Newcomer here, 60 year-old jack-of-all-trades, master of none...
Picked up this Brunswick Alive cheap...it was working in a little country store and suddenly quit.
On the Board I found a resistor (half of one) lower right corner, beside 7815 regulator, and showed signs it had burnt. And no way to identify it...Recently I picked up a dud board from Steve at PR, and it had the resistor in place. I figured it to be 5.1 ohms at 5% with an online calculator. (Hmmm don’t know the wattage—guessing 1 watt maybe)...no time lately to try that out...
In the meantime, something had me digging into the overall game schematic (as we know none seem to exist for the board) and was curious about the supply transformer. Breakers are all loose and such—just done feel right. Anyhow, I took measurements of the outputs and it seemed it was bad, but I read from many posts that almost never happens. Couple more times it seems I’m getting some other readings. (Not very smart me doing the typical—one probe on the yellow Common lug, and the other probe on each output of 2.7v, 6v, and 27v lugs after I desoldered the unit away from everything else) I’m going to put it back in and try measuring at other points...
Question: What’s with the “-6v” lines and such I’m seeing in the schematic? Is it feasible to replace this unit with more traditional power supplies and get rid of the associated rectifiers?
I’ll attach schematic views...
Thanks for any guidance.
Tim

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Here is pic of the dud board with that resistor in case someone would need it...
Bands are Gold, Gold, Brown, Green

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Thanks guys...billc479 about my power supply question, I was thinking of something like multiple wall-wart supplies, each providing the output needed for the separate functions. And attaching them to the circuitry where it normally exited the bridge rectifiers...eliminating the transformer and BRs...is this crazy? I’m assuming from your comments the negative voltages play a vital part, and they couldn’t be part of the wall-wart scenario?
That negative voltage and “driver” thing really throws me for a loop—I’ve never dealt with that in my piddling projects...

Thanks GPE...

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Here’s one view of the transformer...

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BillC...thanks again...
I went ahead and put the transformer back in place and soldered all connections. I then checked the outputs of the two bridge rectifiers. (Black probe on minus side, red on plus side—had to study up on that to be sure I was headed in right direction...remember, I’m a hacker/jackleg/fixer) and one showed around 9vdc, the other right at 28vdc. I’m thinking the 9v is a bit wonky but I kept moving...
On a whim, I plugged in the “dud” board I had received from Steve, and I got some playfield lights, and zeroes in the score display. Flippers worked, and the “bouncers” worked. Running finger through the rollovers some added score in display (with sounds) and some didn’t. The round targets sounded and scored. The 4 spinning gates—3 worked with sound and score, but 1 didn’t. In the middle of these tests I had pulled the board back out and resoldered about 7 spots that looked a little suspect. Reinstalled and seemed to do just a bit better...
I couldn’t find a 5 ohm resistor in my stash to replace my original board’s missing one, but found a 10ohm, 1 watt, and thought “what the heck”...within 2 seconds of powering up, I saw the familiar curl of smoke so that didn’t work...
Again, not skilled in how the circuitry works, I plugged in the board without the resistor and thought maybe I could check the values on the input and output of the 15v regulator, but got nothing—guess it needed something in that resistor spot?
I was looking at the back of the board to see how I thought the power flow ran and thought that the bad resistor is just before the input to the regulator, but before that are the two diodes—and it appears to my odd thinking that they are oriented so that current doesn’t flow through them to even get to the resistor? I’m sure I just simply don’t understand how they work...
On the dud board I measured those same points on the regulator—I believe it was about 35 or38 volts on the input, and about 15 volts on the output...so...(I’m scratching my head on all this even more now LOL)

Will send more pics shortly...orthopedic doc appt to get to for my broken big toe (dropped trailer gate on it!)

Only pics I have of the two bridge rectifiers mounted in the case with the transformer and what looks like a relay. No other boards in this machine...

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Thanks guys for more good tips...if you’ll pardon my ignorance, (I swear the older I get I forgetting basics!) when I measure those points you mention, WHERE is the black probe going? On the Bridges I finally was able to make out the plus and minus symbols on the schematic so that’s where the probes went. (At one point I had selected a position on my meter that was tripping one of the breakers when I tried to measure, but then another DC position worked fine ) On the diodes, “measure across”—that means one probe on one end, and the other on other end, right? And on a normal diode, if you’d then flip the probes and have one differing reading, then that would mean a bad diode, yes? And...the Zener thing....seems like I remember it acting differently from others—maybe conducts both ways?
I’ll get those measurements later tonight

Here’s what someone came up with on another electronics forum...

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GPE...
Probing those two diodes (probes at each end) bottom one is showing 1.5 dcvolts either way; top one is showing 2.5 either way...

