Weekend Project: Arecibo Decoder with P2
Reinhard Posts: 470
edited 2023-02-25 14:11 in Propeller 2
In 1974 a message was sent to potential extraterrestrials.
The good news for aliens is: With the P2, this message is easy to decode.
An advanced alien naturally has a VGA monitor.
Unfortunately I can't attach the wav file, probably too big.
I detected the 941 Hz with the Goertzel Algo and converted it to a VGA image.
Setting the correct trigger threshold requires some patience. The rest is easy.
So if I can do it, the aliens can do it too.
For a moment, I thought you were talking about the WOW! message, LOL! Need more caffeine this morning.
Great project! Here is a link to the audio: https://en.wikipedia.org/wiki/File:The_Arecibo_Message.wav
Direct download link: https://upload.wikimedia.org/wikipedia/commons/7/71/The_Arecibo_Message.wav
I found the ogg file for download
I can decode it with the octave m-file.
It has the same sample rate as the wav - file, that I use, think this important.
It is a Dual Ton Multiple Frequency File. (DTMF) -- 941/1336 Hz
I trimmed my decoder to detect 941 Hz.
At the moment not tested with P2, but it must work also.
I forgot from where I the wav - file received.
Now I finish the small project and go to other themes.
If any is interest, here are all files.
Needed is the P2 Eval Board with AV Expander and optional a VGA monitor.
If no monitor on desk, you can use the Build_n_Run octave script, this received the data from P2 and show the result as image.