Bally 742 fuse blowing problem

[Rgull77]

Four switches. I'd have to trace all eight wires?  I like your idea about just testing the function of each switch better. I jumped every wire top and bottom to the 'insert coin' light and the only one that made it go on and off when it should was the yellow/red tracer wire on the 3rd switch. It appears to transend two switches. Actually, maybe there are 5 switches. That switch on the very top out of camera view is open at rest. So the yellow/red tracer wire is connected to at 3rd switch, closed and the 4th switch, open.

I'm ready to give up. The machine works, the light is just a pesky problem. How do I safely check the voltage to the coin lockout wire that is currently taped off?

[OldReno]

Hi, I see you already posted while I was writing, but thought I would include this to help you track out your circuits ---

Here are some of the things I think you have on your coin relay stack.  You should have a switch (NC) from the door coin switch (downstroke side).  The other side of this switch should go to your coin relay coil.  This switch shuts off the coin relay coil after it trips so it doesn't burn up.  You should also have another set of switches (NO) going from some circuit (perhaps the other side of the coin in switch-upstroke??)  to the handle release coil.  This NO switch completes circuit to release handle after and only after the coin relay trips off. Keeps you from getting constant free handle.
You should also have another set of switches, one (NC) that lights the insert coin light, along with a center leaf that makes to your (NO) coin accepted light.  This shold be a 3 piece switch, the center leaf is power. The closed side is insert light, the open side is accepted light.
You may also have a set that turns off the coin lockout coil (50v) behind the coin acceptor, but you said you taped it off.
If you have the energy you can trace these out, since I've given you some idea of where they (might) go....
I think there should be the following circuits:
1. Safety circuit to turn off the coin relay coil.(NC)
2. Circuit to activate handle release coil.(NO)
3. Circuit to turn on and off the coin accept and insert coin lights. ( 2way)
4. Perhaps a circuit to turn off the coin lockout coil.(NC)

[OldReno]

It appears your 3rd switch, which lites the light, is the right one.  One side is NC (insert coin), and the other side (NO) should run your coin accepted.   I can't tell how they're wired from your photo, but I bet someone messed with the wiring of it.  That's the one you need to track back from the door, through the plug and into that switch.  Or work backward from the switch to the door, probably a better idea. Anyway, sounds like you're doing ok so far.  It all depends on how 'pristine' you want to make your machine.  If the light is no worry, then don't bother, and put it away for a future project.

[Rgull77]

The way you put it sure makes sense but I know for sure that the uppper yellow wire with black tracer on the first switch (left) goes to the coin accepted light. It doesn't look tampered with because the lttle plastic cover is still there. In any solder work afterwards those seem to be missing.

 So on the bottom of the third switch is the wire that goes to the coin lockout solenoid (this appears to be after work) and the top wire I haven't been able to trace, but it doesn't go to the door. I think that the wire for the insert coin light was used for the coin lockout instead of running a new one for whatever reason. Maybe that's why it bridges the 1st and 2nd leafs on the bottom of the third switch.

How do I check the voltage of that wire?

[OldReno]

Since you already removed one wire from the coin lockout coil on the door, take your VOM on AC volts, and touch one lead to the end of your cut wire, and the other lead to the other wire still soldered onto the coil.  If it reads 50V, then it belongs on the coil, however, if you are fortunate and it reads 6V, then you might want to attach it to your insert coin light and see what happens.
Just make sure that wire is not a solid orange one, which is the 50V feed.
If you can, trace out that other wire the top wire to see what it's all about.
Good work so far....
Actually, never mind the above suggestions, that even confused me....
Your working voltages from the transformer are the Blue (6V), the Orange (50V), and the yellow wire, which is common to both circuits.
All 6V lights, and 50V coils use the yellow wire, you could call it the return if you like.  In order to work there must be a complete circuit back to the yellow wire.  I'd clip onto the yellow wire (probably on your coin in switch), and then start checking voltages on the door.  Be sure you don't mess around with the solid white and solid black wires which may be 120V for your fluorescent lights.
I sure don't know what they did with your light circuits, but it is a mystery.

