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New to Pinball Info and looking for direction.

Up until those last two measurements I thought that your 170V supply was basically working, but now it looks like the transistors have been blown and we are just seeing enough current leakage with no load to develop voltage across the zener diodes. I think we need to measure it with some load on it.

With the power off unplug the bottom section of the CN6 connector on the sound card (it goes on pins 1 to 4). This will remove all power from the sound board as that may have been damaged by the original problem. Reconnect CN5, making sure the alignment is right then power up and immediately measure the voltage between the screw head and pin 8 of CN5 again and see what it is. If more than 170V then switch off immediately, otherwise you can recheck the other voltages on CN5 like you did earlier to make sure they are still in the range I specified and see whether you have any displays and whether any of the game works before turning off and reporting back.
What colour wire should be going to pin8?
 
From the meter it is the red wire. If you mean the wires in CN5 then looking at the earlier photo the wire in your CN5 that goes to pin 8 is a sort of orangey brown in the photo
 
From the meter it is the red wire. If you mean the wires in CN5 then looking at the earlier photo the wire in your CN5 that goes to pin 8 is a sort of orangey brown in the photo
I think it reads 333v. I panicked and switched the pin off without having a second glance. Could that be correct?
 
Up until those last two measurements I thought that your 170V supply was basically working, but now it looks like the transistors have been blown and we are just seeing enough current leakage with no load to develop voltage across the zener diodes. I think we need to measure it with some load on it.

With the power off unplug the bottom section of the CN6 connector on the sound card (it goes on pins 1 to 4). This will remove all power from the sound board as that may have been damaged by the original problem. Reconnect CN5, making sure the alignment is right then power up and immediately measure the voltage between the screw head and pin 8 of CN5 again and see what it is. If more than 170V then switch off immediately, otherwise you can recheck the other voltages on CN5 like you did earlier to make sure they are still in the range I specified and see whether you have any displays and whether any of the game works before turning off and reporting back.
Srry Keith. It was 65vac. I checked it again.
 
You need to be measuring DC voltage on pin 8 of CN5 not AC. All the CN5 measurements should be done on the DC ranges with the black probe on the screw head
 
OK, well that wont do any harm, but does confirm that the 170V supply is damaged. Now measure the other voltages on CN5:

look for the following voltages on the pins of CN5 with the negative lead of the meter connected to ground (e.g. push the probe into one of the screw heads in the bottom corner of the power board):
Note that Pin1 is at the bottom of CN5:
Pin 1 around 40v DC (not critical)
Pin2 Zero
Pin3 Zero
Pin4 +5.6V DC (should be within 5.4 to 5.7V)
Pin5 +5.6V DC (should be within 5.4 to 5.7V)
Pin6 Zero
Pin7 Zero
Pin8 +170V DC (should be between 160Vmin and 175Vmax)
Pin9 Zero
Pin10 Minus 5V DC (should be between -4.8V and -5.2V DC)
Pin11 +5.6V DC (should be within 5.4 to 5.7V)
Pin12 +12V DC (should be within 11V to 13V)
 
There wont be yet. I need to know the results of those other voltage measurements on CN5 before we go any further
 
OK, well that wont do any harm, but does confirm that the 170V supply is damaged. Now measure the other voltages on CN5:

look for the following voltages on the pins of CN5 with the negative lead of the meter connected to ground (e.g. push the probe into one of the screw heads in the bottom corner of the power board):
Note that Pin1 is at the bottom of CN5:
Pin 1 around 40v DC (not critical)
Pin2 Zero
Pin3 Zero
Pin4 +5.6V DC (should be within 5.4 to 5.7V)
Pin5 +5.6V DC (should be within 5.4 to 5.7V)
Pin6 Zero
Pin7 Zero
Pin8 +170V DC (should be between 160Vmin and 175Vmax)
Pin9 Zero
Pin10 Minus 5V DC (should be between -4.8V and -5.2V DC)
Pin11 +5.6V DC (should be within 5.4 to 5.7V)
Pin12 +12V DC (should be within 11V to 13V)
Everything is right except pin 8 which is reading 53vdc. 4 is reading 5.63 and 5 is reading 5. 62. pin 1 is reading 37.4. 10 is reading minus 4.2. 11 is 5.5 and 12 is 11. Pin 8 reads 150v when connector is unplugged.
 
OK although the -5V on pin 10 is out of spec at -4.2V.

You should have working general illumination lamps and a Game Over light now.

If you put some credits on the game by operating the microswitches on the coin slots a few times can you then start a game? You still wont have any displays or sound at this point, but we want to establish if the CPU and interface boards are functioning.
 
OK although the -5V on pin 10 is out of spec at -4.2V.

You should have working general illumination lamps and a Game Over light now.

If you put some credits on the game by operating the microswitches on the coin slots a few times can you then start a game? You still wont have any displays or sound at this point, but we want to establish if the CPU and interface boards are functioning.
GI and flashing lamps function and the game resets the drop targets and fires out a ball but no sound or display
 
That's very good. Power down and reconnect the bottom part of CN6 on the sound card and see if you then get any sound when you power up and try another game.
 
It's very likely given the voltages that were applied to the sound card when CN5 was offset. I just wanted to confirm.
 
Great, that saves a lot of work and expense. Based on all of the testing so far then there are four components that need to be replaced on the power board to get you back to a working machine:
TR1 - 2N3584
TR2 and TR3 - 2N3440
RG2 - 79M05 (-5V regulator)
 
It's very likely given the voltages that were applied to the sound card when CN5 was offset. I just wanted to confirm.
Keith the game fires up and resets the targets and pops out a ball. there are no displays and the pop bumpers don't fire and when the ball drains it does not send out ball 2. the drop tarets when hit drop but dont reset when all down (this may be normal as I have never had a pin with drop targets before) the award lights dont advance.
 
Great, that saves a lot of work and expense. Based on all of the testing so far then there are four components that need to be replaced on the power board to get you back to a working machine:
TR1 - 2N3584
TR2 and TR3 - 2N3440
RG2 - 79M05 (-5V regulator)
Okay great. I will order them up and do the necessary to replace the old ones. Thanks for everything today. I will let yu know what happens later on. Take care friend.
 
TR1 is on the heatsink at the top right of the board and TR2 and 3 are below that. TR3 usually has a small heatsink fitted on it which can be removed by spreading the gap in it with a screwdriver whilst lifting it off to fit onto the new one. RG2 is bolted to the board below F1.
 
From your last post it would appear that there are some other issues but they will be easier to fault find once we have the displays working again.
 
Drop targets should pop back up when all in the row go down or when a new game starts. There is a button inside the coin door to add credits if you need to.
 
Check what is fitted for TR1 at the moment as the 2N3584 is not very easy to find and it may already have been replaced by something in a flat plastic package such as a TIP49
 
Based on the other issue you reported with the game it is worth double checking that CN10 and CN11 on the CPU board also have their connectors correctly aligned with the pins on the board and no bent pins as all of those issues could relate to switch detection problems
 
Yes TIP49 would make sense and that is a good choice to replace it with (and a lot cheaper than any 2N3584 you will find). It should be fitted with a smear of heat conducting grease.
 
Great, that saves a lot of work and expense. Based on all of the testing so far then there are four components that need to be replaced on the power board to get you back to a working machine:
TR1 - 2N3584
TR2 and TR3 - 2N3440
RG2 - 79M05 (-5V regulator)
Apart from the TIP49 I have ordered the same part numbers as above. Will let you know when they are on the board.
 
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