These circuits usually won't work, except you are living next to a radio station and you are using a very long (4-5m) antenna. For the RF amplification you will need an RF transistor, which can handle those high frequencies. When you use a LM386 as an audio amp, make sure you use this 10µF capacitor between Pin 1 and 8 AND at least a 10µF cap directly at pin 6 and 4 and also an 10µF cap at pin 7. The LM386 can't handle this high amplification without a buffer and will otherwise produce loud squeaking noises. The other thing is: FM signals are not easy to demodulate. With discrete components this would be very hard...in these days you'll need a PLL FM-decoder IC or something like that. For testing purposes you can use something that is called (i don't know the english translation!) "edge discriminator". This is done, just by adjusting the variable capacitor next to the exact wanted frequency, as you are doing. But this sounds awful and if you turn the cap 1 tenth of a mm to far, you will hear nothing. You also need to keep the wire lengths as short as possible....you can't do it on a breadboard. The wires of your coil are too long. If you would solder it together directly, you would get much better results. Try to use silver wire, instead of copper wire for the coil! But even though: the results will be "experimental" and not satisfying...
Because all those click bait thots and or dumb channels with mediocre content hahaha “we are going to do a little bit of math “ I’m like wtf hahaha good stuff though I work on bikes so wiring is fun wanted to learn more about stuff like this so started watching this channel it’s great! Keep up the great vids
I hate slow videos. This is awesome speed. You can scan the content very fast thanks to it and then stop when neccessary when trying to do the same project by yourself.
Just came across this channel I've watched several of your vids so far I'd have to say it some the better stuff I've seen on TH-cam. Keep it up mate you have some good stuff on here!
Suggestion: To access those tiny trimmers, you can make your own trimmer driver from a small plastic paint brush handle. Just file the tip of the handle down to the shape and size that fits the trimmer cap, and now you have the correct driver with the added bonus of it not damaging trimmers like metal drivers can.
Thanks so much for this video ! I graduated with a degree in Physics and had to take a course in Analogue Circuits. Didn't do to well, but I'm hoping to start projects on my own.
Great video! I would recommend that you stay away from electrolytic capacitors for ac decoupling of your power rails. They're polarized and the noise can occur in both directions. I'm not really familiar with this particular circuit, I would probably shoot for a .1uF ceramic cap instead of that 470uF electrolytic one, though.
A common technique is to also put decoupling capacitors directly across the power inputs of your components like your op-amp. This can be more effective than just decoupling the power rails, because your breadboard itself could be responsible for some of the noise.
This is legit my favorite channel... I am always looking forward to new content being put up :D I'm an upcoming engineer/inventor and I love to build random stuff so naturally I'm going to love watching this stuff lol... A couple things I would really love to see in later videos are something solar powered (solar fire starter, solar taser, etc...) and I would really like to see some kind of give away cuz I would totally want a souvenir!!! Also I was curious where are you from/living?
thank you for helping me understand [rf], by seeing it and hearing what you said it finnaly sank in, sometimes it just takes the right teacher for me to understand something.
LM386 is not an OP Amp.. it's an actual linear audio amplifier and are commonly found in non stereo devices like a fax modem to drive the internal speaker or some toys that make sounds. Some PC speakers used them early on (one for left speaker and one for the right speaker) but now they use ond of the TDA IC varients for stereo sound amplification. Most of those cheap varible caps use plastic sheets to change the capacitance. same for modern dual gang tuning caps. The one you are using is a trimmer.and is VERY touchy, For the best band coverage you should use an actual tuning cap. That big .22uF cap is an AC line cap, it's overkill for this application but it will work lol
If I wanted to start learning about all of this type of electronics ( because I know absolutely nothing ), where would be a first place to start? I find this topic interesting and I’d love to learn more but I just don’t understand much of it, but I want to
Great info but please insert a few commas and full stops, periods in your delivery as everything just rolls into a complete mush, many thanks for info.
