Switching out a classic power supply with new updated one...need help....

tspranger

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Switching out a classic power supply with new updated one...need help....

Hey guys, well i am a newcomer to these arcade game, i was given a old 1979 electro-sport draw poker machine....its just old...i fixed it up with some new micro switches and bulbs...it works great...as i was searching for info on the machine i found a new version of my same machine in my area...i picked it up for 25 bucks....the monitor wasn't working on it. Its the Electro-sport 1983 draw poker machine. I downloaded a manual for it to get all the specs. Well, i started ripping it apart to find the power supply not even screwed to the cabinet....so when this machine got moved, so did the power supply. In this machine it was power supply/audio amp. I have MANY voltages going from this transformer to the audio amp. i have... 5v,8v,10v,12v,16v, and 2 supplys of 115v. I tested them all and found out the monitor feed was open.

Well, i want to replace this very old supply with a new updated on as i know alot of people say that a bad ps can cause havoc. Well looking at my diagram for wiring, i found the wires going to the pcb.

i got:

pin 1: +5v
pin 2: +5v
pin 3: Lamp power "A"
pin 4: Lamp power "B"
pin 5: n.c.
pin 6: n.c.
pin 7: Sense/reset
pin 8: GND
pin 9: Audio signal
pin 10: GND
pin 11: Lamp ground
pin 12: Lamp ground

I know the new supplys have 5 and 12v...i have a couple qeustions on it...on my pin out i have 2 supplys of +5 volts...why? Can i just jump a 5v to each out and just use the one supply from the new PS?

Also, on my lamp powers. Right not they measure 6vdc on both pins to gnd. But when the machine is on, some bulbs work and some act like they are needing power...i think i am only getting like 1.5vdc to the bulb on some...power supply?

I also am confused on the voltages i get when i test it from the lamp powers to GND...and then Lamp ground...going to ground i get 6 volts...going to lamp ground i get 16vdc? Why is that?

And if i get a new PS can i just use a jumper to power A and power B lamps?

I am just confused about the differene in lamp ground and GND....

And what is a Sense/reset?

Thanks for ANY help that anyone can give....

Tom
 
Hey guys, well i am a newcomer to these arcade game, i was given a old 1979 electro-sport draw poker machine....its just old...i fixed it up with some new micro switches and bulbs...it works great...as i was searching for info on the machine i found a new version of my same machine in my area...i picked it up for 25 bucks....the monitor wasn't working on it. Its the Electro-sport 1983 draw poker machine. I downloaded a manual for it to get all the specs. Well, i started ripping it apart to find the power supply not even screwed to the cabinet....so when this machine got moved, so did the power supply. In this machine it was power supply/audio amp. I have MANY voltages going from this transformer to the audio amp. i have... 5v,8v,10v,12v,16v, and 2 supplys of 115v. I tested them all and found out the monitor feed was open.

Only the monitor? Does it take AC? I say bypass the power supply, wire an iso transformer or step-up/step-down (whichever would be appropriate) directly to the power input / power switch and run the monitor off that. If you still have issues, then mess with the PS.

Well, i want to replace this very old supply with a new updated on as i know alot of people say that a bad ps can cause havoc. Well looking at my diagram for wiring, i found the wires going to the pcb.

i got:

pin 1: +5v
pin 2: +5v
pin 3: Lamp power "A"
pin 4: Lamp power "B"
pin 5: n.c.
pin 6: n.c.
pin 7: Sense/reset
pin 8: GND
pin 9: Audio signal
pin 10: GND
pin 11: Lamp ground
pin 12: Lamp ground

I know the new supplys have 5 and 12v...i have a couple qeustions on it...on my pin out i have 2 supplys of +5 volts...why? Can i just jump a 5v to each out and just use the one supply from the new PS?

You can probably just connect one wire to both +5 pins, but make sure you're using large enough wire for the current draw. When there's more than one pin for a voltage, that means the designers expected to draw more current than a single pin can take.

Also, on my lamp powers. Right not they measure 6vdc on both pins to gnd. But when the machine is on, some bulbs work and some act like they are needing power...i think i am only getting like 1.5vdc to the bulb on some...power supply?

I also am confused on the voltages i get when i test it from the lamp powers to GND...and then Lamp ground...going to ground i get 6 volts...going to lamp ground i get 16vdc? Why is that?

And if i get a new PS can i just use a jumper to power A and power B lamps?

I am just confused about the differene in lamp ground and GND....

Don't bother comparing lamp power against (logic) ground... go to lamp ground for all measurements; they're almost certainly isolated from the +5v / logic ground. Measure again with your meter set to AC, measure Lamp power to lamp ground; sometimes they run the lamps off of AC. If they split out the lamp ground, it's either AC, or they wanted to separate the lamps from the logic supply for some reason (line noise?).

Btw, remember, if multiple lamps are wired in series they act like a voltage divider... that is, if the wire goes +V -> lamp 1 -> lamp 2 -> ground, and both lamps are the same resistance, then the voltage between lamp 1 and lamp 2 will be half +V. (If you're not familiar with voltage dividers, now's the time to learn; this is a pretty good primer.)

You can probably use whatever voltage you want for the lamp power, as long as the lamps you have installed are rated for that voltage, but do your math and make sure you don't exceed the current draw of the original lamps, or you could let out the magic smoke.

And what is a Sense/reset?

Almost certainly some kind of logic / power supply control signal... which raises more questions than it answers. What voltage? What does high mean? What does low mean? Is the game signaling the PS or the other way around? It's worth your time to measure where this wire is at at different times... then disconnect it and see where it is on the logic board, and where it is on the PS. A logic probe will be useful.
 
Thanks for the tips roothorick.

I actually just bought a new power supply for my +5 and 12v's...and also found a 8volt transformer for the lights...all rated to where they should be(in amps). I've also bought the cga to vga converter so i can put my spare 13in lcd in.

Still going to do some more testing.

Thanks again.
 
Well, i took some more measurements while the machine was all hooked up.

At the PCB power connector, i am getting 4.5v on both power(+5)legs..( too low right?)

And on my lamp power and ground i am getting 4vdc. When the board isn't connected i am getting 16.xx vdc on the lamp side and 5.1vdc on the main board power....

Should i suspect the power supply? Or could it be the acual pcb itself....

Tom
 
hey tspranger, I realize this is a long shot since this is an old post.

I have picked up one of this machines, someone dropped in on my lap for nothing. any chance you could email me the documents you have for it? or point me to where you found them? I cannot find the manual at all online.

or anyone else? know where I can find this?

Thanks!
 
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