Creating a Walkie-Talkie with generic 433MHz RF Modules?!
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- čas přidán 18. 04. 2020
- PCB+SMT assembly, from $2: jlcpcb.com/?ref=greatscott
Previous video: • Make your own Portable...
Previous Walkie-Talkie video: • Make your own very cru...
Andreas Spiess video: • #279 How to debug Ardu...
Class D Audio Amplifier video: • DIY Class D Audio Ampl...
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More project information (schematic, pictures, code.....) on instructables: www.instructables.com/id/DIY-...
Parts list (incomplete, see Instructables for more, affiliate links):
Aliexpress:
2x 433MHz Transmitter: s.click.aliexpress.com/e/_dZW...
2x 433MHz Receiver: s.click.aliexpress.com/e/_dYg...
2x TLC555 IC: s.click.aliexpress.com/e/_dTr...
2x MCP602 IC: s.click.aliexpress.com/e/_dTv...
2x TC4428 IC: s.click.aliexpress.com/e/_dUo...
1x Mic: s.click.aliexpress.com/e/_dSP...
1x 250k Trimmer: s.click.aliexpress.com/e/_dTF...
Resistors: s.click.aliexpress.com/e/_dTP...
Capacitors: s.click.aliexpress.com/e/_dU4...
s.click.aliexpress.com/e/_d7d...
2x Micro USB Breakout PCB: s.click.aliexpress.com/e/_dWa...
2x 1500uH Inductor: s.click.aliexpress.com/e/_d73...
2x Speaker: s.click.aliexpress.com/e/_d7x...
In this project I will show you how to use generic 433MHz RF modules from Ebay in order to create a functional Walkie-Talkie. That means we will compare different RF Modules, learn a bit about a class d amplifier and finally build the Walkie-Talkie. It can be powered by a normal powerbank for around 130 hours and features a range of around 15m. Let's get started!
Thanks to JLCPCB for sponsoring this video
Visit jlcpcb.com to get professional PCBs for low prices
Music:
2011 Lookalike by Bartlebeats - Věda a technologie
The "and I will see you next time" has been slowly getting more and more enthusiastic over the years... Lol
Eventyally he is going to explode
@@markusfpv1349 let's hope that's a long time away
Rusty Mustard It is... a common way to say goodbye
@@rustymustard7798 Occams razor my dude
i wilL SEE _YOU_ *_ALL_* *_N̸͍͕̍͐́̎̒͑E̶̖͕͎̝̣̻̯͇̦̠̩̯͓̼͇̿͌͌̄͆X̵̛̰̘͉̳̻͓͌̇͗͋͝Ṱ̷͚͈̂̄̄͌̇̈͋̅̓̔̍̓͌̂͘ ̷̛̖̌̉̾̌͗͌̀͆̍̐̌̕T̵̤̫͓̯̔̒̾̒̈́̀̓̉̾̚̕I̶̢̧̗̹̜͓͉̯͙͐͂́̿̂͠M̶͈͎͈̱͔͈̬͎͋͒͛͒̑̉̈̚͠͠͠È̶̠̳̾̄͌̒̋̏̿̉̕̕_*
Question, the module was able to send audio range analog signals. Why not directly send analog through? modulating the analog to digital would require a much larger bandwidth.
Because it can't. 3:04
It would be nice if he tries to do this again but all analog, using a FM radio receiver and transmitter.
hi electroboom
Hey electroboom, big fan!
If transmitter works with high and low threshold levels trying to send any analog signal this will be distorted to squarewave.
Greatscott!: _"as you can hear, it still sounds acceptable"_ 8:17
The speaker: *demonic sounds*
@FQD2N never knew a MOSFET could post a comment
Not the first one I've seen, @@not-pyroman. If you're been around for a while, you'll recognize a user with IRFZ44 username. That guy used to be popular in some videos. Don't see it anymore though, wondering what happened.
@@Asu01 too much current, he blew up
@@Asu01 i think I've seen that one once or twice
Edit: ice to I've. Fucking autocorrect
Bluey!
What i know that when you want to transmit an analog signal via a digtal transmmiter the first step is sampling the analog signal , and there is a condition to consider which is the sampling frequency must be as twice as the maximum frequency of analog signal , therefore if you picked a sampling frequency then you must make sure that the maximum frequency in the analog signal is half the sampling frequency, otherwise every frequency which higher than half the sampling frequency will be picked as noise.
Sorry for long comment.
I absolutely agree.
