Hey everyone, I'm an amateur radio operator and field day http://www.arrl.org/files/file/2010%20FD%20Packet%20February%203.pdf is coming up soon. One of the things about field day that can be exhausting is constantly repeating the same phrases over and over and over again for 24 hours give or take. Commercial solutions exist to help with this by recording your voice and playing it back while "keying" the radio. The products usually give you a few buttons to record different phrases as well. Here is one of those products http://www.mfjenterprises.com/Product.php?productid=MFJ-434B. The problem I have is $200 is WAY too much for something like this, and I like to build things like everyone else here.
Where would you suggest I start researching?
What my project needs to do is pretty much emulate the above product. It will have a mic in/out as well as some volume adjustment and multiple message record and playback buttons. Operation would go something like this...
- Flip record/play switch to record
- Hold button you which to record voice to
- Speak into mic
- Release button
- Flip record/play switch to play
- Press message button which will key the radio and play back the audio recorded in it's associated file, and when done playing, unkey the radio (keying is done by shorting a pin from the radio to gnd)
- The circuit should be transparent to the radio/mic connection, in other words, the same mic used to record audio is also used for the radio
The real part of this whole project I am having trouble understanding is how I would record audio (3-5khz, 20 seconds) for each button (separate file on sd card) and then play back a specific audio file when a button is pressed. In other words, each button is linked to a specific audio file on the sd card.
I realize that products such as the wave shield and the voice shield exist, but that's not exactly what I need (although the voice shield is close, I haven't found any schematics or code), and in the end, the actual arduino board will not be used, I will have all hardware on one board. So what IC's or other hardware should I look into to record and play back audio files? Again, this is going to be a scratch-build project, I want to stay away from already made shields because they wont help me in the end. Also, the entire project has a budget limit of $100.
Once the hardware end is figured out, I'll be back for coding help :-[. All files; board and schematic (eagle format), as well as all code, will be posted when done. Thanks all!
If I make any progress, I'll post it.