i think this video is the best DIY about radio i have ever seen, it takes you step by step and explain why those design choices were made, and how to test what you did, while most of the other designs are like blind design without explanation not testing iterative design is best way to learn
Well explained. I would generally be cautious though about transmitting square waves as the scope for spurious harmonics, especially without a low pass filter in circuit, is high. And yes, 1 or 1.6MHz transmissions, without a broadcasting licence, are illegal in most countries.
I do want to get my radio license but how whould the government or related branches know it's me doing this and it's ok? I will make this after I get my license but whould me doing this get people angry Even if I have a license for transmission?
@@kylewatson952 He's talking about transmission in so many YARDS of range, so the amount of power here is tiny, maybe 50-200mW, which will likely get swamped the first time someone with a '68 Cuda running copper core sparkplug wires drives by. :D If you keep your transmission power under 200mW, and avoid sending profanity over the airwaves, try to stay out of active transmission space, and are only playing around 10-20 minutes at a time, nobody will likely notice. As for locating spurious radio emanations, google search the term "radio fox hunts" or ARDF. There are also plenty of public radio space bands to play with, called the ISM bands where you've got all sorts of consumer radio products operating, and oddball modulation schemes like LORA-wan devices, which is low power, low bandwidth, infrequent transmission for whatever gadgets you care to built. Say a bunch of remote weather or telemetry systems that can run off one 18650 battery for a couple of months.
When I was a child, built an AM tx using a 2sa15 germanium transistor, 1 ferrite rod, 2 100pf caps and 3 resistors. it ran of 2 dry cells. could be modulated with audio. It worked and was stable. simple colpitts oscillator. tuned by moving the ferrite rod. no external antenna . sufficient signal for use in a small house.
At 11:13, this capacitance you describe from your hand moving around the antenna is the main theory behind the electronic musical instrument, the Theremin
To be clear, broadcast medium wave antennas are usually hundreds of feet high, but of course a conspicuous 'pirate' antenna setup would be an instant location giveaway. This is a nice demo for experimenters, showing that something can be got out of simple circuit and a tiny antenna. I think an opened out roll of cooking foil, might have been less lossy and would have made a slightly better ground reflector than a vertical ground rod.
The 555 that generates 1 kHz has an error. There is a wire missing that is supposed to connect pins 2 and 6. It won't work without this. The Q4, Q5, Q6 outputs seem to be out of bounds. The R17 biases Q5 fully on. If the ground wire touched the antenna, the excessive current through Q5 would burn it out. So there should be a DC blocking capacitor, like a .1 uF ceramic disk, in series with L2, to stop the DC. But the output has too many harmonics. Much of the RF is in the harmonics of the fundamental frequency. They should be removed by a 1.7 MHz low pass PI filter on the output. Without it, there will be harmonics that may be interfering with higher frequencies. The ground wire is missing in the schematic. Thanks for the video.
Thank you so much for this video. Not only did you explain the project well, you made it look doable with the information provided. I've never done anything with RF, but this video just changed that. Time to go build!
After watching several of your videos, I have to say they are some of the best that I’ve seen covering anything remotely more complicated than a “hello world” Arduino sketch. I’ve studied plenty of concepts in college but they always lack in one way or another. You cover the system, the circuit design, and include equations as a bonus! All while keeping the DIY spirit… I’ll gladly listen to the static on your voiceovers for that!😂
Ich habe den Telefunken Detektor im Original.Die Abstimmspule hat 2 Schleifer.💖🇩🇪🤐Einmal die Anpassung der Antenne,das andere die Abstimmung.Alles ohne Drehkondensator.Somit arbeitet sie als galvanischer Transformator selektiver.
Good work! I would improve the schematic 13:28 - between an emitter of Q3 and ground place 10 Ohm resistor (maybe with a capacitor 47nF). R10 change to 10kOm instead of R11 I would place wideband RF transformer: twisted five wires on a NiZn ferrite core (maybe with a small air gap). Three wires (I mean windings) connects in series as a load of Q3, four and five wire connects to an input of the push-pull cascade with the 2N2222 transistor. The bias circuit for 2N2222 contains : a silicon diode (1n4148) with a 1-2KOm resistor to positive rail. Both transistors loads on a wideband output push-pull transformer.Both emitters of 2N2222 connected together and to the ground in series of a 10-20Ohm resistor. The wideband transformer allows matching high impedance of Q3 with low input impedance push-pull output cascade (because a Miller effect in BJT) and increases power amplification.
