[whyitell]

This was a really fun project, thanks for this. I am sure I will be able to find some 'fun' uses for this 🎉

---

Actually I need help with the converting thing, I cant get it right. Whenever I change the sample rate it sounds way to slow.

[whyitell]

it should be sampled at 16 bit mono wav format. sampled at 22050 Hz

it's really important you sample it at 22050 a lower sample rate give much faster (higher pitch) audio a higher sample rate a heavier deeper audio

i'm using format factory here are a few screenshots:
Spoiler (Click to View)

i'm using dutch software so... but i hope this helps i also added this to the main tutorial ^-^

format favtory cna be downloaded at
http://format-factory.en.softonic.com/

step1:
open Format factory
http://prntscr.com/20kw1x


step2:
http://prntscr.com/20kwhe


step3:
http://prntscr.com/20kx0w


step4:
http://prntscr.com/20ky9x


Step5:
http://prntscr.com/20kzfm


step6:
upload the converted file to your raspberry pi

EDIT 29/10/2013 21:25 GMT +1

Also added mic support ^^ to the tutorial now you can transmit real time voice over the HF VHF band

I had it like that, exactly the same setting but it had loads of static. It worked perfectly with sound.wav but not with any of my drum and bass.

[whyitell]

just send a pm to you i would love to help you further with this problem =)

i really hope i can help you solving this do you have the same problem with other mp3's?
Spoiler (Click to View)i shall try to keep this project/tutorial up to date with new finds

I tryed with 3 different songs and all of them were extremley stacticly, so I sent you all of them.

[whyitell]

don't expect hi quality you're sending through a wire and using a credit card size computer ^^
i replied you're pm and send you the audio files i really hoped it helped

If only there was a way of playing files without all the converting fuss, I was looking at this but I dont really understand it.
Spoiler (Click to View)
I use the transmitter with the vlc media player, which allows me to transmit almost anything (internet radio stream, mic, music from my NAS-Drive).

How i did it:
You need:
-VLC Media player ("sudo apt-get install vlc")
-PiFM (http://www.icrobotics.co.uk/wiki/index.p...ransmitter)
Make a FIFO-File:
CODE: SELECT ALL

mkfifo /tmp/radio

Open two terminals
Terminal 1:
CODE: SELECT ALL

vlc YOUR_FILE_STREAM_OR_DEVICE_HERE vlc://quit --intf=dummy --no-sout -smem-time-sync --sout='#transcode{acodec=s16l,ab=32,samplerate=44100,channels=1}:std{access=file,mux=dummy,dst=-}' > /tmp/radio

Terminal 2 (cd into the PiFM dir):
CODE: SELECT ALL

sudo ./pifm /tmp/radio YOUR_FREQ 44100

--
Possible Uses:
-wireless Speaker system (as almost all FM Devices have no sound delay)
-local radio station for your neighborhood (legal issues)
-Broadcast current readings from sensors (In conjunction with espeak)
-Probably more...

[whyitell]

Did you manage to get it working, and if you use that way do you not have to convert it?

[z30n1c]

How do you send to a range for example 106.1 - 106.5? Great tut thanks

[ฬєรlєч]

Just ordered my Raspberry PI the B 512MB version, gonna try this as soon as i get it :)

[RuffledUp]

Seeing as the pi is creating square waves then broadcasting that directly without any filter present on the transmitter, won't this cause harmonic interference across other frequencies in the sidebands? Which would be a bad thing. :D

[RuffledUp]

Still, without a filter even if you were broadcasting on say 100Mhz because of the square wave and harmonic resonance you could possibly be broadcasting on say 50Mhz and 150Mhz or something like that. In reality you would probably find a signal anywhere across the frequency range.