Any Bally experts out there? I have some voltage questions 1978 Playboy

[poppo]

The little c29 cap is clearly shot on the driver board.  What are the odds that the VR has lived?  Do you figure my new C23 is shot from the AC as well?  I am wondering if I need the entire 5V kit or run to the shack tomorrow for the small caps.  What do you think?  I have changed to the #47 bulbs.  I would like LED but will have to wait and see what I have in this thing once it is going.

Well, if you fed 7.3VAC into the output of the 5VDC regulator, chances are pretty good that it's toast too. The bad news is that you may have cooked a lot of other componets too.  You basically fed 7.3VAC into every 5VDC IC chip.  

[jbshocks]

I fed AC to TP5 since it was soldered to the board.  All connectors were pulled from the board.  So you think more than the 5 volt kit? 

[poppo]

I fed AC to TP5 since it was soldered to the board.  All connectors were pulled from the board.  So you think more than the 5 volt kit?  

Well, if no other boards were plugged in (i.e. the MPU, lamp driver, etc.), then you should be ok. But if anything that runs off of 5VDC was plugged in, then it may be toast. The board that has the 5VDC regulator feeds all of the other boards directly. So unless they were all unplugged in the top box......

I would get the whole kit.

[Mr. Dinoman]

You beat me to it...If you swapped #8 and #10-Normally pin 10 is 119vac to the reg. board and #8 is the 7.5vac to the GI's...You should have seen a brigth flash and ALL the GI's would have burned out...

[jbshocks]

I was following a start up guide that had voltage checks along the way so I never got further than plugging J3 into the driver board.  I will get the 5volt kit and see where I land.  Thanks

[poppo]

You beat me to it...If you swapped #8 and #10-Normally pin 10 is 119vac to the reg. board and #8 is the 7.5vac to the GI's...You should have seen a brigth flash and ALL the GI's would have burned out...

Are you looking at the right schematic? Pin 10 (of J3) is the 7.3VAC GI line. Pin 8 is the input to the 5V regulator. Swapping them put 7.3VAC into the regulator instead of rectified AC.

jbshocks,
You "shoulld" be ok with the kit. It was not the output of the regulator as I first feared. But you did feed raw AC into the regulator which I'm sure cooked it, and also killed the capacitor (that does not like AC).  

If you order that kit from that link, you may want to order some other things, like some of the lamp driver SCRs (both types). They tend to go bad.

[channelmaniac]

The little c29 cap is clearly shot on the driver board.  What are the odds that the VR has lived?  Do you figure my new C23 is shot from the AC as well?  I am wondering if I need the entire 5V kit or run to the shack tomorrow for the small caps.  What do you think?  I have changed to the #47 bulbs.  I would like LED but will have to wait and see what I have in this thing once it is going.

If AC has run through an electrolyic cap, check it with an ESR meter. If bad, replace. If you don't have an ESR meter then just replace it. Standard capacitance tests on a multimeter will NOT show damage to a cap.

[poppo]

Since the one cap is definitely toasted, I would just replace them both (along with the regulator).

[Mr. Dinoman]

Answer to your ?....The schematic for the Power transformer module that feeds everything....J3 Playboy 1978...JB stated Powersupply earlier

[poppo]

Answer to your ?....The schematic for the Power transformer module that feeds everything....J3 Playboy 1978...JB stated Powersupply earlier

Normally pin 10 is 119vac to the reg. board and #8 is the 7.5vac to the GI's...You should have seen a brigth flash and ALL the GI's would have burned out...

Better check again.  J3 P10 is 7.3VAC GI lighting.  J3 P8 is 11.9VDC (not 119VAC) that goes to the 5VDC regulator.  

In any case, he has the wires back where they belong, and now just needs to get the +5VDC back up.

[Mr. Dinoman]

Could be...I have a bad photo copy...

[jbshocks]

Parts finally arrived from Big Daddy today and I changed the entire 5 V VR kit and all voltages checked out.  I hooked up the rest of the machine and plugged it in.  The flippers kicked which startled me and I unplugged it.  I plugged it back in and the displays all had a little glow but no numbers.  I see no kind of flickering at all on the MPU LED to indicate a boot is going on.  While looking it over I smelled smoke and realized it was under the play table so I unplug and take a look.  It was the solenoid that knocks the outside of the machine.  I probably have a bad transistor and coil at this point but I cut the wire off the cable in hopes of dealing with the boot problem. 

I check the voltages on the MPU at TP1, 2, 3 and 5 and all in spec.  This MPU did have corrosion but not really that bad.  I bought a corrosion kit for it but only changed one transistor that had a broken leg at Q2.  Should I shot gun the rest of the kit in?  Change the U8 socket and U8 and retest?  What is the next best move? 

[poppo]

This MPU did have corrosion but not really that bad.  I bought a corrosion kit for it but only changed one transistor that had a broken leg at Q2.  Should I shot gun the rest of the kit in?  Change the U8 socket and U8 and retest?  What is the next best move? 

If Q2 or associated parts are bad, the LED won't do anything. You can ground TP6 to see if the LED is working.

The corrosion may not look bad, but if it get's under the chips and sockets it will cause all sorts of problems.

