Mr. Do! Sound Problem

[kjbleu]

My Mr. Do! sound isn't working right. I am getting one channel of sound it seems. If I get close to the speaker I can hear the other part of the music very faintly, and sometimes it comes on at for a moment here and there. I have the Mr. Do! with a separate sound amplifier, it's not on the pcb. Any suggestions?

 

[Phetishboy]

Check that mini amp pcb and fiddle with the volume control. You could have a loose connection on one of the speakers as well, either where they are soldered on to the pads or where the molex connection is (should be a four position female connection soldered to the amp). I have yet to splice mine into the wiring scheme, so at present I have no sound. So it could be worse.

 

[Bug59]

also possible is the volume pot might need a zap of contact cleaner,and then turn the knob back and forth to work in the cleaner a few times,(think of your ancient TV's and stereos,that had rotary knobs,that had crackly sound)...at least your's works,mine is completely dead

 

[mspaeth]

My Mr. Do! sound isn't working right. I am getting one channel of sound it seems. If I get close to the speaker I can hear the other part of the music very faintly, and sometimes it comes on at for a moment here and there. I have the Mr. Do! with a separate sound amplifier, it's not on the pcb. Any suggestions?

Probably a bad 76489... pretty common problem

 

[Gremlin75]

I realize I'm resurrecting a really old post, but I'm having the same problem.

The question I have for the group is: my H1 & J1 chips are labeled as TI J214X2 U8106 (see pic) - but I can't find anything on these chips online. Can I use a standard 76489 as a replacement? There's a few of those on eBay that I could pick up if so. Thanks in advance for assistance!

 

[SamWhiskey]

76489 is the correct part.

Are you sure, the chip is dead?
Had a board with strange sound, where one of the bipolar caps was dead.

 

[Gremlin75]

76489 is the correct part.

Are you sure, the chip is dead?
Had a board with strange sound, where one of the bipolar caps was dead.

View attachment 576558

I'm not. Probably should just replace both caps to be safe. Thanks for confirming the IC!

 

[Gremlin75]

76489 is the correct part.

Are you sure, the chip is dead?
Had a board with strange sound, where one of the bipolar caps was dead.

View attachment 576558

76489 is the correct part.

Are you sure, the chip is dead?
Had a board with strange sound, where one

76489 is the correct part.

Are you sure, the chip is dead?
Had a board with strange sound, where one of the bipolar caps was dead.

View attachment 576558

Just wanted to follow up and thank you for the tip! Swapped both caps, and the sound is perfect now.

 

[SamWhiskey]

nice