Wow this is amazing especially on a breadboard. The audio amplifier part I’m good with. Could somebody please explain the principle behind the left part of the circuit? How is frequency converted into amplitude for the op amp to further amplify?
@J W I actually found out - this not a high quality FM circuit, but basically the way it works is that there is a principle called Injection Locking that says that a small signal will "lock" on to a Collpits oscillator and change its intrinsic frequency which is normally determined solely by the LC tank. So the antenna keeps changing slightly the intrinsic frequency of the LC tank. In turn the amplitude across the tank varies. The load resistor is voltage divided with the tank, so the voltage across it changes. Filtering the carrier is not necessary because the transistor amplitude stabilizes to audio frequency (you can see this last bit only through advanced math, it's not intuitive and usually doesn't happen; usually if you want an envelope you need something like a diode envelope detector). ( ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6774035 ) For it's simplicity this the HARDEST by far FM circuit to understand & the least intuitive. It's performance is also inferior to the usual ones.
@J W Thanks JW - same to you. The subject is pretty hard, but i'd recommend "Principles of Electronic Communication Systems" by Louis Frenzl. Unfortunately it's super expensive, but the 3rd edition (one before last) can be found used on Amazon for a reasonable price.
Hey, cool video :D Just one thing: when filming the vlog type intros, you might want to wait a second before you stop the camera after saying a line xD
I'm still surprised that the receiver is still doing so well! because breadboard is not really suitable for radios and transmitters. yes it can work (proves it now!) but watch out for that next time... healthy and kind regards from the Netherlands! Rob
That’s cool! I’m in eighth grade and actually kind of understood some of this stuff. I am looking to become successful me sort of an engineer when I’m older. Are there any courses or kits that you recommend to learn something like this
Must be honest. You didn’t write dots to separate wires connected, and the wires that don’t connect. makes the whole diagram false, hard to read, and complicated to create. Considering this is science we know how bad a small thing can make a circuit. ASIDE FROM THAT IT WAS A GREAT VIDEO THUMBS UP STILL.
Why does this circuit work? The LC part of the circuit is not modulating the signal, because the frequency of FM radio is changing. I believe it's only modulating the "centre" of the spectrum, so the sound is incomplete.
Plz use crystal instead lc tank for simple fix frequency fm and am receiver . Or using fix Freq 555 ossilator as transmitter ! I want to make pet Coller tracker .
excelente amigo eres un genio yo he armado tu circuito del transmisor de radio fm y funciona perfectamente y tiene un muy buen alcance y a hora voy armar el de tu circuito de radio para ver que tal funciona los transistores 2n3904 no los consigo aquí donde vivo pero voy a probar con los c945 y el chip lm386 tampoco lo puedo conseguir pero voy a reemplazarlo por un tda2822 que es un chip estéreo pero lo coloco a funcionar en puente como dice la hoja de datos para que quede mono y suene mas fuerte con los 3.5 voltio saludos desde Venezuela amigo son muy buenos tus vídeos sigue así
@@guillermoviramontes851 sin funciono pero después de derramar varias lagrima porque el circuito es muy sensible a la capacidades parásitas y toca jugar un montan con la bobina hasta encontrar el punto donde funciona mejor
Your two transistors in the receiver form a circuit like a tunnel diode (at much less cost) the bias is critical, a pot would be good to adjust your 22K bias resistor to form a regenerative receiver.
@@levirizkisaputra3729 A tunnel diode is a special type diode that has negative resistance at a certain level of bias Voltage, meaning it can amplify and cause oscillation even at very high frequencies.
In this radio the two transistors will fight each other to allow current flow, so one of them will conduct then the other transistor will conduct so that there will be oscillation and gain. I would use a 50K or 25K variable pot. (resistor) to set the bias point.