[Rgull77]

It's 50 volts. But don't the wires on the switch just open and close circuits? The 50 volts is coming from the orange wire. When I use the yellow and the bottom wire I get no reading. So if I run the wire to the light, doesn't it take on as 6 volt and just open and close the circuit? Or is there 50 volt and 6 volt in the stack of switches?

[OldReno]

You can have all 3 voltages in a stack if you want.  Yes.
But they all work independently. And they need to be insulated from each other.
Generally all 50V circuits terminate onto the orange wire.
The 6V lights, bell, end in a solid blue wire.  Both coming from the transformer.
The 120V circuits do not come through the transformer, they take off before. I've found them mostly to be solid white or solid black wires.  Any solid wire like that is probably connected to power supply source than rather through switched circuits, I believe.
No circuits should touch to case (when reading meter on ohms) except for your ground connection from your line in from the wall.  If I have a short, I power it down and check the machine with my ohm-meter until I fix or find the short.
Chasing circuits are a lot of fun, and finding shorts is especially entertaining.
Good on you.

[Rgull77]

Yeah, I saw the flaw in my logic afterwards. If a switch opens and closes a 50 volt circuit, then its 50 volts in and out.

The thing about the 'insert coin' light is that if they were on the same switch, the triple one for example, then the instant the insert coin light goes out, the 'coin accepted' light comes on. Then on the spin, the 'coin accepted' light goes out and the 'insert coin' comes back on during the spin. On my other machines, the 'coin accepted' light does goes out (after start of spin) but the 'insert coin' light doesn't come back on until the end of the reel spin. So perhaps it's switched on the other side of the reel mech. Every wire on the stack seems to go somewhere else so maybe I'm not looking in the right place.

On my other Bally, the 'insert coin' light goes back on at the end of the spin. I'll try to trace that wire, that should give me a clue.

I sure am learning a lot. I really appreciate your help.

[OldReno]

I think your 2way switch on the coin relay is miswired.  Send more pics.
Also check your 'C' stack which is just above the variator.  Push back the variator with machine on, and see if the insert or coin acc lites go out.

[Rgull77]

Nothing happens to the lights but then again, there isn't a wire to the insert coin light. BUT, the grey with red trace wire is on that switch too. That's the same color as the wire on the top of the 2 way switch that I was going to trace. So maybe it turns off on the coin relay stack, but goes back on in the C stack at the end of the spin.

 The top half of that switch (on the C stack) has a solid gray wire coming out of it. I'll have to trace that tomorrow. I can even jump it to the light and see what happens. I'll let you know and I'll get some pictures af both switches.

[OldReno]

I'm thinking your solid grey goes to the 3rd reel board to power the pays.  But I'd need a schematic to tell for sure.  Try ohms check if you find it on the reel board.  I believe that C switch keeps the machine from paying during reel spin, and doesn't close until after the 3rd reel indexes.  Good job, BTW!

[Rgull77]

Okay, I took some better pictures. All the wires on the C stack seem to have other purposes. The solid gray or actually darl brown, wire did go to the bottom of the 3rd reel board, then out to, I assume, the plug. I'm gonna trace the coin accepted wire on my other machine, maybe that'll shed some light. I suppose I should have done that a lot sooner.

Nice fix-it posts. I read them all.

In this picture,on the top I think it said A-B-C-D (Left To Right)

[Rgull77]

I traced the coin accepted wire on my other Bally. Now that I'm done bandaging myself, I can tell you that it's 'insert coin' lights' wire is on the C stack but on a center switch, so thats where it closes to light back up. I don't see the same color wire on the coin relay so I don't know which wire opens the circuit to turn the light off. The top wires on that switch are solid yellow and go to the bottom of the second and third reels. The 742 doesn't have that 3rd switch.....

These pics are better ones from the 742....

