SN76477 Sound Effects Generator
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- Опубліковано 10 вер 2024
- Found an old schematic that was quite cool back in the day. Old school analog / digital effects generator. In researching the scope of this chip, I saw some uploaded here that weren't pretty, decided to make one that is. So I put this together from scratch, was a fun project, enhanced with some lighting effects and cheapo parts from China - worked out pretty good after all.
Excellent! I made one of these as a kid in the 80's. My constructions skills weren't so great. I wonder if its still in my parents loft. I salvaged my chip from a Computer Battleships Game PCBA I bought as scrap from the back of one of my dad's electronics magazines.
Fabulous build.
I hooked something simpler up to some large speakers and an amp and woke up my parents on a saturday to the house launching into outer space...
My mothers only comment to my dad in bed about 8 am was Hold on Honey, we are on our way to the cosmos.
HA HA HA
I think I was 10 or 11 when I built it out of a SN76477
claudepgh - that's an awesome comment
Very nice work, I'm on that Ti chip since I'm a teenager, that was a long time ago...
Hello, could you explain what J1 and J2 mean in the diagram? We just need to know what it means to start the project. (upload.wikimedia.org/wikipedia/commons/9/9b/76477_Demo_Circuit-D.png)
Sure - from wiki
J1 is the External noise clock input. If this input is used SW17 should be open (or off). Waveform can be most any wave shape and most any frequency from a few Hz to about 2 mHz and can range from a half a volt to a maximum of five volts. Some very strange tones can be produced with a rather low frequency input to this jack.
- you can plug in a clock circuit like an external 555 astable / monostable timer for effects
J2 is the External VCO input voltage (selected or disabled by SW8. It can be most any wave shape and most any frequency from a few Hz to about several kHz and can range from a half a volt to a maximum of five volts.
- you can add an external signal generator to the circuit with this jack input, it can be a sinewave / sawtooth wave etc.
both of these jumpers i would use an RCA female phono plug for easy of connections, It adds to the variety but it'll work well without them as well. Good luck and have fun
@@disconer thank you Very Very much.
@@MarcioAlmeida Once you complete the project - throw some photos up :-) would love to see
Sounds nice :) I'm looking into the SN76477 myself at the moment. Any chance you could share that old schematic? Thanks!
en.wikipedia.org/wiki/Texas_Instruments_SN76477 - right off the wiki pages - good luck :-)
cool, so it's literally just the demo circuit? awesome! just got my chips, gonna start building soon. Any chance you have some closeup shots of your build?
No, I gave it to my Grandson as a gift, BUT I do have templates and notes if you're interested. The built-in preamp was a little wanting, so I fed it into a 5watt amp and definitely made it brighter. On my next build, it will be larger as the board I used was quite constraining. I used double throw rotary switches so I could add the LEDs, but that's wholly unnecessary - just for aesthetics.
Please show us the schematics you used.
I linked the schematic in the comments below, Fernando
There are a lot of schematics there. Did you use the bigger one? Thanks
LOL they updated the page - all the smaller schematics weren't there before - I built mine from the larger demonstration schematic. If you're going to build the demo version, let me know and i'll give you a couple of tips to make things go easier.
Thanks for replying friend! I plan to buid the larger schematic version! The complete datasheet demo version.
@@disconer I know this is a few months old, but I am also looking to build this demo. I'm interested in your 'tips to make things go easier'. Thanks!