Introduction: MicroGranny 2 Assembly

If you are here, you are probably about to put together your very own microGranny 2 from kit you ordered from us.

For assembling, you will need following tools:

  • Soldering iron
  • Solder
  • Screwdriver
  • Pliers
  • Wire stripper (optional)
  • Allen/Unbrako/Inbus/Hex wrench (there is one included in kit, but just in case...)

Time to complete whole assembling is ranging from 2-4 hours, depending on your experience.

If you are here to considering buying kit and you never built anything from kit nor have any experience with soldering electronics, you should probably start with some easier project (like our Trinity) or get assembled version instead.

Step 1: Kit Summary

As you can see on picture, there are lots of components that goes on board. They are carefully arranged to fit order in which you should place and solder them onto the board.

Kit is consisting mainly of two boards:

  • one smaller (highly populated with various chips)

You'll be working on both of them at same time, soldering same type of components one after another.

Step 2: Placing SD Card

Put SD card socket onto board and align it properly. Solder socket sides first. This way socket is not going to move, while you'll soldering actual connections to socket. It's bit tricky, so take your time.

NOTE: Bottom of card socket is partially made out of plastic. Although it's not made of butter and it can withstand some heat, be careful with soldering iron and try to NOT melt plastic. You may not be able to insert SD card or use socket at all, if you do.

Step 3: Diodes

Ok, here we go!

Let's start with diodes.

There are:

  • single black diode which belong on top board
  • bunch of glossy ones. One belong to top board, close to black one and rest of them are placed on bottom board.

Gently bend their legs so they fit in and put them in corresponding places. It's generally better to do this with all components with straight legs, than putting first lead in and then trying to squeeze other one in. Push them all the way to the board, until there is no gap.

NOTE: Diodes are polarized components, so it actually matters, which way you put them onto board. There are hints how to position diode at each place, so it's really easy, but it's good habit to double check it, before soldering part to board. You will save yourself a lot of time and trouble.

Step 4: Ceramic Resonator

Resonator belongs to voice board and it does not matter which way you place it onto board.

Step 5: Resistors

There are lot of resistors in kit. We tried to make it as simple as possible, and put character labels (from A to E) to mark places where most commonly used resistors are supposed to go. It's really not rocket science, just make sure you pick right resistor for right place.

  • A - 7x 1K - for LEDs
  • B - 1x 1k - for red RECord LED
  • C - 10x10K - for RGB LED
  • D - 4x 1k - for pot LED
  • E - 4x 47R - for numeric display

and rest of resistors :

  • 220R 5x
  • 100K 2x
  • 2K2 1X
  • 470K 1x
  • 1K 2x

Be careful especially about these two – 47R & 470K! These two have just one band different – gold and orange (which is tricky to distinguish in some circumstances). As general rule of thumb, use multimeter, if you are not sure.

Step 6: Chip Sockets

Interface board should have just one socket, voice board contain six.

Make sure you align them in right way – there is a little notch in each socket which should match their corresponding place on boards. No big deal.

Tip: put socket in board, bend corner leads of socket, so it will not fall out of board.

Step 7: LEDs

Now, to make microGranny really shine, you should put in place all LEDs. Keep in mind that they are polarized (like normal diodes), so make sure you are putting them on boards in correct way.

  • RGB LED (one with 4 legs) – there's just one on bottom board, there's matching hint to place it correct way. Longest lead of LED is cathode, marked as +. Also there's little flat side on LED, which should match hint on board as well.
  • 3mm LEDs – only one goes to top board, rest of them goes to bottom board. Same as before, longer lead is cathode, so it goes to the +.

Step 8: Ceramic Capacitors

5x 104 = 100nF placed on top board. Rest of capacitors are for bottom board.