Nyquist frequency!
When the frequency of the signal is higher than half of sampling frequency it not generate noise, its aliasing wich is worst. And nyquist criteria of double of max frequency of the signal is just valid theoricaly for infinite signals. If you want good audio quality it just need to be at least 10 times.
Yes i agree, it named the Shannon-Hartley theorem for whom wants to elaborate.
Absolutely agreed. But for crying out loud this noisy approach as good as it may work for a D power amp seems pretty useless in this application. Wouldn't it be orders of magnitude easier and better to use good old FM. .. (in an analogue way of course)
8:34 I take it that you're not hearing the painful high pitched sound during the mike test... Oww, my ears
I'm still in hope of seeing you making one RF transmitter from scratch.
Honestly, even though he's from Germany, his English sounds better then most of the people in Holland (like me😁). It's clear, I can understand it, and he talks slow!! Great Job Scott!!! Keep up the good work!
I've noticed something, most people that don't have English as their first language speak it better than quite a lot of native speakers that I know (including myself)
I am intermediate english student, i dont understand native english speakers, because they talk to fast, but i clearly understand great scott
I'm not English nor German but i still can understand him while he speaks English or German. He can speak both fluently and clear
@@KingJellyfishII I come from China,My English listening is too bad,in order to know the content of video,I must see English subtitles,Unfortunately there are only German subtitle options,I wonder why app provides Germany options when I know that host is speaking English. I go on listening and find the pronunciation of host like German.😄
@@bofeng2700 The host is German, so he likely provided German subtitles for his local viewers.
Have been following your channel since long & have learned a lot.
Always heard your voice but really pleased to see your face, great work man keep it up :)
"You can hear that the music transmission was also successful" 7:45 I only hear beeping.
Nobody will ever accuse him of being an audiophile. I can get at least 800 feet of very high fidelity audio by modulating my bench signal generator.
Most electronics engineers consider waveforms as music ^^
I'm very impressed JLCpcb is still operating now. I bought 4 boards yesterday.
That moment when Great Scott posts and you get to it 30 seconds later...
Awesome!
I have read a bit through the comments. One person already suggested to use these moduls in their "analouge" mode. The transmitter is simmilar to one of these TTL oscillators. You simply can bridge the data pin to "+" from your supply, and series modulate it with a PNP or NPN Transistor. This will give you AM with FM. The FM Part is just narrowband FM, but on a selective receiver you´d need to use slope detection, but these receivers usually are "Super regenerative receiver(s)"
I´m mainly talking about the green circuit boards (the ones completely on the left side in your frequency test, that just could take 5KHz).
On the receiver there´s a two stage super regenerative receiver. One transistor works as RF preamplifier, to get the RF noise away from the antenna, whilst the other one is the actual receiver. On your modules, at least the RF preamp transistor is mounted - the modules I have, the receiver misses the transistor (probably were lower price due to this fact got them as a gift)
On the receiver board, the output from the super regenerative receiver goes to a lowpass filter hence it´s quench frequency (thats why you only can transmitt up to like 5KHz). The 8 pin SMD Chip - LM 358 - only forms the sine wave into a square wave.
You can "tap off" the signal from the receiver before the LM358 chip, and so you can make complete analouge audio transmission. All you need is a modulator + microphone amplifier on the transmitter side... and a small audio amplifier on the receiver side with "tapped in" audio pickup before the LM358.
Practically
- To get the transmitter to transmitt AM -
Bridge "Data" to "+ UB" and take a standard NPN Transistor. Use double supply voltage, and tap the transistor between
"-" of your transmitt module and ground. Now use a 1M Potentiometer, and a Multimeter. Connect the 1M Potentiometer between base and collector, and have it adjusted to "1M" at the start. Now decrease it´s value,
untill you reach about the half supply voltage on the module.
Via a 100nF capacitor and let´s say a 3,3k resistor (random values) you can now put Audio on base of the transmitter.
The audio would already be received from the receiver, but it would be extremly distorted because the LM358 converts the sine wave signal from the regenerative receiver to a square wave signal.
Take an amplified speaker, hook one pin up to ground from the receiver module (while the transmitter is on, try with a low volume level on your phone with my suggested values) and use a let´s say 10k + 10...100nF (whatever is in the parts box) between "audio in" from your speaker and the connectors around the LM358 - one connection will be "audio out" from the receiver. If you find it, you will hear your music over the speaker.
