New Octave Circuit Design

[grapefruit]

Hi,

I just started to play around with building a website last night, and I've been using LT Spice for a couple of weeks, so I thought I'd post a design I did using LT Spice.

http://members.optusnet.com.au/stewpye/Transistor%20Octave1.jpg

R10 Would actually be a pot wired for gain control. I couldn't find a pot in the LT Spice Library. R5 would be a pot in series with a resistor also. I haven't built this circuit so I'm sure it need a few tweaks. The section that does the octave is Q1 and Q2. It's based on a swatooth to triangle converter from the book "Electronic Musical Instruments" by Norman Crowhurst.

The interesting part is that with lower input levels you get a pretty pure sine wave, then as the input level goes you get a gentle hump and then what is shown in the picture, and even more...  If anyone wants the spice file please PM me. I might put it up once I tweak it and get a website going.

Cheers,
Stew.

[StereoKills]

Link doesn't work...

[Mark F]

Link doesn't work...

+ 1

[grapefruit]

I took it down. I've been playing with the circuit a bit and will put it back up when I've got it sorted.

The heart of it is basically the same as a moog saw to triangle converter.
Here is the heart of the circuit.
http://members.optusnet.com.au/stewpye/octavegen1.jpg

Stew.