Joust sound missing

whoosh

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Hi. My Joust has no sound except it makes a repeating "laser gun" type of sound when the test button on the sound board is pressed. All of the wiring and voltages are correct. I have a few specific questions if anyone can help. Thank you in advance.

1. Should pin 40 of IC9 (6808) on the sound board go low when the reset button on the CPU board is pressed?

2. I know that each of the sound select inputs should make sound when grounded, but these do not.

3. Only pins 2 and 3 (wires 1 and 2) of the sound select inputs are pulsing and pin 6 (wire 5) is permanently grounded. Shouldn't they all be pulsing?

4. I'm not sure if the PIA on the ROM board is working, but I don't know how to check it and I don't want to replace it and risk ruining the board because my soldering skills are not that great.

5. With the game turned off, can resistor packs (DIPS and SIPS) be tested in circuit? To test these, does one lead of an ohm meter go on the common pin and the other lead on each of the other pins? The reason I ask is because this is how checked the resistor packs on the ROM board and sound board. They are rated at 4.7K ohms, but all of the pins read about 1 ohm except for pin 6 of the DIP on the ROM board which read .365 ohm.

Thank you,
Roger
 
I'd start with reflowing the solder on the ribbon cable to the sound board. Probably better to replace it entirely, but that can be a bit tricky if you don't have a good desoldering solution.
 
remove rom board and sound board. keep green harness connected to both. measure continuity between both sides. chances are the harness is good.

the PIA commonly fails on these.
 
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