Nice! Future projects could be, naturally, voice modulation but also something that would turn on remotely using a specific sequence of pulses like a digital 'key' to trigger something at a distance like a light or something else, digital data like '1', '2', '3' etc., something that remains on as long as it receives the signal, and other fun applications for the receiver.
@@metamud8686yeah and it seems that kind of technology has been lost in the dump as there is no information anywhere on how to make a multi channel transmitter and receiver from scratch without using the pre built RF modules and IC’s. What a shame 😢
Amplitude Modulation (transmission or reception) is relatively basic as far as radio communication is concerned. I remember in my ET-A School years ago we called Frequency Modulation "Fewking Magic". That said, if/WHEN the SHTF it will be folks that have knowledge like this who knit society back into a (semi)cohesive whole again!
Pretty sure the push-pull amplifier has the npn and pnp swapped round (normally the emitters are connected together, and form the output). Also the 555 usually has pin 2 and 6 connected together in the configuration shown.
At 1 Mhz the antenna would be an optimum radiator as a long horizontal wire , 20 foot off the ground , that your garden permits ! ( the full wavelength is approx 300 metres / yards !! ) , so a longer antenna is MUCH easier to match at this low frequency ... shorter antennas work best for stuff like CB radio ( 27 Mhz ) ... note : however a super efficient antenna might cause interference in the next state ! ( probably not a good idea ? ? ) .....
There were no radios in the late 1800's. Try the early 1900's instead. And of course the first working transistor wasn't made until 1948. That was a Germanium point contact transistor, which is quite large, and still exists as a museum exhibit. Junction transistors became available in the late 1950's, and Silicon junction transistors were later still.
Cool beans. I've assembled several over time & the last time I just used the 555 timer chip since you can get it to oscillate in the AM broadcast frequency interval. In a sense it sucks because the square wave it produces comes with plenty of harmonics, but I just wanted to play with the idea and indeed I did get licensed as kc2wvb roughly 12 yeats ago and even updated it in 2011.
Why did you clipped the signal? It had a reason or it was a side effect of the amplifying? Also I noticed that the signal before the amplifier/clipping has 9.52V, and then it has 9.68V. It didn't changed that much. This step seems not necessary to me. Can you elaborate more?
It would be interesting to know how much difference the capacitance hat made to the capacitive reactance, radiation resistance and (hence) the transmitted power.
you have to broadcast the infamous number station call sign melody "The Lincolnshire Poacher". The best radio value I know is a Baofeng.............$30 has 5km of range.
hm, might be cool to modify it so it fits into that 160 meter slice of ham, seems pretty close already, so probably pretty simple to get it up to 1.8-ish mhz suitable for CW
lol qrp on the commercial AM broadcast band, would be interesting to try sending code at 1700 KHZ to see what you get in return lol. but like you said, you have to be a bit careful not to qrm over top of another station that might be occupying the frequency you wish to use.
Thank you for that video. Very educational. I used to make those when I was a kid but it was always somebody else's schematic diagram and I learned very little. I mean I built it, without really knowing what I was building. I think I'm going to go back and build another one, even though my wife says I'm too old for this.
@@HyperspacePirate See th-cam.com/video/y8te4Mir_BY/w-d-xo.html I'm still experimenting with an antenna matching network, so the range is limited. 300 feet of 10awg would do the trick, but I can't really justify that expense, nor do I have a broadcast tower in my yard. Ha ha. The coil set up you're using is similar to a crystal radio antenna I built a while back. Have you tried adding a 300p variable capacitor to it?
@@andrewferg8737 that's an impressive setup. I'll need to look at it a couple times to fully understand what's happening, but your approach of inductively coupling your antenna is one i want to try with my next transmitter. I recently got a hold of several ~50-300 pF 3 and 4-gang variable capacitors from some old aircraft radios, so I want to try them out in a future build for tuning
@@HyperspacePirate "inductively coupling your antenna" The output transformer of the push-pull amplifier is not technically part of the antenna, although electrically it certainly is. Normally I would put a pi filter between the antenna and that transformer and tune it for maximum output. This works great at higher frequencies like the FM band. I tried it with the 3W base AM transmitter and it works somewhat, but I haven't had any luck at higher power in that frequency range. The 30ft antenna wire seems to dominate the output. I will try a shorter antenna with a large air coil & varicap next.