There used to be some good step by step troubleshooting info here, but it looks like most of the links are dead.
http://www.pinrepair.com/bally/

I have to look, but I think I may have a working MPU somewhere if you can't get yours running.  
Just checked. I don't have it any more.

[jbshocks]

I have been using that pinrepair guide all along and it has been dead the last 2 days.  I have pulled up some cached copies to work from.  I used a pc power supply to do testing which makes things go a ton faster.  I changed out the LED and now I have a solid light.  I tried shorting pin 39 and 40 of u9 to get it to boot and nothing.  I have now changed U8 and its socket though now that I have read more it would have nothing to do with a solid light.  From the corrosion kit I have replaced all 3 transistors, all 3 diodes and all of the capacitors.  I did not change the resistors as they look good and seem to check fine.  I am just about to throw in the towel on this MPU,  after all I don't know if someone plugged the machine in with with the corroded MPU and fried the chips.  I wish I had a logic probe to watch pin 40 U9 to see if the reset circuit is working. 

[poppo]

Depending on how much you want to spend on trying to fix yours, you might be best off buying a Ultimate MPU or a Dash-35. Even the used original MPUs seem to have gone up quite a bit on ebay.  Every used MPU I had bought always ended up having some sort of intermittent problem. I finally bit the bullet and bought a Dash-35. Never had a problem since.

To troubleshoot these boards, you really need a logic probe or a scope.

If you have a eprom burner, this may help.

http://home.scarlet.be/~fb054529/bally/ebally.htm

It's test ROM that aids troubleshoooting.

[jbshocks]

Thanks for all the help on this.  should I be able to read the 7825 prom chips in my eprom burner?  I am wondering if by chance I have bad cpu, ram or roms but can't decide if I want to throw $30 more at this thing just to end up buying a new board.

 Also,

Any Idea what the displays should be doing with a locked up MPU?  Mine have a glow to them but no numbers lit up.  I would assume this would be correct with a locked up game.  I am hoping I don't move from bad MPU to bad displays.

[poppo]

I'm 99.999% sure the displays won't do anything if the MPU is locked up.

As for the ROMS, it might be a good idea to jumper the MPU for 2732 chips if it isn't already.
Here are the ROM checksums if you can read them in your burner.
http://pin-logic.com/early_bally_pinball_game_roms.htm

Does the green LED even flicker at all on power up?

[jbshocks]

Do you know what is needed to merge the U1 and U2 chips together?  I have not seen a combo U2 rom for playboy.  Also do you know what U7 does?  Would it need to be replaced?  I don't see U7 rom files.

Never a flicker just a short delay before the LED lights

[poppo]

Do you know what is needed to merge the U1 and U2 chips together?  I have not seen a combo U2 rom for playboy.  Also do you know what U7 does?  Would it need to be replaced?  I don't see U7 rom files.

Use this command based on the names of the files on ipdb.org to merge U1 and U2. Easiest to put it in a batch file and put in the same directory as the two original files. 2732_U1_U2.bin  would be the merged file. The merged ROM goes in the U2 socket

copy /b 743-14_1.716 + 743-12_2.716 2732_U1_U2.bin /b

I belive U6 can just be burned right to a 2732 using no offset, but using this command will work too which just puts a copy in each "bank". 2732_U6.bin is the resulting file.

copy /b 720-30_6.716 + 720-30_6.716 2732_U6.bin /b

U7 is the static RAM chip. It "can" go bad. But you would need to get some LED flashes before it's tested.

If you need to locate that test ROM, send me an e-mail.

[jbshocks]

does it matter what 2732 chips I get?  Does prefix and suffix matter?  I put the stock chips on my burner and they all show blank so either dead or my reader will not read them.

[poppo]

does it matter what 2732 chips I get?  Does prefix and suffix matter?  I put the stock chips on my burner and they all show blank so either dead or my reader will not read them.

Any 2732 chips should work fine as long as your burner will work with them. I know for sure that 200ms (2732-200) will work.

If they are stock ROMS, are you using the 2716 setting? I don't recall if I had problems reading stock chips or not.

Also 

[jbshocks]

they are actually 7848 chips but those are not in my list.  I just tried the 2716 and nothing.

[jbshocks]

I am just about to throw in the towel and order a board.   I think I will sleep on it.  I burned the test eprom and re did the jumpers same behavior.  So according to instructions it says to try to jump 5v to pin 40 I do that and light goes out  but does not cycle.  The socket then starts to melt at pin 40.  I bent pin 40 up and decided to give it 5v directly and take the board out of the middle and it would just dim the LED.

[poppo]

The socket then starts to melt at pin 40.

Hmmm.... That's not good. Did you pull all of the chips the directions tell you to? There is no way that you should have a meltdown on pin 40. But the reset line does go to other places, so there could be a short somewhere.

I agree that it might be time for another MPU and use this one for spare parts.

[jbshocks]

I did pull all other chips.  just the 2 in it.  one of the clock signals show 3.88v which is high as well so I am wondering if this got plugged in with all the corrosion and burned a bunch of the ICs.  That may also explain why the led was burned out.