When I was in high school, I worked in an engineering lab. One of the engineers sometimes liked to listen to country music. Another engineer didn't want to hear it. He stuck an antenna wire on an RF signal generator, tuned it to the radio station frequency, and slowly turned up the amplitude. This was done stealthily, of course, so the other engineer had no suspicion. The music just faded away.
Hi, Bro! I saw a random guy the other day on RUclips, and his process is intuitive. 1. He hand-sketched on the board. 2. Made appropriate drills. 3. Then he laid very very thin wire along his sketch. Then, he put that whole PCB carefully on a surface which he can increase the temperature (he used an iron box). Gradually as temperature increased, wires began to melt and the wiring thing was done. That was cool.
I'll take a look at this video later, but lemme say thank you so much for brinign back life into such an old topic. Back in school in 2016 i successfully but an AM transmitter only using 2n3904 Transistors (Hartley Oscillator), and i wanted to build the receiver to go along with it, but none of my receivers ever worked. I've tried SO many configurations without "cheating" or using too complext ics, i wanted it to be a receiver using NPN transistors too, but the main issue is idk how to properly measure or deduce why my circuits never worked. Wanna say thanks again, i feel like there's hope for my project again. If yall are interested i can get the schematic of the transimtter that worked at lest. Thanks @GreatScott!
hey i had the same issue, it's real frustrating maybe try this circuit www.talkingelectronics.com/projects/TheTransistorAmplifier/images/Fig71bd.gif you don't need the transformer, just connecting the speaker from 3v to the collector of the last npn transistor works fine. And make sure to put >22uF decoupling capacitor across the supply so there's no unwanted noise. 2n3904 and 2n3906 transistors have worked fine for me. Only problem is that the output sound is really small. Maybe you can replace the speaker with like a low value resistor and then add a class A amp after the last stage. (don't tinker with the other stages, doesn't make the sound louder, i tried yesterday) hope it helps :)
@@Kevin-jz9bg Thank you for the reply! it REALLY means alot to hear that there are others that tinker/deal with this kinda stuff given im a noob. I'll definitely test this. Here is the transimtter i used to build it. Its based on a radio project from a RadioShack 300 projects in 1 kit. I took their morse code transmitter and added my computer speaker input into it. i broke it up into 3 stages because it was easier to draw lol. bubbamachina.files.wordpress.com/2018/04/am-transmitterpng.png?w=666&h=1024
@@bubbamachina1308 thanks for sharing!! I'll try to build it and let u know how it goes!! For the inductor in the hartley oscillator, can I just take an am inductor from my am radio and tap the center? (it's 55 turns on 1cm * 10cm ferrite rod) I'm a total n00b too but hey "it's super cool, which I think should be the only prerequisite for doing science." - Physics girl U shud check out talkingelectronics.com for a buttload more of projects :) i recommend buying some generals purpose npns and pnps in BULK and just building whatever seems interesting: www.talkingelectronics.com/projects/TheTransistorAmplifier/TheTransistorAmplifier-P2.html?ref=driverlayer.com
The addition of this vowel will certainly minimize the number of possible candidates.... Not widen it 🤣. Just like how adding science to arts does the same thing.
@@jamess1787 what do you mean "minimize candidates"? The more the movement covers, the more interested parties there can be involved. It's not like a person is forced to do anything in particular with a program, it's just about encouraging and fostering learning and skills
The "easiest" AM transmitter would be to feed both the oscillator and the audio through capacitors, connect the output of both capacitors together, and send it through a common-collector amplifier with no bias voltage on the base. The effect is a carrier signal that changes amplitude based on the audio strength.
@@greatscottlab Hallo, greetings from Venezuela. Thank you very much for your videos they're so cool and helpful! I've been researching a little bit about IC that could function as a replacement for the TA7642 of your AM RX and I found out this two ICs the TA7640 and the TA7641, would you recommend either one of them to be used in place of the TA7642? Thank you very much for your time and help on the matter, I really wish you're having an excellent day! Tschüss! :)
I had to do a report on AM in our communications class. Built the same transmitter with the 555 and paired another 555 to send a square wave into the transmitter (pretty much broadcast a tone over AM) it blew everyone's mind in class. Teacher was amazed haha. Also, they have crystal oscillators for am. Litterally plug an audio source to it, make an antenna and you're good to go.