Awesome video, just found one little mistake in the clipping amplifier schematic, the PNP transistor is placed wrong with the emmitter connected to GND
Wouldn't it be possible to make an oscillator with TTL or CMOS chips for the carrier frequency instead of going to the trouble of making a Colpitts oscillator and then an amplifier ?
iam searching to buy an antenna for this project! But most of them are over 400 MHz. What frequency, the antenna should have in order for this project to work out?
Make a receiver video, please 🙏🏾 I have had a working transmitter for a while and can pick up signals with a purchased am radio but I can't seem to make the receiver from scratch
What do you have to study to be able to keep up with this video? This seems like an excellent step by step explanation but I don't know nearly enough math to know whats going on.
Thank you so much for this! The one question I have is: Why did you go to the trouble of turning the approximate 1mhz sine wave you got out of the Colpitts oscillator into a square wave? I thought that it would have been cleaner and easier to just use the sine wave and maybe filter it a bit to make it look nicer, considering that a sine wave has so many harmonics and all.
I'm pretty inexperienced with RF, so at the time i thought a square wave would be cleaner. After looking at the output of this transmitter on a spectrum analyzer and seeing all the harmonics, it was clear that that's not the case
Oh dear. It could have been so much better. (It could have been an actual AM transmitter).Why create a square wave? That will simply waste power and cause a lot of interference. You've got a sine wave, why not use it? That's what the transmitted signal should be anyway. The modulation method might work, but will need alteration to actually allow linear operation with audio. Better to use series modulation of some sort. It's a nice start for experiemntation, but will need some changes if you want to actually use it as, for example, a pantry transmitter or even a broadcast set.
hi iam very curious, can it produces magnetorestrictive effect if ferrite core+permanent magnet was present in coil arrangement? if you read about ultrasound generator there are 2 type : piezo(ceramic) n magnetorestrictive(coil) based, both of them commonly work around 30 - 40 khz ranges, yours was 1000 khz!
Could you give a link to the site you found that antenna capacitance calculator ? I can't find it and I want to be able to make a good impedance match to get the most out of this circuit.
probably why the range is so bad is because the only transmitter schematics you can get is for low power transmitters in the micro watt range. the fcc and arrl very carefully guards the schematics for transmitters for anything higher than a small fraction of a watt so if you want even to make 5 watt transmitter you need an fcc license and be a radio engineer.
HSP - I have a Question - and I Know you have the ability to answer. I've Subscribed to help your efforts and here's my question and I'm asking for your time yes that's what I'm doing What would happen if I built a '2 x tower Tesla Coil' - only it has 110 pancake coils making up both towers so that's 2 towers with 110 pancake coils as opposed to a single wire aircoil these have 220 Pancake Air Coils all in 2 stacks - you got that so far? Now I'm going to be weird and supply all 220 pancake aircoils with 3 different wire supplies and have all 660 wiring circuits all connected to a Really Big Transformer and balance it all off with some capacitors. The Pancake air Coil circuits are going to be 110v at 50 cycles. Absolutely Not Wired like a Tesla Coil but apart from what is said that's what I want. Now I'm going to hit those towers with a very powerful 8 Hertz and hold my 8 Herts for over 4 hours. A. What's going to happen to the 220 pancake coils and structures holding them? B. What's going to happen to the transformer and all the capacitors? C. In your own words please describe the environment.
Why add all the amplifying components if the maximum current draw from the antenna is only a few tens of milliamps? Yea sure you impedance matched it but the Q factor of that is so low that your not gonna be pulling hardly anything from your source. You could probably get away with attaching your antenna directly to the output of your colpitts.
Im willing to bet you had FCC vehicles going around your general area for a day or two after this experiment, trying to find that source of interference.
i mean if there’s a way to transmit radio signals much like how a spark gap transmitter works but without the use of a power source or batteries. I’m no expert on this field, but apparently such a device is possible.
