Paragon - Power Fault ?

[DRD]

My paragon has been tombed for a few months. It was last used in league play back in the spring but began smelling "hot" after a couple of hours with a whiff of chip burn-out. A few of us looked over it, nothing appeared to have failed at the time, but we retired it as a precaution.

It is now up and running but showing problems.

I wonder whether all can be traced to a poor power supply ?

1. The gi dims a little when the flippers are hit
2. It can blow the dedicated flipper fuse on the solenoid board when you machine gun the flippers to test them
3. I get a rogue pop bumper firing from time to time. Every 30 seconds perhaps. No other solenoids display any issues . The does not register a score, so it is not a problem with the switch matrix. It pops when another solenoid is fired elsewhere in the game, various solenoids seem to trigger this erroneous firing
4. I get an erroneous tilt. Perhaps every 2 minutes. I have changed the tilt switch capacitor. It again seems to happen when a solenoid fires, various ones seem to trigger this

These faults occur with original and altek boards. I swapped in altek solenoid and mpu boards in an attempt to cure it. This did dramatically reduce the rogue tilt frequency - as it tilted all the time with the original boards, and sometimes would tilt immediately on power up with the original board.

The only other thing I can think of is that I get a very occasional flipper misfiring of the upper left flipper (perhaps fires twice), but this is doubtless a flipper switch / eos issue as these old games put the full 43v down these switch lines. I could not be bothered to fix it as it does not affect game play. This will be a case of switch pitting or a minor switch gap issue. But could cause arc-ing, power spikes etc as these old flippers do not have the spark suppression capacitors on them

Any ideas what may be wrong please ?

how do you test the adequacy of the piwer supply to cope with the load when solenoids fire ? Do you look for ac ripple ?

Thanks for any suggestions

 

[stoptap]

I'd definitely look for AC ripple.

 

[JMP]

http://www.pinballinfo.com/community/forums/technical-questions-help.14/

Wrong forum section David.

 

[DRD]

Thanks for the suggestions.

Well, the power seems OK. My crappy meter gave a steadier 5v dc than on my adjacent Centaur, a game I bought from some dodgy Geeza in Leeds. The ac ripple seemed identical, though I think my meter is a bit crap so I cannot read much into this. I have ordered a new Fluke meter to double check.

There is a lengthy thread on pinside about erroneous pop firing. As I am running new altek kit, I think I can eliminate much of what was discussed about old boards, failing capacitors, resistors etc .

In short, erroneous pop bumper firing seems to be a known issue with these 35 year old Bally SS games. The other fixes seem to focus on back emf, spark type, induced current, voltage leaking across old/ dirty wiring loom type scenarios ...

"In summary there are a lot of things that can be done but I would go down this list in order until good results are obtained:

- Un-weave the playfield harness up into the back box (Easy).
- Add 2-3 microFarad caps to the EOS switches (Easy)
- Add .1 microfarad caps to the flipper buttons (Easy)
- Run new flipper wiring from the back box to the flipper buttons, separated from the cabinet power and coin door harnesses. (Medium)
- Run new flipper power lines on the playfield outside of the original harnesses (Medium)
- Run new power lines to all the playfield coils (Hard) "

The full version is here ...

https://pinside.com/pinball/forum/topic/pop-bumper-fires-with-flipper-activity

 

[pinballmania]

Have you replaced the flipper diodes as I suggested?

 

[Nedreud]

Hey, @DRD, to be clear, you've swapped in ALLTEK boards for both the MPU and SOLENOID DRIVER/REGULATOR? Just checking because it's the solenoid/regulator board that handles all the clean-up of the power supply for the +5VDC to the digital electronics (MPU and SOUND) so assuming the ALLTEK is working then that should be ripple free.

The AS-2518-18 RECTIFIER BOARD (the one that's mounted on the chassis plate with the transformer) just converts 4 of the 5 transformer output voltages from AC to DC, and provides the front line row of fuses for each voltage.

As a basic test you can start by checking the output voltages from the transformer. This is only a guide as there can be some variance when not under load. Remove the fuses from the rectifier board and check you get roughly the following AC voltages across the pairs of "E" points:

E3-E4 49 VAC - Solenoid Bus (converted to 43 VDC then fed to the solenoids)
E5-E6 173 VAC - Display Power (converted to 230 VDC and regulated to 190 VDC by the AS-2518-22 SOLENOID DRIVER/REGULATOR)
E7-E8 7.3 VAC - General Illumination (this is fed directly to the lamps, no AC to DC conversion)
E9-E10 7.8 VAC - Switched Illumination (this is used to power lamps controlled by the AS-2518-23 LAMP DRIVER)
E11-E12 12 VAC - Digital Power (converted to 11.9 VDC then regulated to +5 VDC by the AS-2518-22 SOLENOID DRIVER/REGULATOR)

The E-122-125 transformer used on PARAGON is the weediest of all the transformers. If it's not kicking out these voltages maybe it's toast, especially if you can test the outputs of the AS-2518-18 and AS-2518-22 whilst in use and under load.

AC ripple is only important on the +5 VDC output from the AS-2518-22. It has to be a good quality 5V because it's used by the digital electronics on the MPU and SOUND boards. Too much ripple and it can affect logic switching, memory and CPU stability. And "too much ripple" means anything more than about 150 mV (millivolts) on the +5V. To test, connect your digital multi-meter to GND and TP5 on AS-2518-22 and set the range to cover 5V on DC. You want between 4.90 and 5.25 VDC. Then switch your multimeter to AC and check that there's no more than 150 mV.

There's oodles of ripple on the 43VDC for the solenoids because although it's rectified (the negative part of the AC cycles made positive) it's not smoothed. The 50 pulses per second is simply too fast and in the same direction to cause any "jitter" on a coil:



There could still be issues with the AS-2518-18 RECTIFIER BOARD. The original bridge rectifiers are notoriously underrated, and are now also very old. Upgrade them to something much chunkier and mount them on the topside with some heatsinks. There are also several improvements that can be made to the PCB and replacing the header pins never hurts either. I did this on my PARAGON: http://www.pinballinfo.com/communit...storation-1978-bally-paragon.6519/#post-39549

But do check your wiring. Whilst working on MMPM I've discovered all sorts of gremlins, such as opening and closing the backbox door blows the 1A under-playfield fuse for all the non-flipper solenoids! And whilst you're it if there are any IDC connectors replace them with proper Molex KK crimp/solder Trifurcons and then ceremoniously burn them.

 

[DRD]

Thanks fellas.

I have swapped out the main flipper coil and changed diodes on the right hand side (as my machine gunning blew the rhs fuse on the solenoid board). I will do the left next

I have got altek mpu and solenoid boards in at the moment. The 5v seems very stable and spot on.

I cleaned and adjusted all the flipper eos and cab switches as necessary. This seemed to help a bit actually with the bogus popper. I replaced quite a few of these high voltage switches last year with new parts, but they were still filthy.

In terms of tranny output .... I can't see all the E things @Nedreud . Do I need to remove the board to get underneath it ?

Using the TPs and suggested voltage data from http://techniek.flipperwinkel.nl/ballyss/rep/index1.htm

Bally Tranny board (suggested reading) / actual reading

Tp1 (5.4) 5.8
Tp2 (230) 239
Tp3 (11.9) 17.4
Tp4 (7.3 AC) 6.6 AC
Tp5 (43) 48.2

ALTEK Solenoid Board (suggested reading)/ actual reading

Tp1 (240) 263
Tp2 (190) 185
Tp3 ?....
Tp4 (12 unreg) 17.38
Tp6 (5) 5.00
Tp7 (43) 49