I know this is very old now by RUclips standards, but i built a similar deal as this with a car battery and a 1k pot, a 100uF cap and a 10k pot . it works very well and my sdr picks it up all over the dial. you leave the 10k pot at full and tune the 1k pot to the desired frequency. I ordered the circuit you suggested anyway and cant wait to start using it instead.
wireless technology is always cool, can't wait when Great Scott will soon build up a remote control circuit with just a basic components locally available without a complex IC. and i always dream about it
Thank you so much for this video, i built 4 fm transmitters earlier and non of them were working, now i built this ne555 am transmitter and it works!! It sounds bad as hell but at least ive got something. Thank you again
This is the dream! I've been wanting to build an RF switch (both RX and TX) for YEARS and I couldn't. Even my professors back in my uni days wouldn't help. Yes using RF modules would solve it, easily, but defeats the whole purpose. I want to build it from scratch!
That would be cool, especially in the manhattan style circuit board for good measure lol Come the day of the Internet apocalypse, it could prove to be very handy.
would´ve been cool to build an actual oscillator based on discrete components instead of using an timer IC ;) Back then, there were no ICs inside tube radios 😁
@@brankotdk it was a "rocket radio" from the ealry 60's. It was a crystal radio (the crystal in this case was the earphone itself) which actually works like a diode but can only pass a very low current as far as i know. Radios from the 30's worked similar, but had a amplifier tube and and speaker. And of course no 555 timer IC 🤣
I like simple. I used a 6888 vacuum tube, a tank circuit, and a TTL oscillator, with a triode to drive the screen grid. Works great. I get about 5 watts of RF.
AM is also a fun way to mess with ultrasonics... if you have a 96kHz sampling PC sound card, it can directly output ~30-40kHz narrowband signals to drive a low-cost ultrasonic emitter. The low frequency compared to RF makes a demodulator circuit simple. This even works with no circuitry in the transmitter at all, some early TV remotes used an ultrasonic tuning fork struck by a hammer to send button presses without batteries.
Antenna coil using a coil form made from a business card- use a small piece of hookup wire between the former and the ferrite rod to space it so that it can be moved for tuning. 1 transistor colpitts oscillator + modulation into the base. 1 transistor reciever... into an earpiece using another ferrite rod coil on former with fixed capacitor. maybe a movable tickler feedback winding to cause regeneration
In spite of what someone else posted earlier, you can operate an unlicensed AM radio broadcast station in North America by an agreement made between Canada, U.S., and Mexico as follows: Unlicensed broadcasting - 100 mW DC input to final amplifier with a 3-meter maximum length radiator, no license needed, may be measured at edge of campus for school stations.
Actually, running that 555 output into a tank circuit (probably with a buffer amp) to make it resemble a sine wave and modulating the power supply voltage with the audio would work pretty well.
I remember once years ago I built some type of radio/microwave receiver. It consisted of three quadruple bowtie antennas tuned for around 2GHz and three germanium diodes to rectify the received energy to a signal. I then connected that to two integrated circuits operational amplifiers LM358 (cascading operational amplifier with 22KHz bandwidth) if I remember correct. And that was supplied by a bipolar voltage of +/- 1.5v. 2 batteries. The aim of that receiver was to receive any kind of radio and long microwaves. And it did work. I could catch FM signals, mains 50Hz distortions and the microwaves from the wifi. It was heard like ticks in my soviet era 150 ohm headphone. The receiver contained NO coil.
Enjoyed video regarding the transmitter build. It's probable that your circuit likely complies with Part 15.209 if you need to keep the radio relatively close to the transmitter. Your video will certainly be of interest to the would-be Part 15 broadcast enthusiast who wants to build their own transmitter before graduating to one of the more costly, high performance Part 15 AM transmitters. Thanks for sharing.
For anybody wanting to learn more, the amateur radio relay league (arrl.org) has tons of great information on their site about how to design transceivers. They also have information on how to get ham certification inside the United States, which is required if you want to be able to transmit over any significant distance
You use 2 transistors for the transmitter! One for rf and the for signal that controls the current off the rf transistor emitter. The receiver do not need any but you can use a transistor that you could use as a volume control. And it will be a lot clearer!
5:12 You could probably get away with frequency modulation with the 555 and the radio if you added a high Q LC series resonant circuit to the 555 in series with a proper length tuned antenna. The resonator resonates when the 555 drives it near resonance but increases in impedance as it drifts away. Duty cycle modulation would also work as it a duty cycle further from 50% will have less power in the fundamental and more power in the harmonics that get filtered out.