@@joemawmaw8609 Only example of that I'm aware of is a steam turbine with a generator used to generate AC at the transmitting frequency en.wikipedia.org/wiki/Grimeton_Radio_Station
@@HyperspacePirate I sent you a link to schematics for such a device that may exist here but TH-cam kept removing my comment for seemingly no reason. I sent you an email with the link if you’re interested, would love to know what you think
YOUR EXPLANATION of an AM CARRIER is COMPLETELY INCORRECT. Go do some research on single sideband, which is one sideband of AN AM SIGNAL, having removed the opposite SIDEBAND, as well as SUPRESSING THE CARRIER. There is no "envelope," and AM modulation does not affect the carrier as you claim. SIDEBANDS That is the key word
@@DavidEsp1 Yeah it can be confusing between dB / dBw / dBm. To add to the confusion, in audio, dB are usually 20*log10(X) instead of radio where its 10*log10(X)
@@HyperspacePirate Yes that one already gotcha-d me. They’re not really different in meaning, both are power, it’s just that in audio-land it’s amplitude (traditionally voltage, now digital) that gets measured and displayed as waveforms (in DAWs and NLEs). So since power is voltage squared (and in log-world squaring becomes doubling)...
@@HyperspacePirate Just don’t get me started on dB differences for mono and stereo ! Loudness levels for mono generally need to be halved (-3 dB) as compared to those for stereo. Based not on simple maths but a messy compromise - in objective reality depends mainly on how identical the sounds on each channel are. I (and a pro I sought advice from) were “gotcha’d” (in my case badly) by that one (I guess no mono final mixes loudnesses recently experienced in that pro‘s broadcast world).
1. Put a Vacuum sphere on the top load. Better Signal 2. Just use a pwm to pulse the 1mF coil at 9ms better signal and POWER 3. Most importantly, the ground rod needs to be In between the Inductor and capacitor. All together better Geometry Less parts and materials.
Привет друзья ищу команду энтузиастов которую тоже хотят полететь в космос и построить ракету для начала если есть желающие и отважные люди пишите мне обсудим этот момент
i think this video is the best DIY about radio i have ever seen, it takes you step by step and explain why those design choices were made, and how to test what you did, while most of the other designs are like blind design without explanation not testing
iterative design is best way to learn
Concordo.
Well explained. I would generally be cautious though about transmitting square waves as the scope for spurious harmonics, especially without a low pass filter in circuit, is high. And yes, 1 or 1.6MHz transmissions, without a broadcasting licence, are illegal in most countries.
Is it better to just transmit sine waves, and skip the wave “clipping” phase of this project that creates the square wave?
Can't be a Hyperspacd Pirate if you're a Hamm
I do want to get my radio license but how whould the government or related branches know it's me doing this and it's ok? I will make this after I get my license but whould me doing this get people angry Even if I have a license for transmission?
@@kylewatson952 He's talking about transmission in so many YARDS of range, so the amount of power here is tiny, maybe 50-200mW, which will likely get swamped the first time someone with a '68 Cuda running copper core sparkplug wires drives by. :D If you keep your transmission power under 200mW, and avoid sending profanity over the airwaves, try to stay out of active transmission space, and are only playing around 10-20 minutes at a time, nobody will likely notice. As for locating spurious radio emanations, google search the term "radio fox hunts" or ARDF. There are also plenty of public radio space bands to play with, called the ISM bands where you've got all sorts of consumer radio products operating, and oddball modulation schemes like LORA-wan devices, which is low power, low bandwidth, infrequent transmission for whatever gadgets you care to built. Say a bunch of remote weather or telemetry systems that can run off one 18650 battery for a couple of months.
Ya, square waves have infinite harmonics.
Takes me way back to electronics classes in college.
When you said 555, I got chills.
When I was a child, built an AM tx using a 2sa15 germanium transistor, 1 ferrite rod, 2 100pf caps and 3 resistors. it ran of 2 dry cells. could be modulated with audio. It worked and was stable. simple colpitts oscillator. tuned by moving the ferrite rod. no external antenna . sufficient signal for use in a small house.
At 11:13, this capacitance you describe from your hand moving around the antenna is the main theory behind the electronic musical instrument, the Theremin
To be clear, broadcast medium wave antennas are usually hundreds of feet high, but of course a conspicuous 'pirate' antenna setup would be an instant location giveaway. This is a nice demo for experimenters, showing that something can be got out of simple circuit and a tiny antenna. I think an opened out roll of cooking foil, might have been less lossy and would have made a slightly better ground reflector than a vertical ground rod.
The 555 that generates 1 kHz has an error. There is a wire missing that is supposed to connect pins 2 and 6. It won't work without this.
The Q4, Q5, Q6 outputs seem to be out of bounds. The R17 biases Q5 fully on. If the ground wire touched the antenna, the excessive current through Q5 would burn it out. So there should be a DC blocking capacitor, like a .1 uF ceramic disk, in series with L2, to stop the DC.
