The quad Schmitt two input nAND is one of my favourite devices. It is so flexible. I once used one to generate pulse position modulation for a voice IR transmitter. One gate was used as a voltage controlled oscillator and the rest were used as a retrigerable monostable and a pulse generator. They also make a great simple circuit for an LED stroboscope. Again one as an oscillator, and two as a pulse width controller monostable. The output csn be used to drive an AC coupled gate of a power MOSFET providing driving to a super bright LED. I have used the circuit to inspect running computer fans.

Hey paul,I wanted to thankyou,I'm a disabled vet and I started watching your channel .I've been very interested in learning electronics and since I've been watching you I've learned a lot and now I've purchased a few things from banggood per your recommendations. I'm expecting delivering any day so I can start building a few of the project's you have shown.the 555 timing circuit,oscillators and the function generators.keep up with the videos Paul there very informative.I'm also navy mm,and a shellback

I've been reading resistors a lot recently. I'm finally getting to memorize the color code. It's a 20kΩ resistor.

$hit... electronic music making brought me to this place of wanting to build my own sound devices. Not only are you making me a geek, I can finally bond and communicate with my AF ret. electeical engineering Father who bought me my first soldering gun for Xmas.

're my last post on turning the Schmitt into a voltage controlled oscillator. The trick is to put a constant current pnp bipolar transistor in the feed back circuit, with a diode discharge in the reverse direction across the transistor. The diode provides a fixed discharge period and the transistor provides a linear voltage dependent charge period. With this topology the transistor is only biased on when charging the capacitor. In the charging mode the base of the constant current source can be driven from a simple common emitter transistor amp. Surprisingly this arrangement can be made to give a very linear voltage to frequency output. The circuit dates back to a project I did during work experience in my student days in the late 1970s. The idea was to produce an IR microphone link circuit for a radio transmitter. The receiver used a pulse count discriminatory also made from a few logic parts. From memory, the IR carrier frequency was 8 to 10 kHz. The receiver converted the pulse position modulation into pulse width modulation using another monostable, this was fillowed by an op-amp integrator and an eight pole Butterworth op-amp filter, used to seperate the audio from the carrier. The project requirement spec was that the microphone should work in full desert sunlight at a range of four metres. To this end an active load was used for the photo detector diode, a BPX65. A schmitt gate was used to provide an IR carrier detect squelch to suppress fm noise in the absents of a microphone transmitter, the squelch was also used to act as the Press to Talk control of the a 10 watt VHF fm transmitter. The biggest limitation of the circuit was that it generated popcorn noise under fluorescent strip lights. The advantage of PP modulation was that the ir LEDs were operated at If = 4 amps pulsed at somewhere between 1 to 10us pulse width. Yet the microphone 9 volt battery current was less than 20mA. I should point this is all from memory, so my figures are approximate. I would need to find my old lab book for the exact figures. The component count was relative high, but very low cost as most of the circuit was made from B series CMOS, namely CD 4093b. At this point I should apologise for this rambling post walk down my memory lane.

I’m working on 16 Oscillator Mod Rn for a sequencer. I love hearing colors and seeing sounds. Great Video

Thank you Sr!. Very instructive

Love the video. Learned so much from your channel

Great video. I must say that this circuit looks surprisingly like one of those electronic flickering LED tea light candles.😁

I still think the 555 makes the best simple oscillator

i am the 555th person who liked this video... :D but seriously, this is hillarious, i just built this, with a schmitt trigger that i recycled from my car, and played around a bit with the capacitor and resistor values, and it works A LOT better than expected, 22pf, both resistors 1k ohm, and it looked perfectly fine as far as i could measure (cheap 48 mhz logic analzer), that gave me a whooping 2 mhz square wave with almost exactly 25% off period. really amazing!

You can use an 82k(ohms) resistor and a 47uF capacitor 👍😃

As per your challenge to build this circuit -- ironically I stumbled onto your channel during my (ongoing) quest to learn how to build synthesizers. I have plenty of CD40106 chips to play with but I am lacking in fundamental EE knowledge, so I have been working with 555 chips to better challenge myself. If you have not seen "Casper Electronics DIY synth building. Part 1: Oscillators" here on KZfaq I invite you to check it out. Part 2 introduces some really fun sequencers and I am in the process of designing my own "daughterboard"-ish prototype to mix and amplify audio from my test circuits. Cheers!

