Galak Electronics VG-211 User manual

Galak Electronics
Electronic kits and components
VG-211 Singing Snowman
Thank you for your purchase of the Singing Snowman Sequencer kit. Our kits are engineered
to provide key elements for understanding electronics design and theory. In fact, we make it
our goal to produce kits that will apply important electronic principles using analog and digital
technology, and easy to find off-the-shelf components.
Our Programmable series of kits incorporate microcontroller technology due to the simplicity of
the electronics and ease of assembly. It allows for a greater range of functionality, while
maintaining a cost effective solution for some of today’s more challenging electronics needs
and requirements.
The Singing Snowman uses a simple algorithm to access selected patterns in its internal ROM
and sequences these patterns into the LEDs and speaker. Each pattern uses 8 bytes for each
step of the unique pattern. If you are interested in learning more about the program feel free to
email us at the address listed below.
Before getting starting, make sure that your item is undamaged from the shipping process. If
you notice any damaged or missing components, please contact us immediately at (302) 832-
1978 or online at [email protected].
We appreciate your business, so feel free to provide us with any suggestions or comments you
may have regarding this kit or any other Galak Electronics kit.
Website: GalakElectronics.com
Email: [email protected]
Phone: [phone]

Kit Contents
PART DESIGNATOR DESCRIPTION QUANTITY
R2 R3 R4 R5 R6 R7 Resistor, 220Ω1/4 Watt 5% (red red brown gold) 6
R8 Resistor, 1KΩ1/4 Watt 5% (brown black red gold) 1
R9 Resistor, 330Ω1/4 Watt 5% (orange orange brown gold) 1
C1 Capacitor, 22uF 16V Aluminum Electrolytic (black) 1
C2 Capacitor, 1.0uF 50V Monolithic Ceramic (105 blue) 1
C3 Capacitor, 0.1uF 50V Monolithic Ceramic (104 yellow) 1
LED1 LED2 LED, water clear t 1 ¾ (5mm) 20° viewing angle 2
LED3-LED18 LED, water clear t 1 (3mm) 20° viewing angle 16
Q1 Transistor, NPN MPSA14G Darlington 30V 500mA 1
IC1 IC, LP2950 5V Voltage Regulator 100mA (TO-92) 1
IC2 IC, Attiny84A 2K Microcontroller (preprogrammed) 1
PB1 Switch Pushbutton, Momentary Normally Open 1
SPK1 Speaker, 16ΩMini-Tone Transducer 1
BAT1 Battery Holder for (2) CR2032 Button Cells 1
PCB1 PCB, Double-sided 3.5" x 2.0” (8.8 cm x 5.0 cm) 1
INSTR1 Instructions, Singing Snowman kit 1
PC Board Top and Bottom artwork

Creating a Music Generator
The key to creating music through a microcontroller is to generate the appropriate frequency
based on an equal-tempered music scale (A4 = 440 Hz). The following chart illustrates the
frequencies generate to create all the notes you hear in your Singing Snowman.
Note Frequency Period Note Frequency Period
C5 523.25 Hz 1911 µS C6 1046.50 Hz 956 µS
C#5 554.37 Hz 1804 µS C#6 1108.73 Hz 902 µS
D5 587.33 Hz 1703 µS D6 1174.66 Hz 851 µS
D#5 622.25 Hz 1607 µS D#6 1244.51 Hz 804 µS
E5 659.25 Hz 1517 µS E6 1318.51 Hz 758 µS
F5 698.46 Hz 1432 µS F6 1396.91 Hz 716 µS
F#5 739.99 Hz 1351 µS F#6 1479.98 Hz 676 µS
G5 783.99 Hz 1276 µS G6 1567.98 Hz 638 µS
Ab5 830.61 Hz 1204 µS Ab6 1661.22 Hz 602 µS
A5 880.00 Hz 1136 µS A6 1760.00 Hz 568 µS
Bb5 932.33 Hz 1073 µS Bb6 1864.66 Hz 536 µS
B5 987.77 Hz 1012 µS B6 1975.53 Hz 506 µS
The actual tone is generated by using the period of the selected note and dividing it by two to
determine the “on” and “off” time of each waveform. The microcontroller reads the note value
and length (stored as 16th through whole notes) and transfers these values to a subroutine that
calculates the duration of the note as the total number of waveform cycles. (Note: the duration
of a whole note is approximately one second).
For example, if the note is a half note of D5 then the following calculation is made:
Period = 1703 µS ÷ 2 →852; Length = half note = 8 x 36 →288
Thus, to create a half note of D5 the microcontroller will pulse the output high for 852 µS and
then set it low for the same duration. This will generate a square wave with a frequency of
about 587 Hz. To maintain a consistent length regardless of frequency, the microcontroller will
repeat this frequency a specific number of times based on each specific note (more for higher
notes and less for lower notes). In this case, the waveform above will be repeated 288 times to
equal a total duration of 490,464 µS. More or less the half second we want for a half note.