But the output has too many harmonics. Much of the RF is in the harmonics of the fundamental frequency. They should be removed by a 1.7 MHz low pass PI filter on the output. Without it, there will be harmonics that may be interfering with higher frequencies.
The ground wire is missing in the schematic.
Thanks for the video.
Thank you so much for this video. Not only did you explain the project well, you made it look doable with the information provided. I've never done anything with RF, but this video just changed that. Time to go build!
new unlock: the ire of the FCC
@@the_7th_sun fox hole hunt
After watching several of your videos, I have to say they are some of the best that I’ve seen covering anything remotely more complicated than a “hello world” Arduino sketch. I’ve studied plenty of concepts in college but they always lack in one way or another. You cover the system, the circuit design, and include equations as a bonus! All while keeping the DIY spirit… I’ll gladly listen to the static on your voiceovers for that!😂
Ich habe den Telefunken Detektor im Original.Die Abstimmspule hat 2 Schleifer.💖🇩🇪🤐Einmal die Anpassung der Antenne,das andere die Abstimmung.Alles ohne Drehkondensator.Somit arbeitet sie als galvanischer Transformator selektiver.
Your PNP transistor emitter usually connected to +Vin (Vcc)👽 3:42
Good work! I would improve the schematic 13:28 - between an emitter of Q3 and ground place 10 Ohm resistor (maybe with a capacitor 47nF). R10 change to 10kOm instead of R11 I would place wideband RF transformer: twisted five wires on a NiZn ferrite core (maybe with a small air gap). Three wires (I mean windings) connects in series as a load of Q3, four and five wire connects to an input of the push-pull cascade with the 2N2222 transistor. The bias circuit for 2N2222 contains : a silicon diode (1n4148) with a 1-2KOm resistor to positive rail. Both transistors loads on a wideband output push-pull transformer.Both emitters of 2N2222 connected together and to the ground in series of a 10-20Ohm resistor. The wideband transformer allows matching high impedance of Q3 with low input impedance push-pull output cascade (because a Miller effect in BJT) and increases power amplification.
11:38 Radio by day... theremin by night. Love it.
Nice! Future projects could be, naturally, voice modulation but also something that would turn on remotely using a specific sequence of pulses like a digital 'key' to trigger something at a distance like a light or something else, digital data like '1', '2', '3' etc., something that remains on as long as it receives the signal, and other fun applications for the receiver.
Welcome back to history, you're almost at the point of reinventing Morse code 🙂
@@metamud8686yeah and it seems that kind of technology has been lost in the dump as there is no information anywhere on how to make a multi channel transmitter and receiver from scratch without using the pre built RF modules and IC’s. What a shame 😢
Amplitude Modulation (transmission or reception) is relatively basic as far as radio communication is concerned. I remember in my ET-A School years ago we called Frequency Modulation "Fewking Magic". That said, if/WHEN the SHTF it will be folks that have knowledge like this who knit society back into a (semi)cohesive whole again!
Pretty sure the push-pull amplifier has the npn and pnp swapped round (normally the emitters are connected together, and form the output). Also the 555 usually has pin 2 and 6 connected together in the configuration shown.
I've always been wanting to build one myself! Now I can, thanks to you! Thanks for showing the way😄
It took me a long time to learn enough about electronics to make a radio work so I'm glad i could help someone else do it
@@HyperspacePirate thank you very much for inspiring the likes of me. Now I get to work again on my fave hobby😄
@@HyperspacePirate how long did you have to learn to actually build radio and understand it? and how did you learn?
At 1 Mhz the antenna would be an optimum radiator as a long horizontal wire , 20 foot off the ground , that your garden permits ! ( the full wavelength is approx 300 metres / yards !! ) , so a longer antenna is MUCH easier to match at this low frequency ... shorter antennas work best for stuff like CB radio ( 27 Mhz ) ... note : however a super efficient antenna might cause interference in the next state ! ( probably not a good idea ? ? ) .....
There were no radios in the late 1800's. Try the early 1900's instead.
And of course the first working transistor wasn't made until 1948. That was a Germanium point contact transistor, which is quite large, and still exists as a museum exhibit. Junction transistors became available in the late 1950's, and Silicon junction transistors were later still.
Cool beans.
