My Volcano project is completed except for some sound issues. The pin has a rottendog MPU, NiWumpf driver board, and swemmer sound board. I have repined all the connections and purchased a new repinned harness for the mpu/driver board connection.

The first issue is that I have to maneuver the A3J5 connection on the driver board board to accomplish any sound in game. There appears to a sweet spot on the connection that works but if fully attached/seated to the driver board there is no sound.

I am also only hearing the voice sounds "volcano" and "tilt". "Tilt" - tilt, tilt, tilt - occurs at the start of multiball instead of the eruption.

Any advice would be appreciated.

Chris,

Thanks for the help.

I did repin A3J5 and the sound board connector and double checked to make sure the pins are in the right locations.

If I ground the connecting pins at pin1 1, 5, 6, and 7 at A3J5 connector I get the correct sounds. If I reconnect A3J5 and ground z13 pins 2, 4, 6, 8 I don't get any sounds. It is a new Niwumpf board so I doubt z13 is bad. I think I read somewhere that using a logic probe all sound lines off z13 must read high. All read high except for pin 8 which is low. EDIT. Had an extra sn7404n and time so replaced z13. No change.

S16 - which I am guessing is used in Volcano produces no sound when I ground the solid green connection at connector 9.

One odd thing - I have noticed that if I start a game I get the attract mode sounds every so often like the game is actually in attract mode.

Yes. Sound board tests correctly when in diagnostic following flow chart in manual.

One other odd thing. I replaced z13 on driver board - had a spare 7404. No change in sound. However if I connect five volts to pin 9 which should be the input for I think sound 8 I get a high pitched tone that stays on even when voltage is removed. Touching other input pins with 5 volts on z13 results in no sounds. Damn thing is driving me nuts.

Chris,

Not sure I am following. are you saying that perhaps z13 has a ground short somewhere? I thought sending 5 volts to each of the sound input pins on z13 should result in a sound being heard.

Yes, thanks. Very helpful

I went back into sound board test diagnostics. Flow chart diagnostic checks out fine. When I ground a6j1 connections 8,9,10,11,12 the correct response is given.

However if I ground z13 pins 2,4,6, 8 I get “FAILS” so it would seem the connections off the driver board to the sound board are good.

This a new sn7404n chip but I think the logic probe readings are off.

In attract mode and in game I get the following readings. shouldn't the inputs be hi and the outputs lo?

pin 1 lo - pin 2 hi
pin 3 lo - pin 4 hi
pin 5 lo - pin 6 hi
pin 9 dead - pin 8 lo

Going upstream I get the following off the MPU ICs at z31 and z27 in attract mode

z31
pin 2 dead - pin 3 dead
pin 5 dead - pin 6 dead
pin 9 lo - pin 8 lo
pin 12 lo - pin 11 lo

z27
pin 2 lo
pin 4 dead
pin 6 dead
pin 12 lo

Bumping this last post. Can someone confirm what the readings should be on the driver board and MPU chips. I have replaced z13 but not z31 and z27 on the MPU.

Thanks,