[sdiy] Simplest stuff to begin with, and a few questions

[Robotboy8 at aol.com]

I noticed you mentioned variable caps in your oscillator... most people try
to avoid this technique for synths.  There's nothing wrong with building an
oscillator this way, but it'll be hard to get voltage control of the rate.
It will probably work fine as an LFO, but you may find there are better
oscillators to use as your main VCOs.

I realize this, but I'm not really looking for CV at this point - more at 
something simple enough that I can actually finish it, and something with a low 
enough parts count I could build many of them (I'm looking at 8, with xfades 
between each set of two for real-time morphing by hand).  In other words, at 
this point I'm mainly just trying to see if this proposed oscillator will indeed 
oscillate.  And if all it's good for is an LFO, at least it'll be a working 
LFO - as opposed to the countless unworking audio-frequency oscillators I've 
started and never finished.

Basically, it's two transistors turning each other on and off.  I'm not sure 
if the jack is placed in the right place.  I'm not sure where to get variable 
caps.  I'm not sure what value the resistors next to the caps should be.  I 
don't know why there are so many damn types of transistor, other than NPN and 
PNP - and I"m unsure if I have those switched around.  All I know is that I need 
an SPST switch to turn it on and off, basically - I know what the components 
do, but not much about the laws surrounding them.  I've tried and I've tried 
to comprehend them, but it's just too much at once as soon as I try to do more 
than one thing with Ohm's law.... but then, I tend to think better by doing 
than staring, so I'm trying to jump in and do something I can actually get done.

As for the signal levels, you're right but if I design all the modules myself 
they'll all be working at +/-4.5v anyway.

Schematics now online:
www.geocites.com/tranoschem/oschem.gif
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