Actually the PI3 RPITX uses a *square wave* HF output signal that is also frequency modulated. The square wave output means that it emits very many harmonic frequencies of the (modulated) signal. Its *unavoidable* therefore that you are transmitting on military and avionics frequencies, which is illegal everywhere and in some places can get you arrested! Therefore the rapsberry PI foundation decided to remove the electronics used for RPITX (and its older predecessor PIFM) from later PI's, like the RPI4. That is why this does NOT work on a PI4!
@@paddyomalley7913 They also won't have the hardware necessary for PIFM, as they use cheap Chinese SoC's instead of the Broadcom SoC the RPF uses for their products. These products don't have real compatibility with PI's their SoC's were simply made for cheap tablets, so they were designed to run Android, not a full Linux they also don't have as much support as real PI's.
Just wondering if there is an easy way to set up rpitx and an I2S microphone to stream audio in real-time. It sounds like a fun and useful build considering a Raspberry Pi Zero costs only 5 dollars.
@@TechMindsOfficial Thank you so much for your help. I see how SOX can turn I2S into audio but I don't know if there is an option to pass audio into RpiTX.
i wonder if RPITX can send text messages at the ISM band. I have seen in the video how to transmits audio FM plus station info; but I am interested in sending digital data I means something like packet radion! are you aware if there is a similar software that can decodes text? you are doing a great service many thx again
I tried listening in on transmissions in my area and I found one or two digitally encoded ones but I can't for the hell of me figure out how to decode them. I'm a complete noob when it comes to that stuff tho :(
It could be DMR or some other kind of digital transmission. Try using DSD Plus for decoding those transmissions. Look at some of my other videos for more information on digital decoding :)
Well, it’s kinda endless really. With the appropriate TX filters you could use it to transmit what ever you like. Even pipe live Audio into it using SOX and broadcast around your home for example. I think the point here is that these guys have made the Pi do something it wasn’t designed for. Watch out for my next video which will show some other cool real life usage.
transmit a signal that will travel great distance, even with VERY low power, you can get a signal using this software to travel thousands of kilometers and even more. I resist the urge to post amateur radio websites, I don't want to hijack the channel
I found an rf amplifier online for $10 and it could be powered from 5v. Could i connect the gpio pin to that amplifier and an antenna to get longer range? The product title says that it's a 30-4000mhz 40dB gain RF broadband amplifier module for fm hf vhf / uhf.
hey,hope you're reading this cuz i need your help,what i'm trying to do is to transmitt fm using this method in video but idk why my rpi zero w gpio4 is not working , i've tried everything but it's not working,i just wanna know is there away to change transmitter gpio to another one like gpio26 or another,cuz it seems all of my gpio pins works and only gpio4 got problems.
@@californiakayaker I'm really keen to see what young hams with coding skills could do using protocols like WSPR Etc. This is how we keep the hobby going not my oldies complaining that people aren't learning Morse! Are these old guys learning to code???
I don't know what it's output power is but on HF, I have made intercontinental contacts with power as low as 1 milliwatt using Morse-encoded on/off keyed CW decoded by ear.
@@edhare6077 That is amazing. It is estimated that you can get 100mw from a rpi. One guy was able to routinely communicate with the entire USA at a minimum with that set up using WSPR. I think that was before the typical 100W ft8 station emerged., so not sure it can still be done and where they do it ..
@@岁月封华: Here in the US, using 10 milliwatts, I have contacted 30 US states plus a handful of contacts into the Carribean and one into Europe during a phenomenal band opening. Ed, W1RFI
@@edhare6077 WOAH, no way! Man, your comment is the precise gold that got me interested and has kept me interested in this goofy but ridiculously fun field and hobby! How in the world are you able to modulate anything at that distance?! Absolutely incredible, well done, I can't wait until I've gained some additional comfort and knowledge. Take care, thanks for being one of the great comments that really gets me thinking!
