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--- building instructions ---

Two things to watch out for: the LCD contrast is adjustable via the trim-pot, and will probably need adjusting to see anything when power is first applied. Also, make sure to run the PS2 extension wire through the case BEFORE soldering...

• IC1: PIC18f4550
• 40 pin DIP socket
• IC2: 5V regulator 7805cv
• IC4: 3.3V regulator LD33V
• Capacitors:
  • C1: 100uF
  • C2, C3: 22pF (ceramic)
  • C4: .1uF (ceramic)
  • C5: 10uF
  • C6: .1uF
• Resistors:
  • R1: 10k (MCLR pull-up resistor for PIC)
  • R2, R3, R4: 390 (led current limiting resistors)
  • R6: 200 (for the midi line)
  • R7: 10k trim pot
  • R8: 200 (for the midi line)
  • R9: 1k
• J1: barrel connector
• J2: Female MIDI connector
• PICKIT2 Connector: 6 header pins
• Q1: 8MHz crystal
• LEDS: one red (LED1) (main power), one green (LED2), one yellow (LED3)
• (3) LED holders
• (1) Custom PCB
• LCD Panel
• Custom pre-cut / drilled enclosure
• (2) 4-40 nuts
• (2) 4-40 lock washers
• (6) 4-40 screws (4) 1/4", (2) 3/8"
• (1) PS2 Extension cable
• A few inches of ribbon cable.

• Soldering Iron and Solder: A 15 Watt iron will may get the job done, but it'll be easier with a 25 or 35 Watt iron. Don't lose sleep purchasing your first iron; any cheap RadioShack one will do. We like small chisel or screw driver shaped tips (say 1/16th of an inch wide), but personal preference plays a big role. The goal is to use a tip that's about the same size as the pad you're soldering. This way you get you get as much surface area contact as possible (better for heat transfer) but are still small enough to avoid touching neighboring pads.

  For solder, we recommend .02 or .031" diameter, rosin cored flux, tin-lead solder, either 63/37 or 60/40, whatever's cheaper. See our soldering guide for explanations. Lead-free solder is a little bit harder to use since it "wets" metal somewhat slower and has a slighty higher melting point. If your kit has sat on the shelf for a while (a year), some steel wool or a pink eraser is useful to remove oxidation from the components and board before starting.

• Needle Nose Pliers: Used to clinch or bend component leads.
• Helping Hands: Two aligator clips on a heavy base that are useful for holding wires while you solder them.
• Flush Cutters: Used to trim leads close ("flush") to the board.
• Solder Sucker or Solder Wick: Used to remove solder.
• Clamp: A table top will be fine for most of the job, but a clamp can be handy, especially when removing components.
• Multimeter: To check your work.
• Wire Strippers:
• Screwdriver: Either phillips or regular will do for putting together the case.

• C2, C3: 22pF (ceramic)
• C4, C6: .1uF (ceramic)
• R1: 10k (MCLR pull-up resistor for PIC)
• R2, R3, R4: 380 (led current limiting resistors)
• R6: 200 (for the midi line)
• R7: 10k trim pot
• R8: 200 (for the midi line)
• R9: 1k
• Q1: 8MHz crystal

Adding shorter components first lets you rest the board upside-down on a table without the parts falling out because taller parts leave a gap.

To keep components in place while soldering, clinch (bend / splay) the leads outwards. On ICs (like 16 pin DIPs--none on this board), do this for two opposite corners. This is actually what automated machines do to keep chips in place while the boards are run over fountains of liquid solder (wave soldering). Some people don't clinch leads because it makes removal harder.

Pre-bend the resistor leads before inserting to keep from damaging the board and resistor (not doing this isn't the end of the world). First hold the resistor above it's position, then hold the lead with pliers next to where the bend should go and then fold over the lead. You can also wing it with fingers. Another benefit of using pliers is that you prevent the joint between the resistor body and lead from being stressed. Resistors and most other components should be inserted as far as possible; this means lying flat for resisitor. It's convention to install resistors so their code can be read left to right in the same direction as the silk screen (tolerance band on the right).