AM ALL THE WAY!!! Awesome video and very informative about how Amplitude Modulation works and how to make an example circuit!!! Thanks for another extremely educational opportunity for learning more about RADIO 📻!!!
You can't reach 100MHz regular broadcst frequency with 555 but you can easely produce phase modulation with it, that can be demodulated by a FM receiver. If you buy an old army wolky-talky (various models have various bands but in general they start at around 30MHz to around 55MHz-60MHz and small ones (several kilograms that is, sized as a small netbook with 3 times its thikness) are ususaly from around 40MHz to 47MHz) and find 555 variation that can reach 40MHz (both are accessible) you can try it.
In the U.S. (no idea in other parts of the world, but probably similar) without an F.C.C. class 'C' license (now known as a "technician class"), you can not operate a radio transmitter, A.M. or F.M. with a total broadcast output of greater than 20 watts or a transmission range of greater than 20 miles. This is *only* when using a transmitter whose design and commercial manufacture have been pre-approved by the F.C.C. In the U.S. this is from the regulation congress passed in 1987 that allows you to use your citizens band radio, and radio controlled models and toys without an F.C.C. class 'C' license. An addition was added to that regulation in 1995 to include the unlicensed use of your cell phone (your cell phone is just an F.M. radio transmitter and receiver). A non approved transmitter such as a hobby built unit can not exceed 2 watts total RMS at the antenna, or about a 500 yard broadcast radius unless the actual transmitter part of the circuit is a sealed unit with F.C.C. pre-approval. Whether or not some F.C.C. official is hiding in the woods to catch you broadcasting at 5 watts, I leave to your imagination. As for using a square wave generator (555 timer IC) as a broadcast Carrier Wave, all you need to do is scope the CW signal at the RX antenna to see why it's a crappy idea. You may be "sending" a square wave, but the receiver antenna sees a spikey, bipolar, saw tooth (more like an inverted shark's fin) wave form. This make's it extremely difficult to filter out the overtones and sub harmonics caused by the spikes.
Actually, hex inverter, eg. UB4069 will be simpler, work better than that and draw less current. Even if Xtall be used as harmonics we can reach up to 300MHz with very clear transmission (AM or FM). Just make sure make a very simple class A amplifier with 2SC9018 transistor For receiver, please don't build bird nest version like this, just attach in PCB with wide ground plane, it will give a huge stability. Greetings from Indonesia 🇲🇨
With more power and a amateur radio license you can use the AM transmitter and receiver you built to talk to people in other countries. With the right antenna and only 5 Walt you can talk to people far away.
My simple transmitter based on 6p3s tube. With main frequency generator on 6j8. For modulation i built simplest tube amplifier.... This thing can produce 7W of radio signal. It's Powerful for such construction.
you can also use a crystal oscillator used for microprocessor clocks in the 80s to make a transmitter as it contains the entire oscillator. also as more and more of the analog fm broadcasters go digital there will be the space opening up and the fcc may soon care less about the part 15 rules unless your transmitter should somehow cause a pacemaker to malfunction and cause a heart attack or completely drown out emergency responder communications.
Why do it easy when it can be done more complicated. A TL072 can be used as colpitts Oscillator and OP with variable amplification done by a JFET in the featback. The NF signal goes to the gate of the JFET. The SA602 or SA612 ist a mixer with build in oscillator. Both gives real AM without any detours.
Interesting. I made an Am transmitter with the 555 a couple years ago. As I remember 600- 700 KHz is about the max you can set up the 555 to oscillate at. Mine did work. It had horrible harmonic issues and was all over the place. I had used an audio transformer to modulate the carrier. Did it work, yep but..... not exactly clean at all and likely not worth the effort to filter....
@@shriniwashasefirst select an empty fm channel for ex you choose 94.5mhz station in reciver press button of remote and with the help of screw driver rotate a black thing you will see in wrapped around coil. You will hear a around 1000hz tone. find in pcb from where around 1000hz tone is generated. From there add audio input or audio can be input in series with battery. Audio can be inputted from mobile phone using aux cable
Awesome project man 👏👍. Why don't you do an project with 24bit DAC with Raspberry Pi and with options like DRC control, Equaliser, ... This will be interesting and useful DIY audio hobbyists like me. Kindly consider this.
I tried to make this one, I used 12v as power supply and I tested t 3m away and when I am touching the output the signal increases and as I don't the signal disappears, why is that so? Can someone explain me?
