Instructions - MIDI-ITO
!!! PRE RELEASE DRAFT Hardware!!!
This is a
preliminary manual. It
is based on prototypes only.
Requirements of the final hardware may cause changes in the described
I will not
explain soldering. This kit is not
really difficult to solder, but I do not recommend it as a first
project. The order of the soldering is important. Some parts will hide
the solder points for other parts. If you mount the parts in the wrong
order, you will lock out yourself from finishing the module. Also
I strongly recommend to obey the mounting instructions for the sockets
and potentiometers with the help of the frontpanel.
Requirements and tools:
- a clean work bench with good illumination
- soldering iron 25W-30W; if possible a soldering station with
- tin-solder; the PCBs are lead free. Of course lead free tin
nice for the environment, but mixed lead/tin-solder is much easier to
handle, and it is still allowed to non professionals (at least in the
- electronic side cutter or microshear like the "Knipex Electronic
- midsized side cutting pliers or a very sharp knife like a cardboard cutter
Not necessary but helpful:
- a "helping hand" pcb holder
- adhesive tape ("scotch tape")
- a bending jig made from a strip board pcb:
I use a small piece of strip board pcb as bending jig. It is cut into
sections with two, three, and four holes between the parts legs.
All parts on the pcbs a designed for this standard grid.
Basically we will solder parts in the order of their heigth. As
mentioned above some parts will hide the solder points for other parts.
So keep the following order:
- First the rear side.
- resistors and diodes
- IC sockets see remarks in the detail section)
- pinhead rows
- Then the front side.
- 3,5mm sockets and DIN-sockets (see remarks in the detail section)
- display (see remarks in the detail section)
Details REAR SIDE
The resistors may come in two different physical sizes (0.3W and 0.6W).
The wattage does not matter for the functionality. It is
simply a question, which size was available while buying. I prefer the
larger 0.6W types, but sometimes only the smaller ones are available.
Diodes have to be placed in the the right orientation. There is a black
ring around the glass body. It must point in the same direction as the
black mark is on the pcb diagram. Please obey that the two diodes point
in different directions (guess, who steppd into this trap while
building the first prototype...).
Keep the orientation of the
in mind. On of the two transistors "looks" into a different direction!
I recommend to solder the center pin of the transistor first, and then
the outer pins.
The 330 picoFarad is brown and round:
The 10nF capacitor close to the 2x5 pinheader is printed on the rear side,
but it must be mounted on the front side. We will do this later.
socket and opto coupler:
- Solder the 8pin DIL socket and
place the IC on it. Obey the orientation of the IC. There is either a
dot or a notch (see marking on the pcb)
the pinheads may come as a single part of 2x11. Cut this with the sideplier in two 2x3 pieces and one 2x5 piece.
solder those on the pcb
That's it for the rear side!
Details FRONT SIDE
- The 10nF capacitor is printed on the rear side of the pcb, but must be placed on the front side:
Place the sockets on the pcb and solder only one pin of each socket
- Place the frontpanel on the pcb and fix the
sockets with their nuts.
- place the DIN sockets from the front thru the panel into their place. They must flush with the panel.
- put a strip of scotch tape over the frontpanel so the DIN sockets can't fall out
- solder the DIN sockets and the remaining pins of the 3.5mm sockets
- tighten the nuts of the 3.5mm sockets
- Place the two jumpers on the 3x2 pinheads. The normal position is the pin pair close to the DIN socket
That's it. You are done.