Later if you want to use that "concept" you might need to add a lowpass filter between your receiver module and an audio amplifier Chip, because some remains from the receiver´s quench frequency might be left, and block / inteffer with the audio chip (very quiet, could start motor boating if connected to the same battery).
For the transmitter you don´t need to use the full voltage. If you lower the voltage the "AM percentage" will increase, whilst the FM percentage will decrease, but "good" AM will cost a lot of TX power (like going down from 10 to 0,5mW)
Anyhow, since the receiver is a wideband super regenerative type, it won´t care about "that bit" narrowband FM, but
if you´d receive this on a more "proper" receiver, that has AM option, you´d need to use slope detection for it.
I´m talking about the green modules ... some other modules might use a more "fancy" "Superhet" receiver.
Regarding the 1M potentiometer... maybe a 250k might also work... I don´t know how these transmitters react
to overvoltage. TTL modules "can take some" but I´m sure it´s not good for them.
I´d appreciate it if you´d give this a try, but since my comment is just one of many... I´m not really expecting much
I like how much enthusiasm you put on your videos, keep up the good work! :)
You can transmit and recive analog signal (using the first pair TX/TX boards) if you bypass the comparator on the receiver, the 8 pin chip normally is a lm328 amplifier configurate in one half amplifier and the other half like comparator, this last one is what you need to bypass to get an audio signal
Best electronics & mad science channel ever!!!!! Keep coming amazing stuff Great Scott 👏👏👏
Great job, there's always room for improvement and i love that you're always trying to better your designs. keep up the good work.
Thanks, Scott. It's inspired me to making wireless subwoofer. I don't need very high bandwidth rf module because my sub only need maximum 500hz.
your videos are always outstanding Great Scott
Can't you use an OpAmp in a substract form to remover the unwanted fix frequency on the output? or the delay is too high?
The problem would be to line up the frequencies. If you don’t get it exactly right, you’d be adding instead. A low pass filter or band-stop filter would be better.
One of my favorite channels .... wow, great work, allways surprise me
Hey...finally "let's get started" has his face out of hidden. Great Scott!!! Your projects are awesome!!
Here's something else to consider:
The reason you may want to bring an Arduino back into the mix is to use it to create a form of buffer. The idea is that if you buffer the signal, even for say 100 transmissions, you can use that to avoid choppiness. Of course, the transmission would need to be slightly higher than the buffer size so it can catch up, which in turn in a poor man method, results in some dropout of single packets, but that would be my basic, noncomplicated approach.
Great video Scott! Great to see your troubleshooting process even if results not amazing
Your videos are very enjoyable. Thank you.
hey Scott! Been following you for a while and I have to say that seeing you in the videos definitely make them more interesting! Keep it up!
Really good work and fun watching.
Love your videos dude. Keep it up!
Great project! Thanks for a very informational video :)
Got to say that's pretty impressive for such cheap device! Thanks for sharing the idea! Stay safe!
Great video nice tests!
Great video. Seeing the failings and shortcomings prompts discussion and encourages people to get involved. I don't know how to fix the circuit, my first step would be to straighten the antennas, but other than that I wouldn't know.
Great video, keep up this good work!
7:16
You killed my ears :'(
8:35 killed mine :D
Great video, lot's of useful information for us "beginners." Keep up the good work!!
Great work as always ,, Great Scott..!!
I don’t suprise anymore. I was sure about walkie talkie and you have done with it! Thanks for the video.
i loved the old intro format too, but i love the new one too! you look good on camera
While studying electronics and communications engineering, they teach us that we only use a bandwidth of 4 Khz when it comes to voice/speech transmission so technically the first tx rx pair is actually decent enough for use in a walkie talkie! That 4 Khz even includes the guard band which results in a useable spectrum from 300 to 3400 Hz.
Few recommendations for improvements: try to use decoupling cap between pin 2 of the comp and pin 6 of the 555. Also you may use voltage divider and adjustable POT resistor to vary the level of the output from audio circuit - shift up and down. This may produce better PWM that improve on audio fidelity. Also you may use very weak pull down resistor on the Data in of the XMTR, if it is floating from the XMTR board module. If the XMTR board allows powering from higher voltage then you may try it for longer range, tinkering with the antenna and its impedance also may boost the communication range. Apparently the XMTR-RCVR pair modules are not designed to deal with those kinds of so called PWM wave forms, thus a conditioning circuits maybe needed as I described above. In Radio circuits, it is vital to insure impedance matching on input / output ports for both XMTR and RCVR circuits, not only on RF circuit (here you can not do anything about it, unless you tinker on the module board) but also the audio circuit.