Hey Scott! Awesome video, but this AM waveform on 3:04 is not the best honestly. I get it, it's hand drawn, but it really got to a mix of AM and FM :) As a tip for the next time, you could've drawn straight vertical lines with pencil to indicate where peaks of carrier are and should be in resulting signal :)
When I was in high school, I worked in an engineering lab. One of the engineers sometimes liked to listen to country music. Another engineer didn't want to hear it. He stuck an antenna wire on an RF signal generator, tuned it to the radio station frequency, and slowly turned up the amplitude. This was done stealthily, of course, so the other engineer had no suspicion. The music just faded away.
“Honey, why does the country music stop whenever we drive by the engineering annex” XD
Strictly not legal to jam a frequency but its a lab so one cares
haha I would notice something odd's going on that would trigger my need for investigations 😅 unless it jams the whole fm range
@@hadibq It just faded out and back in like atmospheric conditions. This was AM radio, so a strong carrier overwhelmed the detector.
@@lavakumar5944 Exactly and of course, when this is discovered by the first engineer, payback can be a real b****!
Getting boxes to talk to boxes. Coolest stuff on earth
Hi, Bro!
I saw a random guy the other day on RUclips, and his process is intuitive.
1. He hand-sketched on the board.
2. Made appropriate drills.
3. Then he laid very very thin wire along his sketch. Then, he put that whole PCB carefully on a surface which he can increase the temperature (he used an iron box). Gradually as temperature increased, wires began to melt and the wiring thing was done.
That was cool.
Fun fact: this video is not sponsored by JLCPCB.
😆
Uh ok
Faktycznie :D
Nooooooooooooo!
Then u are a regular viewer like me
1:39 That's my 3D printed radio video!! :) Thank you for sharing.
Oh great
Nice
I'll take a look at this video later, but lemme say thank you so much for brinign back life into such an old topic. Back in school in 2016 i successfully but an AM transmitter only using 2n3904 Transistors (Hartley Oscillator), and i wanted to build the receiver to go along with it, but none of my receivers ever worked. I've tried SO many configurations without "cheating" or using too complext ics, i wanted it to be a receiver using NPN transistors too, but the main issue is idk how to properly measure or deduce why my circuits never worked. Wanna say thanks again, i feel like there's hope for my project again. If yall are interested i can get the schematic of the transimtter that worked at lest. Thanks @GreatScott!
hey i had the same issue, it's real frustrating
maybe try this circuit
www.talkingelectronics.com/projects/TheTransistorAmplifier/images/Fig71bd.gif
you don't need the transformer, just connecting the speaker from 3v to the collector of the last npn transistor works fine. And make sure to put >22uF decoupling capacitor across the supply so there's no unwanted noise.
2n3904 and 2n3906 transistors have worked fine for me.
Only problem is that the output sound is really small. Maybe you can replace the speaker with like a low value resistor and then add a class A amp after the last stage. (don't tinker with the other stages, doesn't make the sound louder, i tried yesterday)
hope it helps :)
@@Kevin-jz9bg Thank you for the reply! it REALLY means alot to hear that there are others that tinker/deal with this kinda stuff given im a noob. I'll definitely test this. Here is the transimtter i used to build it. Its based on a radio project from a RadioShack 300 projects in 1 kit. I took their morse code transmitter and added my computer speaker input into it. i broke it up into 3 stages because it was easier to draw lol.
bubbamachina.files.wordpress.com/2018/04/am-transmitterpng.png?w=666&h=1024
@@bubbamachina1308 thanks for sharing!! I'll try to build it and let u know how it goes!!
For the inductor in the hartley oscillator, can I just take an am inductor from my am radio and tap the center? (it's 55 turns on 1cm * 10cm ferrite rod)
I'm a total n00b too but hey "it's super cool, which I think should be the only prerequisite for doing science." - Physics girl
U shud check out talkingelectronics.com for a buttload more of projects :)
i recommend buying some generals purpose npns and pnps in BULK and just building whatever seems interesting: www.talkingelectronics.com/projects/TheTransistorAmplifier/TheTransistorAmplifier-P2.html?ref=driverlayer.com
I'm glad we're going from STEM to STEAM, arts are important and can be a great part of science!
The addition of this vowel will certainly minimize the number of possible candidates.... Not widen it 🤣.
Just like how adding science to arts does the same thing.