I've assembled several over time & the last time I just used the 555 timer chip since you can get it to oscillate in the AM broadcast frequency interval. In a sense it sucks because the square wave it produces comes with plenty of harmonics, but I just wanted to play with the idea and indeed I did get licensed as kc2wvb roughly 12 yeats ago and even updated it in 2011.
Now the Americans should start using mouse farts as the unit of measurement for the power of radio waves.
Time to talk to aliens
এসওএস
(His neighbor trying to listen to his AM radio church program) "What the heck is that noise!!!"
lol
How do you know ?
It was a joke lol @@tonywright8294
It's satan, jamming the emanations of god.
Why did you clipped the signal? It had a reason or it was a side effect of the amplifying? Also I noticed that the signal before the amplifier/clipping has 9.52V, and then it has 9.68V. It didn't changed that much. This step seems not necessary to me. Can you elaborate more?
It would be interesting to know how much difference the capacitance hat made to the capacitive reactance, radiation resistance and (hence) the transmitted power.
you have to broadcast the infamous number station call sign melody "The Lincolnshire Poacher". The best radio value I know is a Baofeng.............$30 has 5km of range.
14:12 … at 1.6MHz you were so close! “160 Meters” band, 1.8-2.0MHz is Amateur Radio. Specifically, 1.800-1.820MHz is for Morse Code transmissions. 😊
it was 1.03MHz not 1.6MHz
Where are the side bands. That's what's really going on. It's really neatly done, good on ya m8. Brought back memories from the distant past. 🙂
Parece um transmissor com bobina de ruhmkorff.
Gosto dessas coisas.
Amazing Video as always
Since you are feeding a 1 MHz square (-like) wave into your antenna you have a plenty of output at 3, 5, 7... Mhz as well.
hm, might be cool to modify it so it fits into that 160 meter slice of ham, seems pretty close already, so probably pretty simple to get it up to 1.8-ish mhz suitable for CW
This sounds like how Marconi started but I have to question the transmition of Photons at 0:46....Photons?, Light?
Very informative, thanks for sharing video, Subscribed
Your PNP Transistor is reversed at 4:14.
Yeah i noticed that in his videos
Maybe this is his style
This remind me of Chinese circuits when they try to protect there knowhow
Great build. Keep up the good work.
Well explained! Can it be run on twelve volts as well?
could get more current gain on your output pair using a darlington configuration
lol qrp on the commercial AM broadcast band, would be interesting to try sending code at 1700 KHZ to see what you get in return lol. but like you said, you have to be a bit careful not to qrm over top of another station that might be occupying the frequency you wish to use.
You should build a amplifier for the transmitter signal
Thank you for that video. Very educational. I used to make those when I was a kid but it was always somebody else's schematic diagram and I learned very little. I mean I built it, without really knowing what I was building. I think I'm going to go back and build another one, even though my wife says I'm too old for this.
0:01 calling for artillery support ;)
🏆🏆🏆
very Best effort, thanks for sharing.
11:46 a little disappointed to not see a fancy 🎩, but I'll let it slide for this time
hand inductance . its about antenna and ground.
Nice job. Have you tried using transformers for the push-pull amp? They should increase your output considerably.
I haven't yet, but it's high on my to-do list for my next radio project.
@@HyperspacePirate See th-cam.com/video/y8te4Mir_BY/w-d-xo.html I'm still experimenting with an antenna matching network, so the range is limited. 300 feet of 10awg would do the trick, but I can't really justify that expense, nor do I have a broadcast tower in my yard. Ha ha. The coil set up you're using is similar to a crystal radio antenna I built a while back. Have you tried adding a 300p variable capacitor to it?
@@andrewferg8737 that's an impressive setup. I'll need to look at it a couple times to fully understand what's happening, but your approach of inductively coupling your antenna is one i want to try with my next transmitter. I recently got a hold of several ~50-300 pF 3 and 4-gang variable capacitors from some old aircraft radios, so I want to try them out in a future build for tuning
@@HyperspacePirate "inductively coupling your antenna"
The output transformer of the push-pull amplifier is not technically part of the antenna, although electrically it certainly is.
Normally I would put a pi filter between the antenna and that transformer and tune it for maximum output. This works great at higher frequencies like the FM band. I tried it with the 3W base AM transmitter and it works somewhat, but I haven't had any luck at higher power in that frequency range. The 30ft antenna wire seems to dominate the output. I will try a shorter antenna with a large air coil & varicap next.
