By Dave Decker
In this project, we’re going to introduce you to a unique
talking voice memo alarm clock/MP3 speaker with
customizable alarm music. The device can capture a tune
from your PC or MP3 player and store it in internal,
non-volatile Flash memory for use as the alarm. In addition,
we’ve also compiled an online library of royalty-free music
clips and sound effects, and created a unique way of
downloading them directly to the clock. Either way, music
is retained indefinitely, even without power.
A very unique feature of our clock is the capability of
recording voice memos using a built-in microphone. This
feature makes it easy to leave yourself a wakeup reminder,
since recorded voice memos can also serve as the alarm.
A 10 minute snooze timer, progressive alarm volume (the
alarm gradually gets louder), and a daily alarm are included.
The 4 1/2” cube-shaped, injection-molded case
includes a translucent acrylic shade illuminated from within
by 16 high brightness LEDs. The LEDs allow the clock to
double as a nightlight and they create entertaining
synchronized lightshows when the MP3 speaker feature
is used. A four-digit auto-dimming LED display shows the
current time, indoor temperature, scrolling text, and
animations while in MP3 mode.
There’s a good selection of built-in nightlight programs
to choose from including solid, fading, and random color
patterns. Some of the nightlight programs are designed to
react to their surroundings. For example, the “clap”
nightlight turns the light on and off in response to hand
claps. There’s an on-at-dusk simulated candle flame
nightlight, a “babysitter” nightlight that plays/fades out a
lullaby when it hears a baby crying, and even a sound
soother nightlight to help you fall asleep.
40 May 2009
Press the large backlit button and the talking clock
announces the current time in a natural-sounding male
voice. There’s a recessed pocket in the front face of the
button designed for a standard 1 3/4” x 1/2” return
address label. Using an inkjet or laser printer and labels
(we recommend the white polyester type), it’s easy to
create artwork featuring any university or team logo, a
child’s name, or any other design to further personalize the
clock. The button and label are backlit by a pair of white
LEDs, making them glow softly.
On the back of the device, there’s a smaller “mode”
button and a 3. 5 mm audio input for your iPod/MP3 player
recessed into the base. The mode button is used to select
the current nightlight program and to activate the voice-prompted settings menu. The talking menu makes it easy
to set the time, the alarm, and other features.
If you prefer, the clock can be set up and managed
entirely using your web browser. It listens for sounds
generated by a special webpage and responds by setting
the time, configuring the alarm, selecting your favorite
nightlight, and even calibrating the temperature sensor. It’s
as easy as clicking your mouse, and it’s a lot of fun, too!
The clock can use either the AC adapter or a standard
9V battery for power, so it’s easy to take it anywhere. The
battery also serves as a backup for the clock in case of
power failure. There’s even an integrated smart battery
charger that maintains your (optional rechargeable) battery
in peak condition.
Theory of Operation
We’ll present the circuitry in two parts: a “core”