@@jamess1787 what do you mean "minimize candidates"? The more the movement covers, the more interested parties there can be involved. It's not like a person is forced to do anything in particular with a program, it's just about encouraging and fostering learning and skills
The "easiest" AM transmitter would be to feed both the oscillator and the audio through capacitors, connect the output of both capacitors together, and send it through a common-collector amplifier with no bias voltage on the base. The effect is a carrier signal that changes amplitude based on the audio strength.
I'm glad you posted this, because i want to create one for my tube radios
You're welcome :-)
Your unmodulated AM signal should only be 1/2 of max amplitude, or 1/4 of max power. Much better sound quality !
Thanks for the tip :-)
Thank you Pepe the Frog
why this man is posting his link in every comment of great scott किन हह
@@projectnepal8482 why this man is posting in every comment किनभने
Which city are you from post me
I've been looking at making something like this for the past week! Amazing timing
Perfect!
Hello sir. I am a 13 yrs old electronics enthusiasts and I need some help. Can I contact you. I don't think so bcoz I think he would be busy.
@@greatscottlab
Hallo, greetings from Venezuela.
Thank you very much for your videos they're so cool and helpful!
I've been researching a little bit about IC that could function as a replacement for the TA7642 of your AM RX and I found out this two ICs the TA7640 and the TA7641, would you recommend either one of them to be used in place of the TA7642?
Thank you very much for your time and help on the matter, I really wish you're having an excellent day! Tschüss! :)
I had to do a report on AM in our communications class. Built the same transmitter with the 555 and paired another 555 to send a square wave into the transmitter (pretty much broadcast a tone over AM) it blew everyone's mind in class. Teacher was amazed haha.
Also, they have crystal oscillators for am. Litterally plug an audio source to it, make an antenna and you're good to go.
Make an Antenna! thats what I have been trying for the last 30 years!
I know this is very old now by RUclips standards, but i built a similar deal as this with a car battery and a 1k pot, a 100uF cap and a 10k pot . it works very well and my sdr picks it up all over the dial. you leave the 10k pot at full and tune the 1k pot to the desired frequency. I ordered the circuit you suggested anyway and cant wait to start using it instead.
A project that I can afford! Great!
Enjoy!
wireless technology is always cool, can't wait when Great Scott will soon build up a remote control circuit with just a basic components locally available without a complex IC. and i always dream about it
Stop dreaming, start doing.
Will you be posting more videos for the "trying circuits i found on the internet " series?
Yep, there will be more episodes.
Oh yeah, please! 😍
I'm looking forward to it!
@@greatscottlab speaking of wireless communication. Try making a tv transmitter
👍❤❤
More analog circuits, please! Thank you for your work :)
Thank you so much for this video, i built 4 fm transmitters earlier and non of them were working, now i built this ne555 am transmitter and it works!! It sounds bad as hell but at least ive got something. Thank you again
Great .. Next challenge : Make ONE Switch radio control circuit (Rx and Tx) with basic transistor and crystal circuit .. no ICs ... 100m - 1km
Hello Mr. Walid I am your subscriber when I was 14 years old now I am 18 thank you for your lessons I learned a lot from your videos
This is the dream! I've been wanting to build an RF switch (both RX and TX) for YEARS and I couldn't. Even my professors back in my uni days wouldn't help.
Yes using RF modules would solve it, easily, but defeats the whole purpose. I want to build it from scratch!
It's great to see an electronics master challenging another electronics master :)
Maybe you can do this video together? :)
That would be cool, especially in the manhattan style circuit board for good measure lol Come the day of the Internet apocalypse, it could prove to be very handy.
Yes, regenerative plz and LC tank osc. Am waiting for that
would´ve been cool to build an actual oscillator based on discrete components instead of using an timer IC ;)
Back then, there were no ICs inside tube radios 😁
My first am transmitter had only one transistor and worked fine!
@@brankotdk I´ve seen AM receiver which had no active electronic components at all.
Only a coil, few capacitors and resistors and a crystal earphone.
@@MultiWirth sorry for my English... That was probably detector recever. Works without battery. You need also diode (I used germanium diode).
@@brankotdk it was a "rocket radio" from the ealry 60's.
It was a crystal radio (the crystal in this case was the earphone itself) which actually works like a diode but can only pass a very low current as far as i know.
Radios from the 30's worked similar, but had a amplifier tube and and speaker.
And of course no 555 timer IC 🤣
@@MultiWirth the titanic reciever
I like simple. I used a 6888 vacuum tube, a tank circuit, and a TTL oscillator, with a triode to drive the screen grid. Works great. I get about 5 watts of RF.
