Creating an oscillation circuit?

[tristancalvaire]

Hello there!

 

I've had a recent interest into learning more about circuitry, specifically within the realm of synthesizers. Unfortunately, my past experiences have been learning preliminary information in schooling (flow of electricity, calculating resistance of parallel circuits, etc.) and working with a microprocessor that could be programmed in C, so minimal circuitry knowledge was required for hookups.

 

I'd like to learn how to create a basic oscillation circuit that I could hook up to an amp or one of my Rokit monitors to form, say, a square wave. Unfortunately, I don't really understand how such a circuit would work.

 

For example, let's say I have one of these timers– http://www.radioshack.com/product/index.jsp?productId=2062595

How could I wire this in such a way that a 50:50 pulse wave is generated, with a variably controlled pitch via a potentiometer (and a changeable gain/amplitude/volume as well, if possible), to be sent to a 1/4' female jack (with preferably a loud enough gain to be audible, albeit I could likely gain it at the amp/monitor)? I don't particularly understand capacitors but I've seen people use them in simple designs such as this. I'd rather not simply follow a tutorial to build an oscillator, but rather start understanding the concepts behind it.

 

Thank you for any info you might have, resources I should check out or other discussion forums specialized in this subject!

[ski]

Do a search online for "555 circuits" and you'll find a wealth of information. BTW, there's only so much you can learn about oscillator design from using an integrated circuit because all of the hard work is being done by the chip. If you really want to understand how oscillators work on a conceptual level, get some books on basic circuit design and start reading up. Who knows, maybe there are even some tutorials online you could find.

 

Radio Shack used to sell these circuit books by author Forrest M. Mims (or Mimms). You might still be able to get them and if you can, I highly recommend them to give you ideas about circuit design and applications. Aside from that, there are probably a trillion books out there from which you can learn the fundamentals of electronics and circuit design.

[tristancalvaire]

Do a search online for "555 circuits" and you'll find a wealth of information. BTW, there's only so much you can learn about oscillator design from using an integrated circuit because all of the hard work is being done by the chip. If you really want to understand how oscillators work on a conceptual level, get some books on basic circuit design and start reading up. Who knows, maybe there are even some tutorials online you could find.

 

Radio Shack used to sell these circuit books by author Forrest M. Mims (or Mimms). You might still be able to get them and if you can, I highly recommend them to give you ideas about circuit design and applications. Aside from that, there are probably a trillion books out there from which you can learn the fundamentals of electronics and circuit design.

Thank you for the advice Ski- I'll certainly look into picking up some reading.

 

For now, I've been looking this over–

http://www.kpsec.freeuk.com/555timer.htm#astable

 

And I'm curious– would it be easy to add onto the circuit to allow for pot control of the pulse-width? How would I go about doing it?

[ski]

You're welcome.

 

Regarding pulse width, It tells you right on that page how to control it. It's referred to as "duty cycle". So you'll need a diode and a pot.

[tristancalvaire]

You're welcome.

 

Regarding pulse width, It tells you right on that page how to control it. It's referred to as "duty cycle". So you'll need a diode and a pot.

 

I noticed that- but I thought it was simply putting in a fixed diode which'd statically change the pulse-width. If R2 is the pot controlling pitch, what'll be controlling the duty cycle in that circuit- R1?

[ski]

I think so.