attract mode. If this is good then check SR5 pin 3 for a low signal. If this is good then replace the transistor Q-17 with a tip102. If SR5 has a high signal then replace the predriver with a 2n4401.
Yes it is exactly as you said. Wow what a memorie. I'm gonna get on that. What do you need
Mean by low signal. Referring to voltage ? I shouldn't have any voltage on that part right? Or do you mean check with a logic probe witch is still on its way in the mail
Also can't say I've seen a tip 102 transistor. Is there a different part number? Can seam to find it in my parts just checking to see now. In case I need it
My draw poker flashers were out (don't recall any other flashers being impacted though...), replaced Q17 and the associated pre-driver as recommended above and resolved, just fyi. I used a tip102 as well.
From pinrehab: https://pinballrehab.com/1-articles/solid-state-repair/tutorials/120-electronics-tutorial-transistors
Transistor Replacement
In most cases you will be able to find an exact replacement for any transistors. Following are some suggested replacements you should use instead of the original product for improved reliability.
TIP120, TIP121, TIP122, 2N6045 and SE9302 -- replace with TIP102
TIP42 -- replace with TIP42C
13N10L-- replace with IRL530N
22NE10L -- replace with IRL540N
Gotcha very usefully information! So I'm looking for voltage at those pins? Thanks again for the help really appreciate it. The schematic calls for a tip 122 and that's what's in there but I will replace while I'm working on it
Both the jackpot flashers and draw poker flashers are stuck on and the guy before me just pulled the bulbs...
Bingo. Got it fixed. You the man. I read posts from you before and damn your good. I'm just starting to get the concept of board repair. Can't thank you enough!
A low signal is a voltage below .8 of a volt. If you have a logic probe it is a green light. When I do repair work I use a TIP 102 as a replacement part because it is 60% stronger than the TIP122. Now do the same testing on the other flasher circuit as they are the same type of circuit.
All 100 percent man thanks so much. There was so many hacks but so rewarding. Can't tell you how much I appreciate it
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Hatboro, PA
Leeds