Please make video about fm transmitter and receiver
Awesome video, just found one little mistake in the clipping amplifier schematic, the PNP transistor is placed wrong with the emmitter connected to GND
İyi calismandan tebrikler peki gönderdiği mesafeye göre enerji de artarmi frekans değiştikçe enefji de artarmi
i like to shift the carrier by 90degree and mix two IF and the carrier together
Wouldn't it be easier to pick a too large inductor for impedance matching and add a variable capacitor in series?
Wouldn't it be possible to make an oscillator with TTL or CMOS chips for the carrier frequency instead of going to the trouble of making a Colpitts oscillator and then an amplifier ?
Any chance of getting the STL/STEP files for the winder and the radio fixture itself? I want to build this.
the exact frequncy = 72,948.5 means around 73 Kh
iam searching to buy an antenna for this project! But most of them are over 400 MHz. What frequency, the antenna should have in order for this project to work out?
Impedance matching is a nightmare
Make a receiver video, please 🙏🏾
I have had a working transmitter for a while and can pick up signals with a purchased am radio but I can't seem to make the receiver from scratch
Oh look, a Thermin !
;)
Your CW is QLF (Are you sending with your LEFT FOOT?)
Why not use a crystal oscillator?
Picoferrets and millihenrys lol
..its prolly boring for you but a fancy crystal radio build would be appreciated
So, why the square wave output? That would generate a bunch of harmonics and waste energy while creating wideband noise?
hätte gerne eine bauanleiung bitte
What do you have to study to be able to keep up with this video? This seems like an excellent step by step explanation but I don't know nearly enough math to know whats going on.
Thank you so much for this! The one question I have is: Why did you go to the trouble of turning the approximate 1mhz sine wave you got out of the Colpitts oscillator into a square wave? I thought that it would have been cleaner and easier to just use the sine wave and maybe filter it a bit to make it look nicer, considering that a sine wave has so many harmonics and all.
I'm pretty inexperienced with RF, so at the time i thought a square wave would be cleaner. After looking at the output of this transmitter on a spectrum analyzer and seeing all the harmonics, it was clear that that's not the case
Ah, right. Thanks for the reply
Where did you ever get the idea that moving electrons release photons?
Finally, someone else mentions this...👍
Modern physics.
accelerated electrons release energy so yes they release photons
what is the purpose of ground plane ?
The emf is free. I'll not be paying some g-man.
3:55 oh look like you wrong there. PNP E not connect ground like NPN because Ice=minus
Isnt anything under 100mw ok?
Oh dear. It could have been so much better. (It could have been an actual AM transmitter).Why create a square wave? That will simply waste power and cause a lot of interference. You've got a sine wave, why not use it? That's what the transmitted signal should be anyway. The modulation method might work, but will need alteration to actually allow linear operation with audio. Better to use series modulation of some sort.
It's a nice start for experiemntation, but will need some changes if you want to actually use it as, for example, a pantry transmitter or even a broadcast set.
Can you please make a FM Transmitter
Cool!
hi iam very curious, can it produces magnetorestrictive effect if ferrite core+permanent magnet was present in coil arrangement?
if you read about ultrasound generator there are 2 type : piezo(ceramic) n magnetorestrictive(coil) based, both of them commonly work around 30 - 40 khz ranges, yours was 1000 khz!
Could you give a link to the site you found that antenna capacitance calculator ? I can't find it and I want to be able to make a good impedance match to get the most out of this circuit.
Oh nvm I saw the link in the bottom-right corner at 08:03
Very good video , but you’re microphone makes hashing noise..
how did you measure power?
Now how do you transmit information without waves, from proton to proton?
probably why the range is so bad is because the only transmitter schematics you can get is for low power transmitters in the micro watt range.
the fcc and arrl very carefully guards the schematics for transmitters for anything higher than a small fraction of a watt so if you want even to make 5 watt transmitter you need an fcc license and be a radio engineer.
@HyperspacePirate >>> Great video.
HSP - I have a Question - and I Know you have the ability to answer. I've Subscribed to help your efforts and here's my question and I'm asking for your time yes that's what I'm doing
What would happen if I built a '2 x tower Tesla Coil' - only it has 110 pancake coils making up both towers so that's 2 towers with 110 pancake coils as opposed to a single wire aircoil these have 220 Pancake Air Coils all in 2 stacks - you got that so far?
Now I'm going to be weird and supply all 220 pancake aircoils with 3 different wire supplies and have all 660 wiring circuits all connected to a Really Big Transformer and balance it all off with some capacitors. The Pancake air Coil circuits are going to be 110v at 50 cycles.