When a band is open, 100 watts can pretty often achieve 20 dB over S9 at times. If we assume 6 dB per S unit, here is how it breaks down: 100 W - S9+20 dB 10 W - S9+10 dB 1 W - S9 100 mW - S7 10 mW - S6 1 mw - S4 Now, in todays work, the lower bands an easily have S4 to S6 noise at night, so 10 mW is pushing it on some bands, but on 15 meters, when the band is open, 10 milliwatts should be able to do coast-to-coast communications, albeit with weak signals. Now, all my 10 mW work was done on CW, but digital modes should be even more robust, so if yu want to try QRPP, give it a go at that power level on FT8 and see what it can do. Now, I did all my 10 mW work in the ARRL CW Sweepstakes, working 56 contacts in 34 sections in the full contest period. Naturally, if anyone else called the station, I lost, but on the "off bands" where the multiop stations were scratching for contacts, I managed the occasional QSO. My antenna was modest, too -- an 80 m dipole, fed with ladder line up 50 feet. One of these years, I may try it again but from the W1AW station, running 10 mW into their antenna array. W1AW is not quite the loudest signal on the band, compared to the big-gun contest stations, but I iwll have as much as 10 dB more antenna, so 10 mW should net me some QSOs. I will have to wait, though, until a year when no one wants to activate the station for the contest. Pre COVID, HQ often had clubs operate from W1AW, with an HQ staffer there to oversee the facility. Ed Hare, W1RFI, ARRL Lab Manager
Absolutely, you need some kind of antenna, just the GPIO pin would not really be enough. See the documentation on Github for details about which GPIO pin to use.
@@TechMindsOfficial So I tried by connecting a piece of wire approx 18 cm to GPIO 4 . But still I am not receiving any signal on my SDR. How much voltage does it needs cause my raspberry Pi 4 GPIO pin has 3.3v output
Because of the illegal nature of transmitting a FM modulated square wave, meaning it doesn't only transmit the base frequency, but also all its ODD harmonics, when the RPF discovered the PI3 could be used in this way they decided to change the hardware that made this illegal use impossible, therefore its no longer possible to use a RPI4 for this use.
@@martindejong3974 Well that's quite funny, I have a nice new rpi 4-b clone, and I'm hanging a 10cm plug wire from gpio-4, and I can transmit out 1km using the tools. Mostly just using this to test feasibility of recording & playing back fob-key door locks, and it works fine as a transmitter. Why wouldn't it work? 434mhz is no problem on these fast cpus; I'm also using a pc power supply to drive both 5v connections ( usb-c&gpio-hdr ); I haven't even yet tried to hang a proper length antenna with ground plane; This is SDR, that means the filtering is free. I think the point of this is to transmit when you only own a $5 USD rtl-sdr dongle; So using this you can tx&rx, fully programmable. Much cheaper than a hackrf
@@paddyomalley7913 All I said was that the RPF tried to make it harder to do this by changing some things around so that the default PIFM software no longer would work, but yes its possible to work around it if you are stupidly stubborn, and like the idea of going to jail. In which case you cannot blame the RPF, as they TRIED to stop you.
Hi ya, no filters at all. I’m not sure if the psu I used was cleaner than your supply. Maybe try a different power adapter to see if the signal is cleaner.
and after two months, the answer is yes. The trick is creating the data in real time, something the first pi3 can almost do. For any RF project that doesn't require exact and precise timing needs, you have a VERY low power RF transmitter with the addition of some filtering
You use an RF amplifier for that. Amplifying the audio much further will simply cause distortion, and make no difference to the transmitter range. But only try it if you have an Amateur Radio licence; transmitting without an appropriate valid license is illegal.
As long as you’re not connecting to a big outside antenna and causing disruption then I’m sure you’ll be fine to experiment. Maybe use a dummy load if you’re unsure. 👍
RPiTX mode AM soundes like they forgot the to invlude the the carrier and the gap between LSB and USB... Sounds like... not saying theay did not try to.
so how do you transmit your own voice with this program? and how do you receive as well?
Actually the PI3 RPITX uses a *square wave* HF output signal that is also frequency modulated. The square wave output means that it emits very many harmonic frequencies of the (modulated) signal. Its *unavoidable* therefore that you are transmitting on military and avionics frequencies, which is illegal everywhere and in some places can get you arrested! Therefore the rapsberry PI foundation decided to remove the electronics used for RPITX (and its older predecessor PIFM) from later PI's, like the RPI4. That is why this does NOT work on a PI4!
This is why most of us buy the $30 chinese pi 4b clones, that have no USA restrictions.
@@paddyomalley7913 They also won't have the hardware necessary for PIFM, as they use cheap Chinese SoC's instead of the Broadcom SoC the RPF uses for their products. These products don't have real compatibility with PI's their SoC's were simply made for cheap tablets, so they were designed to run Android, not a full Linux they also don't have as much support as real PI's.
The AM mode looked more like DSB suppressed carrier on the display, maybe why it sounds bad when received in AM RX mode?
Just wondering if there is an easy way to set up rpitx and an I2S microphone to stream audio in real-time. It sounds like a fun and useful build considering a Raspberry Pi Zero costs only 5 dollars.
I havnt tried it myself but I believe you can do it with SOX. Not socks what you wear on your feet but the application SOX on Linux 😝
@@TechMindsOfficial Thank you so much for your help. I see how SOX can turn I2S into audio but I don't know if there is an option to pass audio into RpiTX.