@@levirizkisaputra3729 The sound is demodulated in what is called a slope tuner, not a true FM demodulator. To hear the sound you tune close to the station (not on the peak) then as the FM signal changes frequency with the modulation, audio sound can be heard. But it is really AM reception with some static, not true FM.
Could you make a video about something like... van der Graaf generator? Or other generator of static charge Or maybe on converting a shematic to a protoboard and how to convert it to a prefboard
If you do go to 6 Volts, you will have to put a variable resistor for the 22k one, I would go with 100k and start at high resistance adjusting down until you hear some noise or signal meaning you have regeneration. you could then measure the resistance you find best and put in a fixed resistor if you want to.
These circuits usually won't work, except you are living next to a radio station and you are using a very long (4-5m) antenna.
For the RF amplification you will need an RF transistor, which can handle those high frequencies.
When you use a LM386 as an audio amp, make sure you use this 10µF capacitor between Pin 1 and 8 AND at least a 10µF cap directly at pin 6 and 4 and also an 10µF cap at pin 7. The LM386 can't handle this high amplification without a buffer and will otherwise produce loud squeaking noises.
The other thing is: FM signals are not easy to demodulate. With discrete components this would be very hard...in these days you'll need a PLL FM-decoder IC or something like that.
For testing purposes you can use something that is called (i don't know the english translation!) "edge discriminator". This is done, just by adjusting the variable capacitor next to the exact wanted frequency, as you are doing. But this sounds awful and if you turn the cap 1 tenth of a mm to far, you will hear nothing.
You also need to keep the wire lengths as short as possible....you can't do it on a breadboard. The wires of your coil are too long.
If you would solder it together directly, you would get much better results. Try to use silver wire, instead of copper wire for the coil!
But even though: the results will be "experimental" and not satisfying...
You're one of the best science diy channels on TH-cam..why aren't you more famous??
Shreyas Jani y science without rockets, explosions and metal working is not the best deal on TH-cam.
he can build nuclear rocket
@@dalmatiko sure man. When?
Because all those click bait thots and or dumb channels with mediocre content hahaha “we are going to do a little bit of math “ I’m like wtf hahaha good stuff though I work on bikes so wiring is fun wanted to learn more about stuff like this so started watching this channel it’s great! Keep up the great vids
99Mhz ±10 is almost the entire FM range! I giggled.
102.10
I had the same thought, but still impressive that he arrived at that estimation. :D
hehehehe..........
105,6 😊
@@krek420I listen to 102.1 every morning
Aww I wanted to see a test of the homemade fm transmitter broadcasting to the fm receiver he made. Great video though.
Sawyer H same🙍
You can see a test of fm reiver and transmitter I made
its quite illegal to broadcast fm radio without a licence. Unless you keep it under something like 1mV at 1A
Your explanation is awesome, but you do it so fast. Maybe slow down a little bit. Great job.
TH-cam videos have a speed setting.
Too hyper for me, a little more calmer amd this would be perfect.
I hate slow videos. This is awesome speed. You can scan the content very fast thanks to it and then stop when neccessary when trying to do the same project by yourself.
I know nothing about electricity, I enjoyed this video. subscribing!!
oops I was already subscribed
Just came across this channel I've watched several of your vids so far I'd have to say it some the better stuff I've seen on TH-cam. Keep it up mate you have some good stuff on here!
your my favorite person i dont know personally
awe thanks :)
Can't wait to try this thank you for providing a product list for beginners!
Always a good day when I get to brake out the 2N3904's!
Suggestion: To access those tiny trimmers, you can make your own trimmer driver from a small plastic paint brush handle. Just file the tip of the handle down to the shape and size that fits the trimmer cap, and now you have the correct driver with the added bonus of it not damaging trimmers like metal drivers can.
+N1RKW that's a great idea! I will do that! Thank you so much!
Glad to help! It's a technique I've been using for years, and it's worked well for me.
Thanks so much for this video ! I graduated with a degree in Physics and had to take a course in Analogue Circuits. Didn't do to well, but I'm hoping to start projects on my own.