As Always.... SUPPPERRRRBBBB!!!!!!!!

Another simple oscillator. I used to build 555 oscillators or with Opamps. With opamps is similar to this inverted buffer, having an aditional feedback resistor divider to the non-inverting pin. Resistor color code RED = 2, BLK = 0, BLK = 0, RED = x10, BRN = 1%

I believe the led and oscilloscope are loading the out put of the inverter. Ignoring breadboard capacitance and such; grounding unused input and taking output through another inverter gives stable results. But quazi-stable is the purty, lol.

Great Video. Speaking of Oscillascopes, what wpuld be your recommendation for a reasonably good/cheap scope for us hobiests. Emphasis on inexpensive. I tried a $20 kit, it didn't turn out well.

Even though there aren't many components in your oscillator, there is obviously something not working as expected. For instance the unstable duty cycle, missed pulse or whatever you want to call it, should not happen. Perhaps grounding the other inputs might solve the issue, but I'm not 100% convinced. As a friendly advice, making sure you've got a working circuit along with mathematical validation, if applicable, would be greatly appreciated. For example, using a RC circuit with a 74HC14 like presented here, the hobbyist should expect an output frequency in the range of 1/(RC) to 2/(RC), depending on the threshold range, threshold boundaries and VCC for instance. The CMOS family are bound to some specifications that are different for the TTL family would be an element that would worth to be mentioned thus incitating the hobbyists to search further more if they're planning to use such type of oscillator. One "funny" thing I noticed from your video clips is such that expressions like "Snap, what happened here ?", "That shouldn't be like that !", "I don't know what's going on !" and perhaps some others too, are censored and translated to "INTERESTING !". So if we hear you saying "INTERESTING", we'll know something most likely didn't go as planned. Don't get me wrong, your videos are serving their purposes, providing beginners with some information to get started with. To my personal taste, more specifically with electronics, theory and practice should be considered as a whole. If we don't master the theory, how can we validate what we put to practice ? Sometimes having a better understanding of the theory can help us at improving the troubleshooting. With the 20K and the 100uF we would expect a frequency of 1Hz or so. Seeing something in the 50-60Hz range on the scope would motivate most of us to raise the flag and investigate and perhaps conclude as you did with "INTERESTING" ! ;--)

I think the output would be more regular if you grounded all the unused outputs. Love the oscillator series!

Cool. Im using this to make a very simple synth. How do I add a pitch knob?

If I wanted to make this audible, where would i put the output?

Try connecting the inputs of the unused gates in the chip to either ground or VCC. 74 chips can be unstable if inputs are left floating.

I built the transistor circuit but for this circuit I need to order more parts. Is there no end? Chip and capacitor assortment in the store? Thanks for more fun stuff!

I'm new to all of this, so what you are creating it on is essentially a plastic printed circuit board? or is kind of acting as one for practicing circuits? What is this device? Edit: It's breadboard

If you use odd number of Schmitt-trigger inverters then in theory it should be enough to run unstable oscillator, but I don't have oscilloscope good enough to detect that frequency, can be megahertz range. ..and I just google it. yes, "few MHz" :)

resistor value =120 ohms

Tron is attacking the MCP! Drunk oscillator.

For everybody's interest, on the w2aew channel, there is a very good clip too on the Schmitt Trigger oscillator [ kzfaq.info/get/bejne/hNuInNd-sJmsg3U.html ]. I built the oscillator and as Alan did, I used it as my signal source for a time domain reflectometer. Worked like a charm. The timestamp is simply a marker where he explained how to compute the oscillator frequency.

any simple circuits that are made for driving piezo transducers?

No speaker with sound, sir?

👌👌🌹GOOD TICHING KARTE HO AP THANKS 👌🌹💖😂😆

good gob

how about cv

pov: you are a musician watching this

I won't be saying what value :) it look like 20k and the other way look like 120R

Plz make a 2.4ghz oscillator