BillC...
BR1 Orange/blue 12v...8vdc
BR2 Black/red 56v.......26vdc

BR1 Brown/green 9v.....8.7 to 8.8vac
BR2 White/white 30v....28.7vac

(The last number in each line is my measurement)
Also attached is a little better pic of BR2

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Overall pic of supply:

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I think I did see video last night on testing the BR...I’ll take a stab at that later this evening...
For the last little bit I tried some other measurements with the “dud” board installed...
Using the hand drawn diagram above I went from the 1N54001 (32.1 on left, 37.5 on right of it). At the top of the first zener, I got 37.7, 35.3 other end, 35.4 top of next one, 33.7 bottom of it. At the entry point of the 5.6 resistor 33.3, 33.7 at end of it. Into the 7815 with 33.4, out of it with 14.6....
Does that tell anything?

Can’t thank you guys enough for taking the time to try and explain so many things for me. It’s a wealth of information to a “jackleg” like me, and I’m trying to wrap my head around what I can. (I can surely see where a board schematic would be such a huge help as well)

Here in a little bit I’ll get all my magnifiers together and see if I can glean any more info on the diodes...

Also, on the question of input voltage measured on that 5400...I came up with about 33-35 volts but was in DC mode on my little meter...

Vpp or vrms? LOL I don’t have a clue, other than to say it’s a cheap meter—about a 20-30 buck model...

For ground, I was using the ground side of that wire-wound resistor...

All of my measurements have been from the “dud” mostly-functioning board—I was hoping that by getting various references around it, I could compare to the original board (the one that had the missing-smoked resistor in the first place.) I was hoping I could get it to at least stay “on” so that I could start comparing readings with the other one, by so far, the resistors I’ve put in have all smoked in about two seconds...

Also, I will order new Bridge Rectifiers...when I was measuring them earlier I had some trouble getting good connections on some to enable a reading...
Could a weak/no connection on them cause a few of the playfield things not to work? With the “dud” board I’m amazed at how much is working correctly (at least making sounds and adding to score)...I’m guessing maybe about 7 or so functions not working. For example:
Of the four spinning gates, 3 are fine—the 4th one on right side has nothing. The right side kicker sometimes tones, but doesn’t add any score—left side is fine. The rollover in the middle top alley doesn’t work. I think I’ve found so far that a couple I’ve looked at have power on one wire (about 9voltsDC) and when shorting the two pins together I get voltage on the 2nd pin but no actions...and jostling wires doesn’t seem to make any difference...
The saga continues LOL

Ok...those two zeners are indeed, 1N4733, as seen through about 3 pair of magnification...

I went back to measure the input side of that 1N54001 (this time on the AC setting) but I had another brain fart—where do I get the ground for the black probe?
I had it again on the negative side of that 1K 5w resistor and was getting a high number—I think I remember about 85 or so, and the output side (cathode) was about 60-something. This was with the game turned on, but not yet in a play mode (didn’t hit the credit button)...I turned away for a second, while I was still probing both sides of it, and suddenly the machine went into the play mode (as if I pushed the credit button)...scared the crap out of me! At that moment I probed both ends again, and now I was getting much lower numbers on each end of it (can’t recall at this moment exactly)...........duh! I think it just hit me that I needed to flip back over to the DC setting to get the reading on the Cathode side (?)

Digging a little farther, I traced where the signal came from that fed into that 54001...it appears to connect to a small jumper, then into a long trace that went to one of the two edge connectors. (Pin 9 on the 15pin) That appears to then feed through a wire to the harness that plugs into the supply box, and then looks like it originates at the Bridge Rectifier 2, 28vdc red wire output...

Incidentally, looking again at the original board at the two zeners, they sure look like they got hot and darker in color, compared to the crippled (dud) board...

Haha! Hey Ken...not just yet. I got the new rectifiers several days back but have been so busy doing DIY house projects for the lady...hope to get back to it within the next few days...(I have been able to keep searching/watching YouTube videos on pinball and that’s helped prepare me a bit more)

FINALLY...just last night managed to get the new Bridge Rectifiers installed...hoping to give it a try tonight, but still using the DUD board, since it seems to have more working on it than the original.

I did come up with one question though—I was following the power supply schematic in attaching the wires from the transformer to the rectifiers. The large YELLOW wire labeled as COM from the transformer—according to the schematic, I don’t see it. Unless it’s the one labeled as GREEN. According to my pics of the original wiring, the yellow is paired with the green to one rectifier terminal. I connected it that way...

Well...I’m worse off than before...hooked up to the machine; one playfield light came on at top alleys, flippers worked, but nothing else. No start. Back onto the bench trying to check voltages but brain fart has stopped me. I can’t seem to get any good measurements—I’m lost with my meter...can’t decide where to touch ground lead (this negative voltage thing has thrown me for a loop)...
I want to test the rectifier leads but not sure what’s correct positioning...??

I did more studying and next I’ll go back and recheck my wiring, then if all is well, I’ll check the BRs with meter (YouTube videos helped me figure out my brain fart)

Oops. Guess I must have been too tired before, but a recheck of everything and now all is well with the new BRs and voltages...now, back to checking the supposed “dud” board, and then hoping to find that issue with the original board...