These kind of videos are very interesting. Thank you for the video!
Why my rasp crash when i press enter in menu? Just no signal on monitor, only hard reboot
Hi, what do you setup on the raspberry pi? do you solder a piece of wire or something as the antenna?
Yeh, literally just connect it to the appropriate GPIO pin.
i wonder if RPITX can send text messages at the ISM band. I have seen in the video how to transmits audio FM plus station info; but I am interested in sending digital data
I means something like packet radion!
are you aware if there is a similar software that can decodes text?
you are doing a great service
many thx again
I tried listening in on transmissions in my area and I found one or two digitally encoded ones but I can't for the hell of me figure out how to decode them. I'm a complete noob when it comes to that stuff tho :(
It could be DMR or some other kind of digital transmission. Try using DSD Plus for decoding those transmissions. Look at some of my other videos for more information on digital decoding :)
Latest version doesn’t seem to work at all with the 2019 build of stretch or buster - it will compile but it doesn’t transmit a thing.
Does this have any practical purpose? Fun demo but what can it do otherwise?
Well, it’s kinda endless really. With the appropriate TX filters you could use it to transmit what ever you like. Even pipe live Audio into it using SOX and broadcast around your home for example. I think the point here is that these guys have made the Pi do something it wasn’t designed for. Watch out for my next video which will show some other cool real life usage.
transmit a signal that will travel great distance, even with VERY low power, you can get a signal using this software to travel thousands of kilometers and even more. I resist the urge to post amateur radio websites, I don't want to hijack the channel
WSPR can use just milliwatts and travel the globe ;)
I found an rf amplifier online for $10 and it could be powered from 5v. Could i connect the gpio pin to that amplifier and an antenna to get longer range? The product title says that it's a 30-4000mhz 40dB gain RF broadband amplifier module for fm hf vhf / uhf.
Would love to have a rPi transponder for AIS.
hey,hope you're reading this cuz i need your help,what i'm trying to do is to transmitt fm using this method in video but idk why my rpi zero w gpio4 is not working , i've tried everything but it's not working,i just wanna know is there away to change transmitter gpio to another one like gpio26 or another,cuz it seems all of my gpio pins works and only gpio4 got problems.
Could this be used in a practical way like WSPR? Or is it too weak?
I know of people who did amazing things with tx rPi and Whisper.
@@californiakayaker I'm really keen to see what young hams with coding skills could do using protocols like WSPR Etc. This is how we keep the hobby going not my oldies complaining that people aren't learning Morse! Are these old guys learning to code???
I don't know what it's output power is but on HF, I have made intercontinental contacts with power as low as 1 milliwatt using Morse-encoded on/off keyed CW decoded by ear.
@@edhare6077 That is amazing. It is estimated that you can get 100mw from a rpi. One guy was able to routinely communicate with the entire USA at a minimum with that set up using WSPR. I think that was before the typical 100W ft8 station emerged., so not sure it can still be done and where they do it ..
Cheers for that mate....very interesting. What's the TX power, I'm guessing a few mW?
According to the Raspberry Pi, the 3.3-volt gpIo voltage is only a dozen milliwatts.
@@岁月封华 So 12 milliwatts
@@岁月封华: Here in the US, using 10 milliwatts, I have contacted 30 US states plus a handful of contacts into the Carribean and one into Europe during a phenomenal band opening. Ed, W1RFI
@@edhare6077 WOAH, no way! Man, your comment is the precise gold that got me interested and has kept me interested in this goofy but ridiculously fun field and hobby! How in the world are you able to modulate anything at that distance?! Absolutely incredible, well done, I can't wait until I've gained some additional comfort and knowledge. Take care, thanks for being one of the great comments that really gets me thinking!
When a band is open, 100 watts can pretty often achieve 20 dB over S9 at times. If we assume 6 dB per S unit, here is how it breaks down:
100 W - S9+20 dB
10 W - S9+10 dB
1 W - S9
100 mW - S7
10 mW - S6
1 mw - S4
Now, in todays work, the lower bands an easily have S4 to S6 noise at night, so 10 mW is pushing it on some bands, but on 15 meters, when the band is open, 10 milliwatts should be able to do coast-to-coast communications, albeit with weak signals.
Now, all my 10 mW work was done on CW, but digital modes should be even more robust, so if yu want to try QRPP, give it a go at that power level on FT8 and see what it can do.
Now, I did all my 10 mW work in the ARRL CW Sweepstakes, working 56 contacts in 34 sections in the full contest period. Naturally, if anyone else called the station, I lost, but on the "off bands" where the multiop stations were scratching for contacts, I managed the occasional QSO. My antenna was modest, too -- an 80 m dipole, fed with ladder line up 50 feet.