[Rgull77]

I have a schematic from the Mead book. It looks like the Coin insert (18-2 Red/Black tracer) and the coin accepted lamp (38-1 Yellow/Black tracer) are wired to the same switch on the coin relay. That would be the switch on the far left. That is where they are both wired on my machine. The problem is that the red/black wire isn't anywhere on the door.

So I  followed that wire (red/black tracer), it leads to the payout relay on the hopper. It's switched with the 48-1 (green/ black tracer) wire which is the same wire on the door that is attached to nothing because what should be the winner paid light is jumped to the general lamp above and is always on. This wire also is the one that lights only during payout if I connect it to a light, it does not stay on until the next pull. So all these wires are related. No insert coin wire and no winner paid lamp.

Any thoughts are appreciated.

[OldReno]

Hi,
Looks like you're doing a great job tracing stuff out.
I will ponder your last post, however here's my thoughts on your winner paid light.
It should be a stand alone circuit, and logically it should go through the payout relay coil switches.  And, it should be through a set of normally closed switches.  This is because during payout, you don't want the light to come on, only after payout when the payout relay turns off and the switches go back to closed position.  Also it should go through a latching switch which is normally located on the rear inside of your payboard assembly.  If you take off the top screw holding your payboard, you can drop it down, and you should see a linkage assembly (which is controlled by your 100 tooth white plastic paygear).  When 1st coin is paid out, this linkage should unlatch and close a switch (which pokes up in the back).  When the payboard resets on next handle pull, this switch should latch open.  this switch is to turn on the winner paid ONLY when the machine has paid.
If you can find this switch and linkage assembly, you should find the two wires you need.  One probably from payout relay, and the other should go to the door, and eventually to your winner paid light.
Excellent job so far, I am impressed with your dedication to this problem.
So, anyway, the winner paid circuit is stand-alone, and the insert and coin accept lights work together.
Hope that helps a little bit, and I'll get back to you....

[Rgull77]

I thought maybe the switch in front of the wiper board, it closes at the start of payout but then the light would go on during pay and stay on. The wires from that switch lead to the board, then a grey/white wire goes to the switch on the other side (top pic). The wire out is the yellow/red wire which goes back to the payout relay. The wire out from that is solid yellow and jumps up to the top switch where the red/black wire is, and that goes to the door.

 If I connect the red/black wire on the door to a light, it doesn't just light continually during payout, it flickers on and off very fast. The only switch that does that on the hopper is the switch on the ratchet side of the pay board in the top picture. I think the light was purposely disconnected. Maybe the hopper has been modified. There's writing on it that says "rebuilt 2/26/78"

I really appreciate your help. I am learning an awful lot...

[OldReno]

I believe the switches on the right are your arc switches.  There's a post somewhere here on those.
It appears you are missing the switch I talked about, but be relieved, I think my modified 742 also is missing that one, and my WP lite also is not right.  I don't have time or energy to fix it right now.  Too much else to do....
You could in theory run another circuit to your Zero switch, but that's sure a lot of work.
I dunno.  Did it ever work right?
Maybe someone can jump in here with ideas, on how these 742's wired the winner paid lights?

[Rgull77]

Nope, It's always been like this. Well, I guess I'll put it on the back burner unless someone else chimes in or you come up with something on that 'insert coin' light.

Thanks Old Reno, at least we fixed that short! When I move to Reno and we are neighbors, this will be a lot easier! Actually my best friend, that I grew up with, lives in Fernley. I used to go up there in the late 80's and stay downtown. I'd go to the Nevada Club and Harold's and Harrahs and play all the mechanical machines. They used to hand pay jackpots in rolls of nickels! Then they installed hoppers and then they all just disappeared. I eventually bought a Harolds Club machine. It has it's troubles too!

I'll be working on my Bally 'Lucky Twins' soon.

Thanks again....
Randy

[OldReno]

Looking forward to meeting you when you move here.  It's a really nice place, lived here most of my life.  Mountains, lakes, desert, just beautiful.  And a great climate.
Anyway, some projects have to be put on the middle burner....
Nice diagnostics BTW so far on your machine.