See our soldering guide for up-close, slow motion video of good and bad soldering technique.

Use flush cutters after soldering to trim the leads.

Now add the rest of the components to the PCB, including the:

• MIDI Connector - give the solder enough time under heat to travel up through the holes to give the connector extra support.
• Barrel Power Connector - solder one pin first and check the part's alignment. It's easy to re-align by re-melting one pin, but very hard after two or more pins have already been soldered.
• 6 pin header for re-programming through the PIC-KIT or ICD2
• IC4: 5V regulator
• IC2: 3.3V regulator
• C1: 100uF capacitor (longer lead goes in positive side).
• C5: 10uF capacitor (longer lead goes in positive side).

First cut off a few inches of the male-end of the PS2 extension cable, and then string the end attached to the female side through the case as shown. Now strip off about 2 inches of the black insulation and string 2 ferrite beads on the blue line (clock), and 1 on the black line (ground). These help to limit noise that can cause the MIDIATOR to not work on some controllers. They're basically like small inductors that add impedance at high frequencies (>1MHz). Add some electrical tape around the beads to keep them from conducting electricity if they touch other components. Note: some kits ship with longer beads, this is OK. Solder in the PS2 wires from the top as shown.

• Pin 1: N/C (not connected)
• Pin 2: N/C (not connected)
• Pin 3: Yellow (attention)
• Pin 4: Blue (clock)
• Pin 5: Brown (data: Controller -> MIDIATOR)
• Pin 6: Red (power, 3.3V)
• Pin 7: Black (ground)
• Pin 8: Orange (command: MIDIATOR -> Controller)

Some clamps can be helpful to free your hands to hold the iron and solder.

LED1 on the PCB is the main power LED, LED2 is the sign-of-life LED. Feel free to use whichever colors you'd like for each function.

Use about 2-3 inches of wire to span the gap between the pcb and the front face of the case. First trim down the lead a little bit, then add some heat-shrink tubing if you have it, and then wrap the wire around the LED lead. This can be a little tricky, but some helping hands help out a lot. Also, pre-tining the wires is very helpful. Do this by holding a tinned-iron on one side of the wire, and then melting solder on the other side. Use electrical tape if you don't have heat-shrink tubing to insulate the joints.

Use a couple inches of the ribbon cable to attach the LCD. Be sure to have the wires coming out of the back of the LCD so it can fit flush against the inside of the front face of the case. Also, note the pin numbering is a little strange on the LCD panel; pins 15 and 16 are on the right of the picture, and 1-14 count backwards from the left edge.

The connections are as follows:

• LCD Pin 14 --> LCD2.1 (on pcb)
• LCD Pin 13 --> LCD2.2 (on pcb)
• LCD Pin 12 --> LCD2.3 (on pcb)
• LCD Pin 11 --> LCD2.4 (on pcb)
• LCD Pin 6 --> LCD1.1 (on pcb)
• LCD Pin 5 --> LCD1.2 (on pcb)
• LCD Pin 4 --> LCD1.3 (on pcb)
• LCD Pin 3 --> LCD1.4 (on pcb)
• LCD Pin 2 --> LCD1.5 (on pcb)
• LCD Pin 1 --> LCD1.6 (on pcb)
• other LCD pins are N/C.

If the PIC's pins don't line up to the socket, you may have to bend them inwards slightly by pressing a row against a table top.

Use the smaller 4-40 screws to secure the PCB inside the case. Screw everything down completely... this will take a bit of force since the screws will be cutting threads into the plastic..

First put the LED holders in the case and then insert the LEDS into the holders. This can require a little expanding of the LED holders to get the LEDs to snap in place.

The LCD may take some fidgeting to get inside its hole. Try sticking one of the shorter edges in first. Secure in place with the 3/8" 4-40 screws with the serrated lock washers.

When power is first applied, one of the LEDs should be blinking and the screen should be blank. Adjust the LCD's trim-pot so that the LCD actually displays some text. If no lights are blinking, it's time to recheck some connections, or email us for help trouble shooting the circuit.

Finally, close the case and secure with the four black screws.

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