Raspberry Pi Stack Exchange
Raspberry Pi Stack Exchange

Questions tagged [pifm]

a software used to turn the Raspberry Pi into an FM transmitter.

Note that unauthorized wireless tranmissions might be prohibited by state or federal law or respective regulations.

27 questions
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3 answers

PiFm dBµV/m without an antenna

I have been wanting to tinker with the Raspberry PI to learn more about electromagnetic frequencies; however, before initiating anything, I read the legal debates regarding PiFm. It appears that both Industry Canada and FCC's regulations regarding…
Ethan
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3 answers

Problems with Pifm legality

There is a lot of discussion online about whether using Pifm is okay because it is low powered, or whether it is very bad because the square waves cause a lot of interference outside the FM band. With something along the lines of a 30cm antenna, is…
andrewmh20
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1 answer

GPIO affected by audio playback

I recently found the PiFm project which sends a FM signal through a GPIO pin to effectively create a FM transmitter out of the Pi. A problem arises when you do a normal playback of a .wav audio file with mplayer or aplay. After you did this the…
WalyKu
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PiFM on another GPIO

I want to make my own Pi Radio using PiFM on my Raspberry Pi 2, but i have a display already mounted on pin 4. Can i use some other GPIO pin for mounting antenna ? And if i can, which is the best GPIO for broadcasting ? Thank you for all of your…
Joe Dimaggio
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3 answers

PiFM not transmitting on some frequencies

I was playing with the PiFm on my Pi and successfully transmitted the sound.wav on a specific frequency. That is 94.5 . But when I am trying to do the same on 89.7 , it does nothing. I changed absolutely nothing but the frequency. What would be the…
Kostas Demiris
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1 answer

Node.JS, PiFm and SetTimeout()

I'm working on an audio installation involving PiFM (https://github.com/oatmeal3000/pi2fm) that I want to play random audio files from a large selection of .wavs. My plan is to randomly select an audio file from this selection and then pass it to a…
heroZero
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Communication system using PiFmRds between two pis

I would like to use PiFmRds as a communication method between two of my Pis. I would like to be able to encode text or other data into the RDS RT (64 chars) and then decode it once received. Or even generate some sort of sound (e.g different pitches…
cobra12
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PiFm on raspi-zero

I'm having some issues with PiFm on the raspberry pi zero - I found this thread but nothing to alleviate my problem. PiFM not working for me I installed PiFm on a raspi-zero and it seems to be nearly working. I can get only a single tone (or…
bk79
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1 answer

Ffmpeg Piping output to pifm

I am trying to convert mp3 audio files on the fly with ffmpeg since pifm(a program to transmit over the FM band) only takes a specific file. I was told I could use: ffmpeg -i input.mp3 -f s16le -ar 22.05k -ac 1 - | sudo ./pifm - But ffmpeg returns…
NULL
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Pi as HF ham band transmitter and FM repeater

If the pi is able to transmit fm signals from 1 to 250mhz wiht pifm and it has been used as an HF qrp transmitter why hasnt it been further developed as an HF transmitter with a small cheap amplifier? Also if it does transmit in the 2meter ham band…
Learner
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Raspberry Pi / Low-power FM transmitter?

I recently got a Raspberry Pi 400 and I tried this https://github.com/markondej/fm_transmitter without an antenna. The range was approximately of about 5 feet, from what I could notice. Now I've heard a lot about square wave harmonics and Raspberry…
Nicolas Mailloux
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What's the maximum rf fm signal that i can generate using raspberry pi?

I am planning to create a raspberry pi based monitoring system where my raspberry pi acts as a transmitter. I learned that we can use pi to generate FM signals from RPiTX project. I am planning to generate a BPSK modulated signal using my pi and…
Madhevan Ramalingam
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1 answer

Arecord: "main:828: device or resource busy" when run via systemd service, but works fine from CLI

I have a python script which, when a GPIO button is pressed, launches an arecord process. This records audio from a USB microphone (plughw:CARD=GS3,DEV=0) and pipes it to another program for modulation and eventually transmission via rpitx. I spent…
Micah Vertal
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I think my PiFM just broke my Raspberry Pi

I followed the PiFm instructions to broadcast a .wav file on 87.5 MHz. I connected my antenna to GPIO 4, but nothing happened. Then I unplugged & tried again, but got the same result. I think I may have touched more than one pin at once with the…
12buntu
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auto start using /etc/rc.local or /etc/init.d not working

-My problem: I can't get autostart to work (/etc/rc.local or /etc/init.d) /etc/rc.local screen never boots and kills the pi, which then needs to be re-flashed to work again. /etc/init.d no auto start. Pi is still alive. /etc/rc.local I can not ssh…
Duffman
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