From what I know, you should use the high frequncy TX signal as a carrier. Insert audio into it.
In the RX section, you must separate the carrier signal from the audio, then amplify the audio.
Just like FM TX or AM TX. On FM TX, you affect the carrier frequency range. In AM TX you affect the carrier amplitude.
I learned a lot from this channel
I love this video. I didn’t know you could generate a PWM signal via a triangular wave
awesome idea and implementation! thx for the vid!
Can you use the same circuit to make a wireless remote ie transfer digital key presses? And how high would the latency be?
I like the way you doing the show ☺️
Would love to see an episode dedicated to tube amplifiers. Trying to make one myself (I've found some old soviet 6n3p-ev tubes) and can't get my head around calculating the cathode and anode resistors.
Finally! 'been waiting for this video for so long. I am always to lazy, to order the stuff i develop, so i firstly watch other people doing it :_D
Great videos by the way!
Thanks :-)
You are great you inspires people .
This was very thought provoking
Is it just me or "hh" inhaling/gasping sound increased at the start of each voice audio clip?
Once you hear it, you cant un-hear it. It happens in every video :(
@@emyalfaro The problem is that if he removed it then everyone would notice that you can never hear his breath.
Man, I do not recall seing your face before. Is like a new age for Scott channel. Good to you, brother. Keep the excel videos.
Hey your arduino walkie talkie worked . I tried andreas spiess solution, placed a potentiometer instead of resistor. After few tries, it worked like a charm, covered distance of probably 100 meters
I was remembering my master's time by watching your video. Anyway, Gr8 video and I am going to recommend your channel to our students. 🙏🙏
Very good tutorial !
Great video, thanks! I've a question I think you did not cover, maybe I missed something. But in the final product, it seems like you've got bidirectional communication between the walkies; how do you manage that aspect? Since the transmission is raw data, isn't there any feedback?
Not great, not terrible
that's what they said in Chernobyl when the radiation was 3.6 röntgen ( bud was 15000)
It was "Not great, not terrible" if I recall correctly.
@@kvlpnd
you're right
But then again, Chernobyl is a "tourist attraction". I have doubts this 433 walkie talkie will be a tourist attraction.
Very good project
Apparently as your intro starts my mind subconsciously starts the JLC PCB promotion 🤣🤣🤣
you are really amazing i love how you explain each detail
i'm student and this video helped me alot with my project 🤩🤩
A good basis to start from. Thanks for this.
Now that's a great episode we wanted....
You are FANTASTIC....
Best regards from Portugal
Excellent video keep it up
What do you think about sending the audio with packets? You start recording signal when i reaches threshould level. When audio level goes back to low - you compress signal in some way. Then send it as digital information. Yes there will be slight delay, but quality should be much better.
I hv sm fr module ( 1:00 not that one ) , but i wanna use it to make cheap rf tool for me
I wanna make RF frequency analyser with serial port and 2nd portable display interface .
But i don't know arduino programming
I wish you make video on it.
i will be very thankful to you for helping me on my humble request
I've just builded my own automatic greenhouse based on the Arduino with Solarpower, Sensors, Waterpump and vetilation a few years ago.
The only missing Thing in my Setup is the LoRa-Wan that i now had to have 😉.
Great Scott 👍😁
Was waiting for this video...love from india👍🏻
Well, it needs 2 pairs of Transmitter & receiver module?
I cant tell if the high pitched noises at 5:20 are the music or a reference
if you want a decent range on those, you can get it by building yourself a dipole antenna to replace the monopole. I've even built a crude yagi antenna for use with modules like this, just with one guide element and one reflector element. there's some calculators around that can make it easier for people not so comfortable with antenna design to build their own antennas.
fortunately, these are relatively low frequencies, so you can be a bit sloppy with your antenna construction and still get decent results.
Sir,should you have any idea to make a Brushed Electronic Speed controller (BESC) to drive 12v dc motors
hey Scott, do you recommend the rigol ds1102E oscilloscope for a first scope?
Quick question! Is there any possible way you can reverse the order of videos on your Electronics Basics playlist? If Someone were to view the playlist and let it play, it would start at 44, then 43, 42, down to 1. I think the order can be reversed to start at #1 thru to #44. If it's possible, can you reverse it please? Thank you :)
Id like to see some follow up videos from you going into more detail of these projects. I like seeing how I can make crude versions of things but why not buy a few commercial devices, take them apart and see how they do it and try to add some of the stuff to these? What if there were cheap chips available on eBay that would actually work better but didn't have a breakout board?
