Quoted from MiloBloom:
Hello everyone - my Hook machine plays fine but has no sound at all anymore. It used to cut in and out, and seemed to "reset" itself at the end of a ball, but now it's completely silent. If I try to adjust the volume I get brief static through the speakers but that's it.
I am interested in a new Pinsound board anyway, but I'm wondering if that would solve the problem on its own or if there's anything else I need to check first.
Thanks in advance.
from flipperwinkel, might be helpful, but one of the more experienced pinsiders could point you in the right direction I am sure
(I printed out all 3 parts of this and have found it handy a few times )
http://techniek.flipperwinkel.nl/desega/index1.htm
3n. When things don't work: Sound Problems
Loud Hum from the Speakers.
The sound works, but there is a very noticible loud hum coming from the speakers. This is often a ground problem. It could be as simple as tightening the screws that secure all the printed circuit boards to the backbox. Also it could mean the large filter capacitor (usually 1000 mfd at 16 volts) on the sound board needs to be replaced. Look for a large capacitor that connects +5 volts to ground.
No Sound at All - Sound Board Voltages.
The sound board needs +5 volts, -5 volts, +12 volts, and -12 volts to operate. These voltages come from the power supply board except for -5 volts, which is created by the sound board itself. After the -12 volts gets to the sound board, it is regulated down to -5 volts using a 7905C voltage regulator at VR1. If the voltage regulator VR1 fails, this could pass -12 volts directly to chips which are expecting -5 volts, thus destroying them. This is a fairly common problem, and will disable the sound board completely. On games Batman to Batman Forever, the -5 volts goes to chips U30 and U28 (LM833). On games Laser War to Turtles (sound board 520-5002-0x), the -5 volts goes to chips 5B (4052), 3B, 6B, 7B (all MC3403).
Check for sound board voltages at the input connector to the sound board. This would be the +5, +12, and -12 volts at connector CN2 (or CN4 on sound board 520-5002-0x used on Laser War to Turtles):
◾CNx pin 1 = +5 volts
◾CNx pin 2 = Ground
◾CNx pin 3 = -12 volts
◾CNx pin 4 = NC (no connection)
◾CNx pin 5 = KEY
◾CNx pin 6 = +12 volts
Next check for -5 volts at the capacitor C49. Use a DMM, and put the red lead on the leg of this capacitor which connects to VR1. Put the black lead on the other leg of the capacitor (ground). The DMM should show -5 volts. This applies to all revisions of DataEast/Sega sound boards as used from Laser War to Batman Forever.
On games Batman to Batman Forever (all sound boards but 520-5002-0x), this procedure should be repeated for the +5 volts. This voltage is received directly from the power supply, but it is also produced from the input +12 volts through voltage regulator VR2 (7805C) on the sound board. Check for +5 volts at .1 mfd capacitor C47. Use a DMM, and put the red lead on the leg of C47 which connects to VR2. Put the black lead on the other leg (ground). The DMM should show +5 volts. This applies to all revisions of DataEast/Sega sound boards as used from Batman to Batman Forever.
No Sound at All - PAL Chips.
DataEast/Sega sound boards use specialized PAL program chips at U19 and U20 (PAL16L8). If there is no sound, and all the sound voltages are present (+5, -5, +12, -12 volts), suspect these two PAL chips next. These are custom programmed chips. They can be ordered from Stern, or custom programmed (email Jerry Claus for a quote).
Sound Problems on Checkpoint and Turtles.
Some Checkpoint and Turtles games had their sound boards mis-wired to the speakers. Make sure the game is wired like this:
◾Right Speaker +: Black-Yellow
◾Right Speaker -: Black
◾Left Speaker +: Red-Black
◾Left Speaker -: Red-White
◾Center Speaker +: Yellow-Black
◾Center Speaker -: Yellow-White
◾+ Speaker Terminal: Left lug
◾- Speaker Terminal: Right lug
Speaker polarity is determined by looking at the back of the speaker, with the lugs pointing towards the ceiling. This problem was discussed in service bulletin number 29.