This clock announces the time using your own voice!
I put it together as a tribute to the old Popcorn service in Northern California. You could dial POPCORN from any phone, and a recording would tell you the time of day.
Originally, I wanted to use Joanne Daniels' voice (she was the voice of Popcorn), but I couldn't get enough samples of her saying all the numbers. Pat Fleet (the lady that says "A, T, and T") actually offers recordings, but you have to pay for them. So I settled on using my voice, and it's easy to substitute your own.
First, a little demo, then flip to the next page and I'll show you how to make it on a breadboard.
Q: How does it work?
Audio samples are stored on an SD card. The time is tracked with the DS1307 RTC. The microcontroller polls the RTC every second to update the display and watches the big red 'announce' button. Once you hit the button, the microcontroller plays the appropriate samples based on the current time.
Q: How do I use my voice?
You just record your voice and copy to the SD card. I'll show you how in a bit, but it's easy.
Q: Can I make it do x?
Probably. You can download the code on the next step - you can poke through it and change things fairly easily.
Q: What are the technical details?
It's a Parallax Propeller running at 80Mhz connected to a DS1307 Real-time clock and an HD44780 8x2 Character LCD (4-bit interface). The Propeller manages everything including audio playback using rayman's excellent wav playback objects. 16kHz mono or stereo wav playback is supported.
Here's a walkthrough of how it works. Note that I'm using an LCD UI module and Propeller Platform SD, but this instructable will show you how to build it with a breadboard.