Can I use these RC modules to send a basic On/Off signal like on a remote ?
Can you use the rf module to transmit usb data so we can mod wired usb keyboard to be wireless?
Fun stuff, thanks!
oh I have same modules as you have used but they never ran with HT12E and D ICs, and dont think that has hight frequency of 18k Hz, and second thing is that what about usinf FM?
Instead of audio, would it be possible to do very basic video transfer. Reason I ask I have a project with a PIC microcontroller and we are using it to generate a simple display like a square via VGA. It would be awesome to test with wirelessly.
How does microphone make difference between different frequences of sound?
Is it possible to control volume of a speaker that only has analogue potentiometer volume control with a remote and arduino? I know you did this with a digital volume controlled speaker system but is it also possible with an analogue volume controlled one? Thanks in advance :)
How can I make the range clear to 15 miles or is it not possible? I need it for emergency to communicate with family in my bug out bag. Thank you!
You can’t do this. And if you could, it would be highly illegal (Imagine disturbing some important infrastructure with your signal) Depending on the country you are living in, I would suggest looking at CB radio (en.m.wikipedia.org/wiki/Citizens_band_radio).
thes transmitter modules actually can transmit audio, the data pin on the receiver has a comparator. therefore for digital signals, on the 7th pin on the chip if i remember right, theres the analog signal not passed through a comparator. just attach a wire to the pin.
@GreatScott! - instead of using a trim-pot variable resistor for your audio input, make a low pass R-C filter from the output of the 555 to ground, which will give you a DC level, at 50% of the triangle wave amplitude, use this voltage and connect to the lower end of a trim pot, connect the wiper to the op-amp input and connect the 'top' of the trim pot (which is now your volume control) to the audio source via a DC blocking capacitor. This arrangement will 'auto-level' so you always have 50% above and below.
Also, on your output amp (TC4423 I think?) add a DC blocking cap to the speaker, those gate drive IC's don't like static DC current and you'll overheat the top of the totem-pole.
Hey GreatScott! How about an ultra accurate diy voltmeter/ammeter/ohmmeter?
To get rid of the 5kHz frequency, perhaps a band pass filter can be used... You can cascade the LPF with the 41kHz cutoff freq with a high pass filter > 10kHz or so
I was thinking that a band-stop filter could probably do the job. At the very least, you could use a series LC circuit to short out the 5KHz signal, though you could probably do better with a Butterworth or Chebyshev filter.
This is so great oh my god. I was literally just thinking of what to do with these. I bought quite a few of them thinking wireless would be usefull.
I definitely learnt something new
I love your videos Man !!!!
See u next time !!!!
It turned out it's not only me who gets green micro USB expansion modules and solder it directly using the pin headers to my circuit !
GreatScott!! 👍👍💯
Hearing you breathing after everything you say is blowing up my mind 😂😂.
I love your videos
Where do you get you fine point color pens from and what kinda of paper do you use?
As I understand, the TC4428 is the amplifier, right? Can I replace it by another class D amplifier since it is hard to get one in my country ?
i remember the 1st video, you wanted it for riding your motorbikes with your friends.. i know you will come back to this one until you crack it because of why you want them.. cant wait to see you crack it.. : )
Can you explain how this transmiter works ?
It seems that everyone has all of their components sorted so neatly. Do you have a link to those bins that you use?
just search for tool drawers on amazon
Hi, can you make a video on how to convert a microfone (with the audio jack) in to a wireless one? Possibly very small and with very low latency. For example converting a lavarlier wired microphone into a wirelles one (you know how much they cost...)
I ran some tests on NRf24L01 with different range, power mode and data rate but the data I transmitted was not completely recieved even when the transmitter and receiver were 1 feet apart.
I also used my bluetooth speaker in NRf24L01 walkie talkie, the result was that it worked perfectly some times but it wouldn't work at all and created a tik tik sound.
Sir please help me
I made a 4 channel transmitter and receiver circuit using 433Mhz rf module with HT12E and HT12D ic. But when I provided both the reciver and transmitter circuit same voltage 5v then communication didn't work that is data was not received. But when I powered the transmitter circuit with low voltage than receiver circuit around 2.5 v then communication between the two worked and data is successfully received that is led on the receiver side turned on. Why is this happening?