And thats how we slap stuff together. Awesome Video!!!
Yup. definitely one of my top two channels. Videos are very good and informative.
I gave you a thumbs up, but, I can't comprehend what you are saying because you are talking so very fast. Great concept. I like it. Thank you.
excellent job pacing yourself!
I love this video. It explained this in detail so I can finally progress with my self learning. Thank you!
Great video! I would recommend that you stay away from electrolytic capacitors for ac decoupling of your power rails. They're polarized and the noise can occur in both directions. I'm not really familiar with this particular circuit, I would probably shoot for a .1uF ceramic cap instead of that 470uF electrolytic one, though.
A common technique is to also put decoupling capacitors directly across the power inputs of your components like your op-amp. This can be more effective than just decoupling the power rails, because your breadboard itself could be responsible for some of the noise.
would a 4.7uf one work also 50 volt ??
This is legit my favorite channel... I am always looking forward to new content being put up :D I'm an upcoming engineer/inventor and I love to build random stuff so naturally I'm going to love watching this stuff lol... A couple things I would really love to see in later videos are something solar powered (solar fire starter, solar taser, etc...) and I would really like to see some kind of give away cuz I would totally want a souvenir!!! Also I was curious where are you from/living?
This guys underrated
i will be very happy to see you as my teacher
thank you for helping me understand [rf], by seeing it and hearing what you said it finnaly sank in, sometimes it just takes the right teacher for me to understand something.
That was amazing, I'm going to watch it again right now.
Kudos to the pen!
LM386 is not an OP Amp.. it's an actual linear audio amplifier and are commonly found in non stereo devices like a fax modem to drive the internal speaker or some toys that make sounds. Some PC speakers used them early on (one for left speaker and one for the right speaker) but now they use ond of the TDA IC varients for stereo sound amplification.
Most of those cheap varible caps use plastic sheets to change the capacitance. same for modern dual gang tuning caps. The one you are using is a trimmer.and is VERY touchy, For the best band coverage you should use an actual tuning cap.
That big .22uF cap is an AC line cap, it's overkill for this application but it will work lol
Wow your writing is such wonderful
Good video - I have an FM video like yours on You Tube, using the same circuits. You did a great job in explaining how to make it.
could you link me? i am struggling to get mine to work
Always informative!
Goes through it very quick . Good though
If I wanted to start learning about all of this type of electronics ( because I know absolutely nothing ), where would be a first place to start? I find this topic interesting and I’d love to learn more but I just don’t understand much of it, but I want to
subbed due to a shout out from backyard scientist. loving what I see so far.
+Dash Cam Trucker thank you! :D
Very good
Genius!!!!
Hi brother i make your theremin very good thank you im fron Brasil👍👏👏👏
Your video is awesome. Congratulations for your work
This guy is going somewhere in life
Great info but please insert a few commas and full stops, periods in your delivery as everything just rolls into a complete mush, many thanks for info.
I really dig the mini coil
+Tesla Explorer haha thanks :D
Time to make your channel official!
+Lucas how?
Keystone Science ask your network to verify you
+Turky oh, I don't have a network... or at least I don't think I do
networks take alot of your add revenue, you would know. nice vid.
"Once your channel gets 100,000 subscribers, you’re eligible to submit a request to TH-cam for a verification badge." I just figured it was a button.
have you got a schematic? please send the picture thanks. :D
So nice and well
I watched this whole video and have fucking idea what's going on. Maybe i should learn some of this shit.
Same
You should :)
Jimmy Turner blue film
Jimmy Turner blue film
Wow this is amazing especially on a breadboard. The audio amplifier part I’m good with. Could somebody please explain the principle behind the left part of the circuit? How is frequency converted into amplitude for the op amp to further amplify?
