Need help with Sinistar (Chicago area)

mjenison

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Need help with Sinistar

Hi all,

After rebuilding my power supply for my Sinistar, the sounds are goofed up now. Fire is replaced with a different sound, game is constantly repeating "Beware, I live", game start sound replaced with "Run, Coward". Explosions are correct though. Connections and voltages seem ok.

Any other advice on what to check is appreciated as well.
 
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Ok, I found a post that states I should get sounds when I disconnect the harness going from the rom board to the soundboard, and ground the pins for that connector:

pin 2 - Rawr!
pin 3 - alert sound
pin 4 - explosion
pin 7 - some sound

I believe these match the tests during test mode:
sound line 1 - alert sound
sound line 2 - rawr
sound line 4 - explosion
sound line 5 - some sound

I don't know what "some sound" is, because on my game I get silence. Grounding pin 7 on the sound board gives me silence as well.

Hopefully this gives someone out there a clue as to how this issue can be resolved.
 
If you have a logic probe check
IC5 pin 2 = line 1
IC5 pin 4 = line 2
IC5 pin 12 = line 3
IC5 pin 10 = line 4
IC7 pin 6 + pin 4 = line 5
IC5 pin 15 = line 6
IC5 pin 6 = line 7 (sound data available)

Based on your symptoms I would check IC7 which is a 4069 hex inverter and make sure the signal from pin J3-6 is correctly being inverted at pin 6 and then re-inverted at pin 4.

ken
 
I see IC7 pin 4 pulsing during the line 5 loop test, as well as IC6 pin 13 and IC5 pin 15, so looks like all inputs up until IC10 are correct. I swapped in a Joust sound board temporarily, swapping in the Sinistar ROM and it worked, so ROM and 6808 are known good, and the problem is localized to the sound board.

Joust board revealed the missing sound to be the crystal capture sound.
 
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It may be the aptly named PIA (6821) chip then. Check to make sure all of the lines are pulsing on on the appropriate PIA leg (sorry I don't have the schematics handy right at the moment). If the pulses are getting to the PIA but not appearing as sounds, then the PIA needs to be replaced.

ken
 
Yeah, all the signals are getting to the PIA as expected, so I suspect this chip may be the problem. Other sounds are appearing in the place of correct sounds, so it's almost like some sort of addressing device has gone bonkers.

Things I learned while working on this:
1) My Joust sound board doesn't have the connector for the additional speech board that Sinistar has; it could be populated I suppose to allow it to be converted to a true Sinistar speech board
2) The difference between Joust and Sinistar speech boards is jumper W1. W1 is a control to say whether to mix speech audio and soundboard audio. If you don't have W1 populated, you need to have the speech board connected to hear sound. If you have W1 populated, you don't need the speech board connected to hear sound.

Also, can someone confirm the dip settings on the Sinistar soundboard? I believe the correct settings is for both dips to be set to off.
 
what does it mean in the case of Sinistar by way of the extra speech board?

There are two boards for sound in a Sinistar, the sound board and the speech board. The speech board is about 1/3 the width of the sound board and contains all of the speech ROMs.
 
The correct setting is to have both switches set to 'on'. See note 5 (that is a schematic error joke :D).

ken
 
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