SN 76477 sound effect chip

[captain_haddock]

Have anyone here have extensive experience with SN 76477, sound effect chip. I believe it has 2 other sibling the SN76488 and SN 76489.

We can use this threan to explore the capability of this chip to produce many kind of sound effect, and most importantly for us to learn how those sound is created.

 

[barry]

Why are you bothering with an obsolete, 40 year old part? This is a fool's errand.

 

[Audioguru]

People who hoarded them sell them for a high price on ebay. But they might be fakes.

 

[BradtheRad]

I purchased a SN76477 'complex sound generator' at Radio Shack 35 years ago (only $2.99). The datasheet advised that we connect it to a configuration board containing about 20 switches, 20 capacitors and 10 potentiometers. These select a desired waveform and envelope:
* sine vs square
* one-shot vs repeating
* amplitude modulated vs freq modulated.
Etc.

I hoped I could see a simple way to start getting sounds out of the IC by hooking up a couple capacitors and a potentiometer adjust. However it required something more complicated than that. I ended up building a makeshift nest of wiring, with wires touching to act as switches. I tried a few arrangements in an effort to get sounds from it. I guess I didn't set everything correctly because I was disappointed. It's with my collection of half-finished projects.

 

[captain_haddock]

I've got 2 version of it the normal DIP and smaller DIP.

I've got all the circuit working, I use bread board, However I agree with brad, that we should be somehow make it simpler.

brad, do you still have the datasheet of it.

I used to show the locomotive steam thing to primary school kids, you know the rest of the story.

I purchased a SN76477 'complex sound generator' at Radio Shack 35 years ago (only $2.99). The datasheet advised that we connect it to a configuration board containing about 20 switches, 20 capacitors and 10 potentiometers. These select a desired waveform and envelope:
* sine vs square
* one-shot vs repeating
* amplitude modulated vs freq modulated.
Etc.

I hoped I could see a simple way to start getting sounds out of the IC by hooking up a couple capacitors and a potentiometer adjust. However it required something more complicated than that. I ended up building a makeshift nest of wiring, with wires touching to act as switches. I tried a few arrangements in an effort to get sounds from it. I guess I didn't set everything correctly because I was disappointed. It's with my collection of half-finished projects.

 

[BradtheRad]

brad, do you still have the datasheet of it.

It's in a folder somewhere in a box. It's several pages. Have you looked at websites which display datasheets?