@J W I actually found out - this not a high quality FM circuit, but basically the way it works is that there is a principle called Injection Locking that says that a small signal will "lock" on to a Collpits oscillator and change its intrinsic frequency which is normally determined solely by the LC tank. So the antenna keeps changing slightly the intrinsic frequency of the LC tank. In turn the amplitude across the tank varies. The load resistor is voltage divided with the tank, so the voltage across it changes. Filtering the carrier is not necessary because the transistor amplitude stabilizes to audio frequency (you can see this last bit only through advanced math, it's not intuitive and usually doesn't happen; usually if you want an envelope you need something like a diode envelope detector).
( ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=6774035 )
For it's simplicity this the HARDEST by far FM circuit to understand & the least intuitive. It's performance is also inferior to the usual ones.
@J W Thanks JW - same to you. The subject is pretty hard, but i'd recommend "Principles of Electronic Communication Systems" by Louis Frenzl. Unfortunately it's super expensive, but the 3rd edition (one before last) can be found used on Amazon for a reasonable price.
Hey will you please help where I learn electronics like you and which is the best book for learning
Get your hands on an Arduino kit or something similar. Learning code alongside with modules is probably one of the best ways to learn in my opinion.
Hey, cool video :D Just one thing: when filming the vlog type intros, you might want to wait a second before you stop the camera after saying a line xD
I'm still surprised that the receiver is still doing so well!
because breadboard is not really suitable for radios and transmitters.
yes it can work (proves it now!) but watch out for that next time...
healthy and kind regards from the Netherlands!
Rob
my youtube bell is only for best youtubers like you
CoAcOn1
Your Great.
Make Some more videos about flybacks transformers, I love The range
Ops I mean I love flybacks transformer videos
love how the numbers in your email are the Fibonacci sequence 😂
+raz Y thanks xD
Wow he is a genius
That’s cool! I’m in eighth grade and actually kind of understood some of this stuff. I am looking to become successful me sort of an engineer when I’m older. Are there any courses or kits that you recommend to learn something like this
Nice video!
Nice explanation
you are a fing blessing
This. Is. Amazing. Ty for this
Great explanations for a noob, very detailed. Awesome. Exactly the typa stuff I wanna make some day
You better not be cheating with that inspire lol
Hey, great video. Thanks for doing these. Very impressive math. :)
Holy shit! I think I have the same scope as you.
Could I use a cristal and resistor in the oscilator part of the circuit?
Also amazing vid!
The way you hold the fountain pen... :)
good work dude, keep it up!
Can I apply 9 volt instead of 3.5?
Or 3 volts instead of 3.5?
Great video
Excellent! Can you add AM/SW to this set?
Must be honest. You didn’t write dots to separate wires connected, and the wires that don’t connect. makes the whole diagram false, hard to read, and complicated to create. Considering this is science we know how bad a small thing can make a circuit. ASIDE FROM THAT IT WAS A GREAT VIDEO THUMBS UP STILL.
keep up with great work 😊😊
Why does this circuit work? The LC part of the circuit is not modulating the signal, because the frequency of FM radio is changing. I believe it's only modulating the "centre" of the spectrum, so the sound is incomplete.
Plz use crystal instead lc tank for simple fix frequency fm and am receiver . Or using fix Freq 555 ossilator as transmitter ! I want to make pet Coller tracker .
Thanks for the video, awesome job . I'm trying to build but I didn't understand very well, which wire you used. Can tou tell me please. Greetings.
can you make a review on the pam8610 amplifier
Brother I would like you doing a vdo on simple AM receiver with crystal oscillator
excelente amigo eres un genio yo he armado tu circuito del transmisor de radio fm y funciona perfectamente y tiene un muy buen alcance y a hora voy armar el de tu circuito de radio para ver que tal funciona los transistores 2n3904 no los consigo aquí donde vivo pero voy a probar con los c945 y el chip lm386 tampoco lo puedo conseguir pero voy a reemplazarlo por un tda2822 que es un chip estéreo pero lo coloco a funcionar en puente como dice la hoja de datos para que quede mono y suene mas fuerte con los 3.5 voltio saludos desde Venezuela amigo son muy buenos tus vídeos sigue así
Te funciono?
