The simplest DIY audio oscillator? not a 555 chip. reverse avalanche

hello so today we're going to talk about possibly the simplest type of oscillator you could possibly make out of electrical components I touched on this circuit last week on Red Bulls website to make a really simple hot glue gun light faraman if you want to make this it's really simple there's only actually free electrical components and all you need to do is just glue it all together the link is here but yeah I wanted to touch on this circuit more because I think it might be the simplest oscillator you could possibly make because all it has got is one light dependent resistor a transistor and a capacitor that's all it is and it's oscillating it's crazy right the only downside is it requires about 12 to 18 volts to run hence in the Red Bull video I put two 9-volt batteries in series to make 18 volts which gave it plenty of power to make it oscillate the thing about the circuit that makes it so simple is the fact that you're using a transistor not in a traditional sense you're actually using it in a mode called negative Evelynn more information on that in the description but this mode actually doesn't use the central pin you're only using two pins from the transistor and it's making it just completely jab out and go crazy and make a really nice sawtooth wave okay so apart from making a light theremin I thought would be interesting if we could just break board out the circuit to make a really simple oscillator with a pitch knob simple right the problem of making it work to put a jack in is you need a couple more components to make it run and it actually adds up to six components which i think is still simpler than something like a 5 5 5 oscillator and it sounds softer and nicer and it sounds in a way more analogue and less harsh because it's actually a sawtooth wave instead of a square wave I think it sounds really nice but you'll hear that soon so this lo and behold is the circuit simple right looks really easy and here's a list of components lovely you could probably get all of that stuff for well under a pound so we're gonna build this on something called strip board which is actually a board that has got strips of copper in and loads of lines means that you can make any circuit on it and just kind of make it up as you go the great thing is you don't need a whole board as well you just get your pliers and you snip out a thing like this which is actually a 12 hole by 16 whole piece of strip board easy right so I'm going to go over to the workbench and I'm going to solder together this circuit onto this piece of strip board this oscillator doesn't have any CV or anything but it won't be difficult to add and that might come later in another video but for now we're just gonna get like going so first things first is I'm actually going to sharpie the dots where the outputs go so this is going to be the ground that's going to be the voltage [Music] so first thing first we start with the resistors because of the smallest bit 1k and then 100 K goes so there we go that is the actual circuit finished it was that simple so the difference between this circuit and this circuit is not much at all so the difference is the potentiometer is there instead of a light dependent resistor there is a 1k resistor to stop the LED from burning out which the LED is kind of acting as the load that the speaker is acting so it makes the actual transistor oscillate and then the other 100 K is merely there to stop it from mixing with other oscillators when you put loads of these together but before we put loads of these together let's see if it actually works so I've just soldered a wire onto it to get the power into it so you've got lots of options to power these it needs at least 12 volts to oscillate so you could technically wire it into a modular synth power supply if you really wanted to just plug the ground into ground and the plus 12 volts so the 12 volts but a problem with 12 volts is you don't actually get that much range on the oscillator so what you could do is you can do the batteries 9 volt 9 volt and then that becomes 18 volts and you're plugged in or you could just get 15 volt or 18 volt like plug power supply and you wire that up to it I mean you've got loads of options but right now what I'm going to do is I'm going to use this which is just a variable power supplier that I picked up at a junk shop so I've just found a problem with it it won't actually work unless you cut the center leg off the transistor because if you soldered that center leg into the actual strip board then it makes too much surface area and it just kind of acts as like a really weird little ground and it won't actually oscillate so you need to snip that middle leg off don't solder it into the strip board so let's turn this up so you can literally build these in like five or ten minutes each so if we put together a couple more and pop them in a box and then let them all mangle together and just be little drones let's try it shall we [Music] [Music] so in around 20 minutes I've got them all soldered together look at that that's five oscillators in my hand so we just need to put these in a box solder the jacks together and yeah should be done [Music] so here it is five really simple oscillators in a very oversized box it's oversized because I'm going to put a sequencer in it soon so subscribe because that will be coming very soon as well but right now you can see they're all flashing around the back of the knobs and yeah let's just play with it these two actually have higher capacitor values but they're not quite right yeah I need to work out but you know [Music] [Music] [Music] [Music] out of bed brings up an egg a little angrier but yeah there's endless fun like trying to find like little patterns and you know nice harmonies within these even just these five austere layers so this method is really good because you could just keep on adding oscillators so the next video I'm going to do on oscillators it's just the question how many is too many I'm alone so that video will come in a couple of weeks and I'm going to give it a good go to try and answer how many oscillators is too many oscillators so please subscribe and then you can see when it comes off and stuff but yeah peace and throw one good one [Music]

Channel: LOOK MUM NO COMPUTER

Views: 261,481

Rating: 4.9461555 out of 5

Keywords: science, electronics, oscillator, DIY, synths, music, modular, synth, physics, transistor, stripboard

Id: zCTLeNxge54

Length: 10min 26sec (626 seconds)

Published: Mon Oct 16 2017

Reddit Comments

[u/[deleted]]

I bought 30€ worth of electronics after watching this. I'm going to have fun trying to make 3 of these next week.

[u/ScottFromCanada]

Very nice. Now I want to see him add voltage control.

[u/Pressingissues]

Wow what a great channel!

[u/webmiester]

End result sounded great.

[u/housefromtn]

Now I want to play a noise show where I make a shit load of these and just hand everybody one with a really long lead and see what happens.

[u/Bionic_Bromando]

How many oscillators is too many? Hard to say! The THX sound is bascially 60 oscillators going from detuned to tuned.