How the Adjustable Sawtooth Generator works

This video examines the operation of the Adjustable Sawtooth Generator you often see in my videos.
I learned how this circuit operates from w2aew's excellent circuit tutorial, found here: • #104: Circuit tutorial...
The unit I use is copied from Alan's circuit in the above video, except I have added a switch continuing different capacitors to give me a range of frequencies.
I have tired to build on Alan's tutorial video by using Flastad and by breadboarding some of the circuits in isolation in order to fully understand the operation of each set of components.
00:00 Introduction
02:48 Circuit Simulation
03:34 Capacitor Charging/Discharging
04:09 Capacitor Breadboard
04:34 Capacitor on the Oscilloscope
04:55 Current Sources
05:31 Diode Switch
06:24 Diode Switch LED Demo
07:13 Comparator with Hysteresis
10:34 Hysteresis LED Demo
11:45 Overview of the Full Circuit Simulation
15:57 The Adjustable Sawtooth Generator
17:00 Outro
Thanks to w2aew - check out Alan's channel:
/ @w2aew
The Falstad circuits shown in this video are here: bit.ly/3KRQEnT
I am no expert in electronics, I remain a curious hobbyist. However, I have always been fascinated in learning how audio electronics works. Disassembling various radios as a kid and eventually becoming interested in designing and building guitar effects pedals. I attempt to understand how these systems operate electronically, and due to this approach, I have picked up a few bits of theory along the way. If you're unsure about it, my best advice is just get started, mistakes and corrections (and the occasionally popped component) is how we learn. You win or you learn
If you found this useful, want to correct my knowledge or want to know more about my DIY pedals and test gear leave a comment below.
If you'd like to support my channel and get some cool stickers, you can find my Etsy Store here (I'll be adding some electronics kits in the future): www.etsy.com/uk/shop/MusicTec...

[@thomasmoran1211]

Youre such a great teacher. Ps keep making vids

[@MusicTechknowledgy]

Thanks for watching and for the positive comments. I do plan on making some more this year. 😊

[@zsagefox]

Glad to see you're still uploading! I found your channel a bit ago and it really helped me imagine actually making circuits and convinced me to place my first electronics order.

[@MusicTechknowledgy]

Thank you :) This is really great to hear. Excellent stuff.

[@tziirkq]

Great video, really well explained. Glad I asked!

[@MusicTechknowledgy]

Thank you :) I'm glad you asked too, and you've made me think about what other circuits could output a sawtooth.

[@jonnybishop]

Such a useful video. Really well explained.

[@MusicTechknowledgy]

Thanks, Jonny, Glad you found it useful. Really great to receive positive feedback. More videos coming soon. :)

[@LordPhobos6502]

Oh that's great! Love a good sawtooth!
Question, how does the constant current circuit portion(s) work? I'd love to see a breakdown of that :)

[@MusicTechknowledgy]

Thanks, Kaylee. Constant Current Circuits is an excellent topic for a future video. Perhaps a 'fundamental circuit for audio electronics' series.

[@codelicious6590]

OK fine, but can we make a pedal that will convert the guitar signal into an adjustable sawtooth wave?

[@MusicTechknowledgy]

Probably. I mean the square was bit is fairly easy with clipping. It’s the time it takes to charge discharge the capacitors being a function of frequency that’s going to be tough. Got me thinking now 👍