One of these years, I may try it again but from the W1AW station, running 10 mW into their antenna array. W1AW is not quite the loudest signal on the band, compared to the big-gun contest stations, but I iwll have as much as 10 dB more antenna, so 10 mW should net me some QSOs. I will have to wait, though, until a year when no one wants to activate the station for the contest. Pre COVID, HQ often had clubs operate from W1AW, with an HQ staffer there to oversee the facility.
Ed Hare, W1RFI, ARRL Lab Manager
Hey i tried this on my Raspberry pi 4 , but it didn't work. Do i need to attach an antenna or a piece of wire to any of the GPIO pins of the RPi ??
Absolutely, you need some kind of antenna, just the GPIO pin would not really be enough. See the documentation on Github for details about which GPIO pin to use.
@@TechMindsOfficial So I tried by connecting a piece of wire approx 18 cm to GPIO 4 . But still I am not receiving any signal on my SDR. How much voltage does it needs cause my raspberry Pi 4 GPIO pin has 3.3v output
Because of the illegal nature of transmitting a FM modulated square wave, meaning it doesn't only transmit the base frequency, but also all its ODD harmonics, when the RPF discovered the PI3 could be used in this way they decided to change the hardware that made this illegal use impossible, therefore its no longer possible to use a RPI4 for this use.
@@martindejong3974 Well that's quite funny, I have a nice new rpi 4-b clone, and I'm hanging a 10cm plug wire from gpio-4, and I can transmit out 1km using the tools. Mostly just using this to test feasibility of recording & playing back fob-key door locks, and it works fine as a transmitter. Why wouldn't it work? 434mhz is no problem on these fast cpus; I'm also using a pc power supply to drive both 5v connections ( usb-c&gpio-hdr ); I haven't even yet tried to hang a proper length antenna with ground plane; This is SDR, that means the filtering is free. I think the point of this is to transmit when you only own a $5 USD rtl-sdr dongle; So using this you can tx&rx, fully programmable. Much cheaper than a hackrf
@@paddyomalley7913 All I said was that the RPF tried to make it harder to do this by changing some things around so that the default PIFM software no longer would work, but yes its possible to work around it if you are stupidly stubborn, and like the idea of going to jail. In which case you cannot blame the RPF, as they TRIED to stop you.
Wow - your signal looks very clean; mine is really hairy - are you using some sort of filter?
Hi ya, no filters at all. I’m not sure if the psu I used was cleaner than your supply. Maybe try a different power adapter to see if the signal is cleaner.
@@TechMindsOfficial Interesting - I will! Thanks 🙂
I need a guide how to properly attach a wire to the raspberry 4 to transmit signals. Anyone able to help here?
I’ll create a video soon for this :)
@@TechMindsOfficial we are waiting!!!!!!!!!!!!
@@TechMindsOfficial Did you ever make this video? What type of wire do we need?
Is there a way to take the output of fldigi or maybe minimodem and pipe that into rpitx?
and after two months, the answer is yes. The trick is creating the data in real time, something the first pi3 can almost do. For any RF project that doesn't require exact and precise timing needs, you have a VERY low power RF transmitter with the addition of some filtering
Can one use a audio amp to extend signal transmit?
You use an RF amplifier for that. Amplifying the audio much further will simply cause distortion, and make no difference to the transmitter range. But only try it if you have an Amateur Radio licence; transmitting without an appropriate valid license is illegal.
Very interesting!
Is it possible to try all these modes out without having a licence?
As long as you’re not connecting to a big outside antenna and causing disruption then I’m sure you’ll be fine to experiment. Maybe use a dummy load if you’re unsure. 👍
Seria posible hacer un transceptor de radioaficionado juntando hackrf, raspberry, Amplificador de potencia, filtros lpf, acoplador, etc ....
How can we WSPR using this rpitx software?
There is a dedicated WSPR application for the raspberry pi, checkout my WSPR video :)
WSPR - Weak Signal Propagation Reporter - From A Pi Zero ? th-cam.com/video/8rRCK7nnJ9U/w-d-xo.html
Thank You!!
you really typed the whole url, i`m feeling so lazy
Waiting for the next video. Please
Just for... sounding like the local wiseass:
APT UPDATE
APT INSTALL xxx
Try and weep for the accumulated years wasted ^^
RPiTX mode AM soundes like they forgot the to invlude the the carrier and the gap between LSB and USB... Sounds like... not saying theay did not try to.
@@DasIllu Yes is typical double sideband