I have a Royal Flush Deluxe that played fine until recently. The game started flaking out after a few minutes of play. Lights would blink and solenoids would fire randomly and the game would end. Then the fuse for the target reset blew.

I found a diagram for the power supply and measured each test point...

TP1 measured 63.6V vs 60V expected.
TP2 measured 44.8V vs 42V expected.
TP4 measured 5.2V vs 5V expected.
TP5 measured 11.6V vs 8V expected.

The game did have the big orange capacitor replaced, but none of the ground mods done. I don't have a wiring schematic and trying to decide where to go from here. Is the 11.6V reading a problem at TP5? Should I replace the power supply? Any advice is appreciated. Thanks.

#2 6 years ago

INK

Inkochnito

Pinside member

Piershil

12y 91,650 3,167 12

Start with reading the Pinwiki on the ground mods....
http://www.pinwiki.com/wiki/index.php?title=Gottlieb_System_80
Check connectors ect.....

PM coming....

#3 6 years ago

GPE

G-P-E

GPE

Omaha, NE

13y 76,800 2,778 4

TP5 at about 12V -- CR7 is bad (open).
System 80s used a 30 ohm resistor for R10 and a high wattage 8.2V zener for CR7.
A 30 ohm resistor means there is about 140mA going through R10 and CR7.
R10 would be dissipating about 0.6W and CR7 would be dissipating about 1.15W.

There is absolutely NO need for this circuit to be dissipating this much current considering the 8V tap is drawing nearly zilch for current. Replace R10 with a 470 ohm, 1/2W resistor and replace CR7 with a 1N4738. This will get your 8 volts back and these components on your board will run far cooler.

#4 6 years ago

???

pmdub

Inactive member

Downingtown, PA

7y 17,550 49

Thanks for the help guys. I just ordered the resisitor and zener diode on ebay. When they come in I'll replace them and perform the ground mods as a start and see what happens.

3 weeks later

#5 6 years ago

???

pmdub

Inactive member

Downingtown, PA

7y 17,550 49

I completed the suggested cr7 and r10 replacement and TP5 is 8.2V now. But, TP4 dropped to 4.0V and the game just wigs out when I turn it on. Solenoids firing and display flicking on and off. How important is TP4 dropping to 4.0V, is that related possibly?

#6 6 years ago

BIF

CactusJack

Pinside member

Lake Forest, CA

10y 80,050 4,200 93

If TP4 is the regulated 5v (as you originally found), then yes, 4 volts is a major issue. While ICs are usually rated for operation at 4.75 to 5.25, most MPU designs require 5.0 to 5.15 to be reliable.

Did you have to unsolder the large TO-3 pass transistor to replace the other components? If so, either the barrels for the 2 leads or the ones for the mounting screws are probably no longer soldered to the traces on the underside if the board.

#7 6 years ago

RAS

Raff

Pinside member

North Adelaide

9y 66,550 1,496 19 7

when you put q3 back on make sure its not shorting to the back plate check it with a multi meter , and test q3 make sure its not faulty , check for crackes solder on the header pins and the connectors, check the reset board that will give you problems just unplug it , check the 12v br too , and last of all you have to do the ground mods for all the boards adding new grounding wires to all boards ,and do the ground mod on the connector between the driver board and mpu board adding a extra ground wire on that connector, once you iron out these problems your machine will work like gold .

#8 6 years ago

???

Biffbar

Pinside member

6y 42,050 271

OP
Quoted from pmdub:
I completed the suggested cr7 and r10 replacement and TP5 is 8.2V now. But, TP4 dropped to 4.0V and the game just wigs out when I turn it on. Solenoids firing and display flicking on and off. How important is TP4 dropping to 4.0V, is that related possibly?

Use the trimmer on the power supply to adjust the 5V supply to about 5.1 volts (no more) at the test point. Best to disconnect the power supply outputs, to protect the other boards, until all the voltages are correct. Later on you will want to check the 5V reading at the cpu board, aiming for 5.<something> to 5.1 volts.
EDIT: Done several of these PSU's this year, and almost all had cracked solder and loose header pins. Good idea to reflow the pins when you have the cold plate off, (optionally do a variation of the PSU ground mod, tying the PSU ground to one of the threaded screw mounts, and removing coating at several spots on the cold plate).

#9 6 years ago

???

pmdub

Inactive member

Downingtown, PA

7y 17,550 49

Thanks CactusJack, Raff and Biffbar! I ended up unsoldering Q3 again so I could inspect the underside of the board. I reflowed a lot of pins and made sure nothing was shorting when I put it back together. This time TP4 read 5V and eventually got up to 5.2V after warming up. (Is this normal to climb a bit after warming?) Everything seems to be working well now. I'm back in business! BTW, Royal Flush Deluxe is a really fun game, maybe underated because of the sometimes annoying music, but that can be turned down or off.

#10 6 years ago

RAS

Raff

Pinside member

North Adelaide

9y 66,550 1,496 19 7

sounds like your back in business good luck

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