[sdiy] low cost ic oscilator question

[harrybissell]

Free advise...

do NOT use the single gate schmitt trigger oscillator (40106)... it is not
really
stable enough... AND different manufacturers and different chips will give
DRASTICALLY different frequencies with the same components.

The advantage of the LC oscillator is that the frequency is a strong
function
of L and C (teehee) which tends to minimize the semiconductors as a drift
source.

I'd go with the two-gate or three gate oscillator myself...

H^) harry

Peter Blackett wrote:

> Hi,
> I'm thinking of modifying an old keyboard of mine  that presently uses a
> top octave generator ic , into using 12 seperate oscilators .
> I was wonderting if anyone had any recommendations as to what Ic I
> should use to generate the frequencies ?
> I was thinking of using an RC oscilator circuit rather than using tuned
> inductors.
> I know that I will loose the ability to shift the whole set of
> frequencies up and down with one tuning control , but I want to
> experiment with being able to change the frequency of each of the 12
> notes of the scale .
> also If the frequncy stability of the oscilators is good enough I might
> try having seperate osciltors for each note of the keyboard.
> I had thought about using the 40106 ic , but I don't know if this would
> be a good idea .
> I know Korg produced a Symphonic ensemble PE1000 keyboard many years
> ago, but I can't remember  which ic they used for the seperate
> oscilators .
> any advice is appreciated
> regards Peter