DIY AC Waveform Function Generator Kit - The Learning Circuit

[@Otakunopodcast]

Good on you for emphasizing the use of safety glasses! Many years ago, back in my days of youth and stupidity, I used to not wear them. Then one day a hot splatter of solder (or was it flux? well whatever it was, it was hot, splattery, and went airborne) came within inches of hitting my eye. Ever since then I never solder (or do anything involving tools, screws, little pointy bits that could suddenly go airborne if you're not careful, etc.) without them.

[@terrypetersen74]

I'm an old man I'm happy to see that electronics engineering what's younger people ain't going to waste

[@qwkimball]

$9 signal kit, $1400 scope, priceless video.

[@ghostmexi007]

amazing video ty youtube for the recommendation honestly love this type of channels of DYI proyects especially engineering ones love the content

[@scottdebruyn7038]

Good video! I'd like to point out that barely being able to hear the 10-100 Hz signal with the speaker is a function of the response curve of that small speaker. Typically, a small (1-3" diameter) speaker response drops off quickly below 400-500Hz. Some will, like yours, drop off below 1KHz. Also most of these inexpensive speakers have nasty resonance peaks that practically blow your ears off when you hit them... Sounded like yours hit resonance around 3KHz. If you ever need a technical bit expounded upon, hit me up at Dutchman Electronics. Happy to help! I'll keep watching and may kibitz here in the comments from time to time. :)

[@maker_karen1785]

Thanks for the added information!

[@TechOwnSolutions]

I have one of these, and its working fine at lower frequencies.❤️

[@edwardreichard3852]

Hi Karen I’ve been watching your videos for sometime now and enjoy them, I was honking of taking courses to be an electronic technician, I was wondering is there a demand for that position if so , any tips I what you could recommend

[@MrCardeso]

Thanks, Karen. Nice demonstration!

[@jonka1]

Replace the 330 ohm resistor with a 500 ohm pot. This makes it possible to set up a much better sinewave.

[@neo256mb]

I can only find potentiometers that have 3 legs. is there one that has only 2 legs ? the 330ohm has only 2 holes. you mean a 500 ohm Potentiometer yes? if it's 3-terminal which leg should be cut off?

[@jonka1]

@@neo256mb What I did was bend the middle leg over to make contact with one of the outer legs and solder them together. You then have a two leg variable resistor. The other way would be to cut off one of the outer legs and use the two as your variable resistor.

[@neo256mb]

@@jonka1 thank you. It does not matter if I solder the middle leg to the left or the right outer leg?

[@jonka1]

@@neo256mb It will only affect the direction you turn the pot to increase or decrease the resistance.

[@hoofheartedicemelted296]

I asked a question on your The Learning Circuit video, Transformers in Action : Tesla coils regarding how to construct a circuit to pulse a frequency in 3 second intervals. This video has brought me one step closer to understanding the process. The integrated circuit can be a bit confusing so I may search through your videos for a more specific explanation. They seem to be multifunctional so it may take time to understand them properly and apparently the only video I watched that built a completed circuit used 3 of these IC's.

[@YDKMPablo]

Great video guys! But you would like to show the exact frequency using Keysight's measure function next time.

[@paulcohen1555]

Can't you sync the scope for a stable display?

[@ChrisLocke1969]

interesting... makes me wonder, are there any scopes that include audio feedback?

[@davidcross30]

Ooooo. I just got a second hand analog crt oscilloscope so this is perfect timing.

[@ArtsyEngineering]

Great video!

[@edwardreichard3852]

Excuse me😂, not honking but thinking lol!

[@mavericklast2555]

What the name of your grip for the board and the fumes extractor your using?

[@oswaldjh]

The power jack and potentiometers are mechanical points of failure. Bending the leads flat to the PCB will make them almost impossible to replace later.

[@ChrisLocke1969]

may be a newbie question, but how can you attach LEDs directly to AC current??

[@greengohm]

Full-bridge rectifier + some resistors to limit the current - but that's assuming you have enough LEDs to "cover" most of your AC voltage. In other words plenty of LEDs, otherwise the resistor wattage will be massive and you'll waste a lot of power due to resistor heating up. This is very inefficient way, but the simplest. Check out BigCliveDotcom's channel for disassembly of many LED bulbs for inspiration :) And be careful!

[@ChrisLocke1969]

@@greengohm it just seemed odd how she just plugged LEDs right into the signal generator. Thx for the great explanation, but did she convert to DC? i missed it. 😉👍

[@maker_karen1785]

@@ChrisLocke1969 For this kit, the output is AC, but it's very low voltage. Maybe 5V. The LED pack usually takes 3V. So when the wave rises to 3V, the LEDs have enough power to turn on. Luckily, the 5V isn't enough to burn out the LEDs, but if I let it run for a long time, pushing the voltage and current beyond the ratings of the LEDs(up to 5V, and beyond 20mA) would shorten their lifespan.