Singing Snowman Sequencer Schematic

Populating the PC board
Make sure to properly identify each of the
components, locating them on the layout and on the
parts list included in these instructions. Do not remove
the LEDs from their individual packets until you are
ready to mount them, as they are color-coded.
To simplify the process of populating the PCB, we
highly recommend mounting the LEDs first. The LEDs
are not labeled on the board, so follow the pattern to
the right. With the exception of LED1 and LED2 all the
LEDs are oriented with the cathode to the right,
meaning the shorter lead on each LED goes to the
right.
LED1 and LED2 are used create the arms. The shorter
leads go toward the top of the board. The rest of the
LEDs can be mounted however you like, but we
recommend using the pattern to the left for the best
results.
Once you have
all of the LEDs
soldered and
trimmed, flip the
board over and start populating the board with the
lower profile components. In this case, they will be the
resistors R2-R9. Next, mount C2 and C3.
Now, mount the socket for IC2, orienting the arc to
align with the arc on the silkscreen. Now, you can
mount PB1 and C1. Note the orientation for C1. The
positive lead is the longer lead and should match up
with the “+” on the PC board.
Finally, mount SPK1 and battery holder BAT1 again
noting the orientation of each device. SPK1 is marked
on the bottom with a “+” symbol.
You are now ready to insert IC2 into the socket. Use
caution when handling the IC, as it is static sensitive.
Orient IC2 such that the arc on the IC aligns with the arc
on the socket and carefully press the IC into place. Do
not force it as you can bend the pins. If necessary, bend
the leads inward by holding the IC at each end and
gently pressing the pins against a flat surface.

Powering up the Singing Snowman
Now that you have completed the assembly of your Singing Snowman Sequencer, you are
ready to power it up. Insert two (2) CR2032 batteries with the “+” side up, sliding the first battery
under the clip. The second battery will require pulling the clip up slightly and will snap firmly into
place. Your Singing Snowman should start up immediately. The entire duration off the music and
LED show should last about two and a half minutes. Once the entire cycle is complete, your unit
will go into a power down mode, consuming just 80 µA of power (Please note: We advise
removing the batteries for long periods of inactivity).
To start the cycle again, press the button. The first pattern in the sequence will flash all the
LEDs simultaneously while playing Jingle Bells. When the song finishes, the LEDs will start the
first sequence, sweeping the LEDs from top to bottom. Next the LEDs will light in a random
pattern. The last sequence will light the LEDs in a pendulum type motion. These three patterns
will repeat 9 times for an overall duration of about 2 minutes.
If you don’t get any response from your Singing Snowman after applying power, check your
connections. If you still don’t get any response please contact Galak industries for further
troubleshooting hints. In the event that the problem can’t be resolved, we will be happy to repair
your unit free of charge. You just pay the shipping costs.
SPECIFICATIONS:
Supply Voltage 6VDC @ 15mA
Standby Current Approximately 80µA (battery life approximately 3 months)
Sequential Pattern Downward sweeping, random and pendulum motion
Pattern Select Single pushbutton to power up sequence
Board Dimensions 2.0" x 3.5" (5.0mm x 6.6 cm) approximate
Board Material 0.062" (1.6 mm) FR-4, with white solder mask and top/bottom
layer silk screen
Finished Weight 0.9 ounces (24 grams)
Good luck and enjoy you new Singing Snowman. We appreciate your business.
Galak Electronics
Electronic kits and components
Email: [email protected]
Phone: [phone]