@@guillermoviramontes851 sin funciono pero después de derramar varias lagrima porque el circuito es muy sensible a la capacidades parásitas y toca jugar un montan con la bobina hasta encontrar el punto donde funciona mejor
Can I use bc547 transistors instead
Your two transistors in the receiver form a circuit like a tunnel diode (at much less cost) the bias is critical, a pot would be good to adjust your 22K bias resistor to form a regenerative receiver.
What is the purpose of tunel diode?
@@levirizkisaputra3729 A tunnel diode is a special type diode that has negative resistance at a certain level of bias Voltage, meaning it can amplify and cause oscillation even at very high frequencies.
In this radio the two transistors will fight each other to allow current flow, so one of them will conduct then the other transistor will conduct so that there will be oscillation and gain. I would use a 50K or 25K variable pot. (resistor) to set the bias point.
@@mrdovie47 I have question sir, where is demodulation happen? May guest is capacitor and resistor before LM386 IC
@@levirizkisaputra3729 The sound is demodulated in what is called a slope tuner, not a true FM demodulator. To hear the sound you tune close to the station (not on the peak) then as the FM signal changes frequency with the modulation, audio sound can be heard. But it is really AM reception with some static, not true FM.
what is the value of the potentiometer?
Whats the sensativity of the antenna ? Can you get in weak stations, low powered FM ones also ??
Do you have a printable version of the schematic you used?
What’s the name of the wire
Wire
Nice pen
hi can i use mini 0.1microfarad ceremic capacitor.plzz reply. thank you
Could you explain the positive feedback inputted into the tank circuit? My concept on that is very shakey...
Great vedio sir...
Do I have to use LM386?
Best of the best ty so much
How is working RF section.
I’m surprised it worked on breadboard at all, but that might explain why the osc measurement was off.
What's the difference between variable trimmer capacitor and potentiometer.?
Can I use one of them instead of another. If not can you explain.?
How much tall of the antenna?
Cool fountainpen
Could you make a video about something like... van der Graaf generator? Or other generator of static charge
Or maybe on converting a shematic to a protoboard and how to convert it to a prefboard
How do you increase the sensitivity of the tuning circuit?..like by changing the variable resistor to the one that was wide range
I try it but no luck. Maybe because i use bc546 transistors?
Will it work with a 2N2222A transistor instead? it has the same pinout and a similar name so I assume they are related in some way. SOME ONE RESPOND
Some People Say it works with 2n2222 and some say it doesnt, i just would recommend you to try and u will see
@@kubakrawczuk7450 Idk it might blow 😲Might be worth it though I have hundreds of 2n222a transistors.
@@kubakrawczuk7450 ehhh... also I don't have a lot of components for this project so I won't do it.
Compare the data sheets of the 2n3902 & the 2n2222a. You might have better gain (he) with the 2n2222a.
Now just one more thing, do you think I could use a 10pF variable cap instead of a 22pF?@@arthurwellsjr.4082
hey please tell me more about the capacitors used
how strong of a vacuum did the refrigerator compressor pull
Hi... i wanna ask it is possible if i change the value of input voltage, from 3.5V to 6V and what is the effect ?
If you do go to 6 Volts, you will have to put a variable resistor for the 22k one, I would go with 100k and start at high resistance adjusting down until you hear some noise or signal meaning you have regeneration. you could then measure the resistance you find best and put in a fixed resistor if you want to.
Very interesting but you do talk too fast for me to take it all in, so please slow down and you would be an excellent teacher. Thanks for the video.
Are the transistors operating as a double tuned amplifier (bypassing a narrow bandwidth)?
Super bro thanks
I've just decided on college right now too! what college did you choose?