Sound Generator

Seems like I read somewhere that the 2812 was a Soviet version of a 555 but I'm not sure at all. Perhaps you could post the circuit and someone could see the design idea and recommend a substitute.

Hey guys,

The HT2812A is more then a simple oscillator, it is a chip designed by Holtek Semiconductor (www.holtek.com) to produce different sound effects for toys, etc.

There seems to be only one source for these, now that they have been obsolete for some time. www.usbid.com has many in stock, but I fear that may be the company asking for a 1000$ minimum order. If you send a really nice email saying that you just want one and that you will pay whatever for it, they will probably just send you one or charge a reasonable price for one.

Steve

steve is correct. I have seen the chip displayed I think as an 8-pin IC that produced oscellating sounds but I think the chip actually produces the sound and probably had an external circuit to make the output oscillate.

I also seem to remember reading on a model train forum about a circuit designed too produce the sounds of a steam engine and a whistle. I might even have a copy somewhere. Perhaps some of the model forums might have a schematic for the piston engine sound you want - using common parts. Good luck on this one.