I know I'm a bit late, but do you still have the schematics for your circuit?
Its a magic "Summon the FCC" circuit!
Well, he's in Germany, and HAM licenses there are called "Amateurfunk Prüfung", so I'm sure he'll be fine. I'm sure he's got enough funk to pass it.
Not at all. Not enough power to attract attention even if he lived in the US. Yes I have a HAM license.
Nein. Night von Deutschland.
i think its an overkill to use ICs for AM communication. it can be done with a few transistors with great quality
AM is also a fun way to mess with ultrasonics... if you have a 96kHz sampling PC sound card, it can directly output ~30-40kHz narrowband signals to drive a low-cost ultrasonic emitter. The low frequency compared to RF makes a demodulator circuit simple. This even works with no circuitry in the transmitter at all, some early TV remotes used an ultrasonic tuning fork struck by a hammer to send button presses without batteries.
Antenna coil using a coil form made from a business card- use a small piece of hookup wire between the former and the ferrite rod to space it so that it can be moved for tuning. 1 transistor colpitts oscillator + modulation into the base. 1 transistor reciever... into an earpiece using another ferrite rod coil on former with fixed capacitor. maybe a movable tickler feedback winding to cause regeneration
I'll use this for my thesis next year, thanks Scott
In spite of what someone else posted earlier, you can operate an unlicensed AM radio broadcast station in North America by an agreement made between Canada, U.S., and Mexico as follows:
Unlicensed broadcasting - 100 mW DC input to final amplifier with a 3-meter maximum length radiator, no license needed, may be measured at edge of campus for school stations.
That was WERY interesting. Thank you for taking time to investigate and record this!!!
Actually, running that 555 output into a tank circuit (probably with a buffer amp) to make it resemble a sine wave and modulating the power supply voltage with the audio would work pretty well.
Amazing! Finally a project I can build without much hassle ;)
We've got you surrounded! Come get an HF band license
~ Federal Communications Commission
@@bat4 I WILL NOT GET A CLASS 1 HAM RADIO LICENSE I WILL NOT GET A CLASS 1 HAM RADIO LICENSE
Did you watch the whole vid already
@@serignebah4788 i watched it 4 days ago
Perhaps that will be from ZouTube not youtube
This was a VERY fun video. and I learned about a kit vendor I never knew about, kiwiCo. Thank you!
I remember once years ago I built some type of radio/microwave receiver. It consisted of three quadruple bowtie antennas tuned for around 2GHz and three germanium diodes to rectify the received energy to a signal. I then connected that to two integrated circuits operational amplifiers LM358 (cascading operational amplifier with 22KHz bandwidth) if I remember correct. And that was supplied by a bipolar voltage of +/- 1.5v. 2 batteries.
The aim of that receiver was to receive any kind of radio and long microwaves. And it did work. I could catch FM signals, mains 50Hz distortions and the microwaves from the wifi. It was heard like ticks in my soviet era 150 ohm headphone. The receiver contained NO coil.
Enjoyed video regarding the transmitter build. It's probable that your circuit likely complies with Part 15.209 if you need to keep the radio relatively close to the transmitter. Your video will certainly be of interest to the would-be Part 15 broadcast enthusiast who wants to build their own transmitter before graduating to one of the more costly, high performance Part 15 AM transmitters. Thanks for sharing.
Everyone is proud of Great scott !!
Finally I can build this and give it to my dad ❤️😍🤗 thanks 😊 great Scott
Hope you enjoy it!
I Really Love your videos, There more knoledgable than my 4 years Engineering Degree ...
For anybody wanting to learn more, the amateur radio relay league (arrl.org) has tons of great information on their site about how to design transceivers. They also have information on how to get ham certification inside the United States, which is required if you want to be able to transmit over any significant distance
I got a simple project that i can built this week, thanks :)
Have fun!
Nice little boombox Panasonic Ambience stereo is a very nice feature for their boomboxes
You use 2 transistors for the transmitter! One for rf and the for signal that controls the current off the rf transistor emitter. The receiver do not need any but you can use a transistor that you could use as a volume control. And it will be a lot clearer!
I used a single transistor in one design.
يا خبر أبيض . ..لله دررك يا هندسة....يا خبر أبيض ....
RF circuits are absolute fun.