[@andye2005]

All diodes work quite happily on a.c. just depends on application. A rectifier diode converts a.c. into d.c. and so on. An LED is no different apart from different voltage drops (not so good for a rectifier) There is a nice demo (see link) when a series of LEDS were connected as a bridge rectifier and fed at first with a simple dc supply manually swapping over the connections, then with a function generator with a nice slow sine wave, it clearly shows the operation. kzbin.info/www/bejne/bImmlXaKhriYiNk about 4 mins in and then 8 mins in. The little function gen is operating as a switch on square wave, so it's no different to connecting led to a battery. You just have to ensure that you don't over current the LED, so a current limiting resistor is advisable. The other waveforms will do much the same. As shown the sine is not really a true sine at all.. . That kit is pretty notorious for problems, and not working to the spec, but it usually does something which is the main point. Andy

[@hydroalternation]

love the board vise

[@freakvan911]

great stuff karen!!!!!

[@ninetailscosmicfox5585]

I was wondering if a HPF on the sine wave function would help round it out more, but with variable frequency that's probably a nightmare to work out

[@Fullchaos40]

Could do with an op-amp integrator (just two components op amp and capacitor) to curve the triangle wave bit more. Would just need a capacitor that can handle the high end well enough.

[@mtz5582]

What to study minimum and be able to do this.

[@richgolfs]

What is the integrated circuit that you were using? I did not hear you mention that

[@maker_karen1785]

I got the kit off Amazon. Here's the link: smile.amazon.com/Weewooday-Generator-Function-Frequency-Adjustable/dp/B08LGV8ZKP

[@bornach]

It is likely a fake XR2206. It is okay for use in hobby applications, provided you stay below 9V. Kainka Labs has a video examining this kit in detail and found that the signal becomes unstable at 12V and above. That wouldn't happen with a real XR2206

[@jeran42]

I did this kit once! I was having a great time until i put the potentiometer knobs on before the case, and the gnomes used magic to keep the knobs stuck very fast on them. In my attempts at removing the knob, i broke the board, and never got a chance to try it out. :(

[@maker_karen1785]

Oh that's so sad! That's totally something I'd do.

[@bornach]

The PCB is fairly simple. You could probably create it on protoboard using the circuit diagram that came with the kit.

[@prateekchowdhury3337]

Create your own on a perf board

[@nickwild1457]

Wow 😳 this is beautiful..,

[@taintedmeat9740]

I think that AC/DC shirt may have a double meaning!

[@whobetterthankyle]

Great video Karen, crappy product unfortunately. The sine wave was awful, and why didn't the amplitude adj impact the square wave? Are there any other frequency generator kits you'd recommend?

[@jonka1]

The circuit does not cater for changing the square output. It is a simple pull-up at logic levels.

[@relaxingnature2617]

Safety glasses reminds me of ..Crazy Russian Hacker .."Safety is #1 priority"

[@technophile01]

Hi. you did not give the diagram or the name of the integrated circuit used ?!

[@PhillipRhodes]

I'm pretty sure it's an XR2206 IC. I have what appears to be the exact same kit (or very nearly identical at least), and that's what mine is based on. See, for example: www.amazon.com/Weewooday-Generator-Function-Frequency-Adjustable/dp/B08SMB6DRM/

[@adailyllama4786]

It is in a kit: www.amazon.com/dp/B08LGV8ZKP/ref=cm_sw_r_cp_apa_glt_fabc_QDGDCMFD14SVJ01A2HPP

[@bornach]

It's most probably a fake Xr2206. It's okay for this application just don't use it above 9V

[@soumiksarkar1988]

This could also be designed using simple analog circuit . 1st stage - Astable multi vibrator using OP-AMP (50% duty cycle) , 2nd stage - integrator circuit to have triangular signal with suitable value of feedback resistor for desired amplitude of the signal , 3rd stage - another integrator circuit for sinusoidal signal with suitable value of feedback resistor ..

[@andye2005]

Better still the good old 555!

[@soumiksarkar1988]

@@andye2005 but 555 will not give u the complete square wave as it has not any negative input supply it gives a pulse +Vcc to 0 ... we r talking about the complete square wave that is +Vcc to -Vcc and that can be generated by OP-AMP .

[@andye2005]

@@soumiksarkar1988 if you are going to post process the signal after the osc (whatever it is) then it does not really matter if the osc swings +/- or not. You can deal with any requirement for +/- swing then. Something like the 555 just gives you more options to play with. (drop in the cmos version and you get a bit more voltage range tom play with if needed.)

[@CABohol]

Nice!

[@adailyllama4786]

Let the magic begin 1:15

[@relaxingnature2617]

Is the output AC or DC ?

[@paulperano9236]

Sine and triangle are AC. Square is more DC that's ON/OFF, ON/OFF, ON/OFF ... The kit is very cheap and not that great. However if all you need is varying tones for testing audio circuits or DC pulses for timing/logic circuits - who cares if its not amazing. If you want to test speakers, then get a cheap amplifier kit as this generator is low power and NOT designed to drive speakers.

[@peatmoss4415]

Fix that hair do!