PROJECTS: TOY MUSIC SEQUENCER
2c. Attach the terminal block connectors around the perimeter of the board
and plug the microprocessor, op-amp,
and decoder chips into the IC sockets.
Solder the 3 wires for the programming
port onto the 3.5mm audio socket. Now
solder the wires to J1 on the PCB. The
tip of the socket is soldered to the lower
pin on the PCB, and the ring (middle) of
the socket is soldered to the middle pin
on the PCB. The sleeve (inner contact)
on the socket is soldered to the top pin
on the PCB. Screw the backshell onto
the 3.5mm audio connector.
3. DRILL THE FRAME
3a. Print the lid template from makezine.
com/13/sequencer. Unscrew the lid.
Trim the template, center it on the lid
panel, and tape it in place. Then drill
¼" holes through the panel for each
of the 4 shape pegs and the 12 LEDs,
as marked on the template.
3b. Using a 7" bit, drill back up from the underside of the panel most of the way through the 12 LED
holes, leaving a thin fillet of wood. This lets the LED holders latch correctly.
3c. For the speaker, drill four ¼" holes
through the bottom of the frame on
the right-hand side. Drill another ¼"
hole in the bottom-right corner for
the on/off switch.
3d. Drill a 1" hole in the right end
piece, in line with the lid. This is where
we’ll add a screw later for securing
the lid closed.
3e. Print the template from Step 3a
again, this time on silver foil label
paper, using a laser printer. Use a
hobby knife to cut out the outline and
the holes for the 4 shape pegs and
their 4 LEDs. Peel off the sticker backing and affix the label to the panel.
130 Make: Volume 13