I think I'm on right channel thanks Scott for great videos
5:12 You could probably get away with frequency modulation with the 555 and the radio if you added a high Q LC series resonant circuit to the 555 in series with a proper length tuned antenna. The resonator resonates when the 555 drives it near resonance but increases in impedance as it drifts away. Duty cycle modulation would also work as it a duty cycle further from 50% will have less power in the fundamental and more power in the harmonics that get filtered out.
Install a coax cable with a sma connector so you can improve the antenna.
This was my capstone project!
Great Work! Greetings from 🇮🇹
you can make a collpits oscilator and modulate it with an iron core transformer and it works fine
Finally, a project I can make without the FBI have suspicions
Very cool sponsor this time!
AM ALL THE WAY!!! Awesome video and very informative about how Amplitude Modulation works and how to make an example circuit!!! Thanks for another extremely educational opportunity for learning more about RADIO 📻!!!
😁👍
Thinking quickly, GreatScott constructs a homemade AM radio transmitter, using only some solder, a microphone, and a 555 timer.
You can't reach 100MHz regular broadcst frequency with 555 but you can easely produce phase modulation with it, that can be demodulated by a FM receiver. If you buy an old army wolky-talky (various models have various bands but in general they start at around 30MHz to around 55MHz-60MHz and small ones (several kilograms that is, sized as a small netbook with 3 times its thikness) are ususaly from around 40MHz to 47MHz) and find 555 variation that can reach 40MHz (both are accessible) you can try it.
In the U.S. (no idea in other parts of the world, but probably similar) without an F.C.C. class 'C' license (now known as a "technician class"), you can not operate a radio transmitter, A.M. or F.M. with a total broadcast output of greater than 20 watts or a transmission range of greater than 20 miles. This is *only* when using a transmitter whose design and commercial manufacture have been pre-approved by the F.C.C. In the U.S. this is from the regulation congress passed in 1987 that allows you to use your citizens band radio, and radio controlled models and toys without an F.C.C. class 'C' license. An addition was added to that regulation in 1995 to include the unlicensed use of your cell phone (your cell phone is just an F.M. radio transmitter and receiver). A non approved transmitter such as a hobby built unit can not exceed 2 watts total RMS at the antenna, or about a 500 yard broadcast radius unless the actual transmitter part of the circuit is a sealed unit with F.C.C. pre-approval. Whether or not some F.C.C. official is hiding in the woods to catch you broadcasting at 5 watts, I leave to your imagination.
As for using a square wave generator (555 timer IC) as a broadcast Carrier Wave, all you need to do is scope the CW signal at the RX antenna to see why it's a crappy idea. You may be "sending" a square wave, but the receiver antenna sees a spikey, bipolar, saw tooth (more like an inverted shark's fin) wave form. This make's it extremely difficult to filter out the overtones and sub harmonics caused by the spikes.
Great job GreatScott! I'm trying to learn how an rf transmitter and receiver functions so that I can understand better how to trouble shoot them.
Nice video , that single ic remembered me of its grandmother the zn414 from the seventies.
Great video..! Now I can test my old vacuum tube radios if they can still recieve sound!
THIS IS THE VIDEO I HAVE BEEN WAITING FOR!!!!!!! THANK YOU SCOTT!!!!!!!!!!!!!!!!!!!!
You're welcome😁
Thank you. Yes make these kinds of videos that is simple and easy to do and videos about electronic basics
That moment when messing with the knob actually sounds good 5:35
To much information 😂
Actually, hex inverter, eg. UB4069 will be simpler, work better than that and draw less current.
Even if Xtall be used as harmonics we can reach up to 300MHz with very clear transmission (AM or FM).
Just make sure make a very simple class A amplifier with 2SC9018 transistor
For receiver, please don't build bird nest version like this, just attach in PCB with wide ground plane, it will give a huge stability.
Greetings from Indonesia 🇲🇨
Cool project!
Thanks😁
What how four day ago?..?
@@TECHiHOBBYIST Patreon.
I think so I am late
But here marking my attendance
And enjoying the video
Hope to get some deep soviet codes via this signal lol🤣
1:39 That's my 3D printed radio video :)
I want to build some simple short range walkie talkies for my job. So your videos have helped me determine the components I’ll need.
This is a great channel and I say this with love: you should try editing out your inhale after every sentence
With more power and a amateur radio license you can use the AM transmitter and receiver you built to talk to people in other countries. With the right antenna and only 5 Walt you can talk to people far away.