Absolutely Not Wired like a Tesla Coil but apart from what is said that's what I want.
Now I'm going to hit those towers with a very powerful 8 Hertz and hold my 8 Herts for over 4 hours.
A. What's going to happen to the 220 pancake coils and structures holding them?
B. What's going to happen to the transformer and all the capacitors?
C. In your own words please describe the environment.
Why add all the amplifying components if the maximum current draw from the antenna is only a few tens of milliamps? Yea sure you impedance matched it but the Q factor of that is so low that your not gonna be pulling hardly anything from your source. You could probably get away with attaching your antenna directly to the output of your colpitts.
Im willing to bet you had FCC vehicles going around your general area for a day or two after this experiment, trying to find that source of interference.
HF is like a dark art to me. I don't understand it and it makes a lot of weird noises.
sounds like me when i wake up
Electrons do not release photons when traveling up and down a conductor.
you are also mixing current and power, geez...
why didn't you use another 555 to make the 1MHz ?
Is this legal as long as it transmits a few feet?
No it’s against the law !
Is it possible to create an am transmitter without the use of a power supply?
? You mean without a bench power supply?
i mean if there’s a way to transmit radio signals much like how a spark gap transmitter works but without the use of a power source or batteries. I’m no expert on this field, but apparently such a device is possible.
If you see repeating comments it’s because they weren’t going through for me
@@joemawmaw8609
Only example of that I'm aware of is a steam turbine with a generator used to generate AC at the transmitting frequency
en.wikipedia.org/wiki/Grimeton_Radio_Station
@@HyperspacePirate I sent you a link to schematics for such a device that may exist here but TH-cam kept removing my comment for seemingly no reason. I sent you an email with the link if you’re interested, would love to know what you think
YOUR EXPLANATION of an AM CARRIER is COMPLETELY INCORRECT. Go do some research on single sideband, which is one sideband of AN AM SIGNAL, having removed the opposite SIDEBAND, as well as SUPRESSING THE CARRIER. There is no "envelope," and AM modulation does not affect the carrier as you claim. SIDEBANDS That is the key word
*The FCC would like to know your location*
in the C equation, what is the value of Len, Fre and Dia you used?
www.everythingrf.com/rf-calculators/whip-antenna-calculator
@@HyperspacePirate do you have any email contact where we can talk?
Error at 08:39 ? If P=10^-10 Watts, then Log10(P)=-10, and that x10= -9 dBm ? Or am I missing something?
Cause dBm is referenced to milliwatts, so 10^-10 W = 10^-7 mW = -70 dBm
Ah, so that’s what the “m” stands for! Looked it up (just now) at en.m.wikipedia.org/wiki/DBm
@@DavidEsp1 Yeah it can be confusing between dB / dBw / dBm. To add to the confusion, in audio, dB are usually 20*log10(X) instead of radio where its 10*log10(X)
@@HyperspacePirate Yes that one already gotcha-d me. They’re not really different in meaning, both are power, it’s just that in audio-land it’s amplitude (traditionally voltage, now digital) that gets measured and displayed as waveforms (in DAWs and NLEs). So since power is voltage squared (and in log-world squaring becomes doubling)...
@@HyperspacePirate Just don’t get me started on dB differences for mono and stereo ! Loudness levels for mono generally need to be halved (-3 dB) as compared to those for stereo. Based not on simple maths but a messy compromise - in objective reality depends mainly on how identical the sounds on each channel are.
I (and a pro I sought advice from) were “gotcha’d” (in my case badly) by that one (I guess no mono final mixes loudnesses recently experienced in that pro‘s broadcast world).
1. Put a Vacuum sphere on the top load. Better Signal
2. Just use a pwm to pulse the 1mF coil at 9ms better signal and POWER
3. Most importantly, the ground rod needs to be In between the Inductor and capacitor. All together better Geometry Less parts and materials.
Me gustó mucho, tendrás un diagrama de 50wats
What software do you use to design your circuits?
KiCAD
@@HyperspacePirate thank you :)
I notice a lot of noise in your audio recordings. Great content otherwise :)
Привет друзья ищу команду энтузиастов которую тоже хотят полететь в космос и построить ракету для начала если есть желающие и отважные люди пишите мне обсудим этот момент
@Edward Wilson @moojvyin
This once again reminds me that I'm actually stupid