My simple transmitter based on 6p3s tube. With main frequency generator on 6j8. For modulation i built simplest tube amplifier.... This thing can produce 7W of radio signal. It's Powerful for such construction.
Just in time i was looking on how to make these and you have gave an amazing explaination
At last! Project with which I can test old AM radios in pre-WWII era, or small AM transistors which are so simple they don't have a FM receiver!
Wow! Greatscott! You just play music with your function generator!!! [5:19]
Yes ;-)
@@greatscottlab yesssssssssss >:3
So cool
you can also use a crystal oscillator used for microprocessor clocks in the 80s to make a transmitter as it contains the entire oscillator.
also as more and more of the analog fm broadcasters go digital there will be the space opening up and the fcc may soon care less about the part 15 rules unless your transmitter should somehow cause a pacemaker to malfunction and cause a heart attack or completely drown out emergency responder communications.
fell in love with your boombox!!
Nice video. I really enjoyed this video. My suggestion is to use wegstr pcb milling machine to get a very nice circuit within less time.
Single Sideband is basically AM but much more simpler. You should try it sometime
Demodulating a SSB is complex. One has to regenerate the carrier using a carrier recovery circuit at the Rx to demodulate the SSB.
how electronoob and gratescott upload video in same time
Why do it easy when it can be done more complicated. A TL072 can be used as colpitts Oscillator and OP with variable amplification done by a JFET in the featback. The NF signal goes to the gate of the JFET. The SA602 or SA612 ist a mixer with build in oscillator. Both gives real AM without any detours.
Nice work again.. i have learn a lot in your videos.. please keep them coming
Love from India❤️
Nice, sounds like very old voice records. :)
I like this video.
Can you, please, show us how to make a better am transmitter;
Nice reciver btw.
Interesting.
I made an Am transmitter with the 555 a couple years ago. As I remember 600- 700 KHz is about the max you can set up the 555 to oscillate at. Mine did work. It had horrible harmonic issues and was all over the place. I had used an audio transformer to modulate the carrier.
Did it work, yep but..... not exactly clean at all and likely not worth the effort to filter....
nice Video, can you built a DAB+ Radio ? with an Arduino ?
I can put it on my to do list.
in xr2206 your voice sound similar to those 80s 90s morning news ..haha so nostalgic
I would think learning a bit more theory would be in order before posting a circuit. But that's not fun?
Straight and simple
Damn this was literally my final project for a lab class a week ago lol
Cool project and very informative for Electronics students
Went back in time to 1980s with my crystal radio receiver.....
Fantastic work, dude! Pretty interesting circuits indeed! 😃
Stay safe and creative there! 🖖😊
Thanks, you too!
I really enjoy watching your presentations, thank you
An AM powerstage would be an interesting video to feed the antenna. 😁
It would be really good to see the transmitter made from discrete components - go old school! Nothing more complex than a transistor...
Slightly off topic question
What do you call the leads with the springy hook ENDS?
@@pdemosllegaralos520subs2 test leads in general, clip leads or test clips more specifically, or hook clips when comparing to other clip leads.
I used an RC remote to make an FM transmitter.
Bhai aisa kaise kiya muje v btao
@@shriniwashasefirst select an empty fm channel for ex you choose 94.5mhz station in reciver press button of remote and with the help of screw driver rotate a black thing you will see in wrapped around coil. You will hear a around 1000hz tone.
find in pcb from where around 1000hz tone is generated. From there add audio input or audio can be input in series with battery.
Audio can be inputted from mobile phone using aux cable
@@Vivekstark68 kaha se late ho itna Dimag
@@shriniwashase khud se different thing bana ke dekhta rehta hu
I'm waiting for this
Im So Jelous Of Your Knowledge !
Awesome project man 👏👍.
Why don't you do an project with 24bit DAC with Raspberry Pi and with options like DRC control, Equaliser, ...
This will be interesting and useful DIY audio hobbyists like me.
Kindly consider this.
I tried to make this one, I used 12v as power supply and I tested t 3m away and when I am touching the output the signal increases and as I don't the signal disappears, why is that so? Can someone explain me?
Maybe you are an Antenna
Awesome, now to take it to the next level.
Hey Scott! Awesome video, but this AM waveform on 3:04 is not the best honestly. I get it, it's hand drawn, but it really got to a mix of AM and FM :)
As a tip for the next time, you could've drawn straight vertical lines with pencil to indicate where peaks of carrier are and should be in resulting signal :)
You after the video: *That was easy!*
_-Staples easy button_