1x 223 = 22nF

1x 101 = 100pF

1x 102 = 1nf

Step 9: Voltage Regulators

Top board have spots for 2 voltage regulators:

  • 7805 – bend leads of package, so it will lay flat on board (see picture).
  • 78L33 – make sure you place it in correct direction (again, there's hint on board)

Step 10: Electrolytic Capacitors

These are just bigger and polarized version of ceramics counterparts.

Hints on boards should give you enough guidance. All capacitors are 10uF:

  • 3 on voice board
  • 4 on BACK of interface board

IMPORTANT NOTE: if your kit contains all electrolytic capacitors with same tall size, you'll have to do a little adjustment on voice board before soldering. Don't push capacitors all the way through boards and leave at least 3mm of space, so you can bend them sideways little bit. Otherwise you won't be able to put interface board on top of voice board.

Step 11: Buttons

Bottom board have line of 6 big buttons on bottom and group of 6 smaller ones on left. Again, this is straight forward, buttons fits on the board only in one direction.

Step 12: Numeric Display

Put numeric display on the interface board, it's dedicated place is marked by four digital 8s directly on board. Make sure dots on display are heading down, just like on board. Leads of display are little bit longer, so they are little bit tricky to push through holes at once.

Step 13: Microphone

Microphone is polarized as well, but it's really super-easy to find which way you should align it on board - it should match hint, marked with hatching in circle.

Step 14: Pots!

Six potentiometers (or pots in short) are going to be placed at top of interface board. Their respective places are marked like on picture


Although they might look all same, but there are two kinds:

  1. Two 10K Logarithmic pots
    They are marked as "A10K" directly on pot. These two should go above numeric display, in right top corner.
  2. Four 20K Linear pots
    These are supposed to go to rest of places for pots.

Make sure that pots are touching board with all four plastic legs.If not, shafts are not going to fit through holes in housing. You can quickly fix it by pushing shaft with one finger while heating up all connections including holders.

Step 15: MIDI Jack

Add MIDI jack on bottom board. It's also straight forward, like step before, with one exception: it's supposed to go on bottom of the interface board (other side then pots are placed).

Step 16: Power Jack + Switch + Audio Jacks

Power jack goes to voice board, as well as power select switch.

Audio jacks on the other hand, goes to interface board. Like MIDI jack, it's placed at other side of interface board (actually, they are next to midi jack).

Step 17: Chain Connectors

Kit contains two bent 'XXXX Headers / Connectors XXX. These serve for connecting other Bastl instruments and composing them into chain. They should be placed on sides of bottom board.

NOTE: Keep in mind that connectors are soldered from top (from surface), which is little bit unusual. Take a look at photos.

Step 18: Headers

Both boards are connected via headers. You have to solder pins to interface board and header sockets to voice board. They are placed on outer side or both boards. After you're done, you can put both of them together.

TIP: Put header you are about to solder in holes and solder just first pin. Then you can use solder to heat up just this one pin, correct position of header while holding board with one hand and soldering iron in another. After this, you can start soldering rest of the pins starting from opposite side and don't worry about header falling out of board. This way you can solder all pins in couple of minutes like a pro!

Step 19: Last Soldering Step: 9V Power Connector

You are almost done with soldering and almost about to turn off your soldering iron!

Last piece is 9v battery power connector. On voice board, just below two electrolytic caps, are four holes (2 with soldering pads and 2 without soldering pads) with plus and minus signs in between.

Shorten wires to match about size of board. Then, use wire strippers, pliers or knife to get rid of piece of insulation of power connector wires. Now, push them through holes WITHOUT soldering pads and then through holes with soldering pads. This way, cable is secured against excessive pulling while changing battery. Clever, huh?

Step 20: Mounting the Spacers

You are finally done with soldering! If you made it so far, it takes couple of minutes to have finished microGranny 2 sitting on your table.

Among remaining parts of kit should be couple of metal components

  • 4 spacers (2 small ones and 2 tall ones)
  • 4 screws (with both inner and outer threads).
  • 2 metal pads

This step is little bit hard to describe, so you probably should really pay attention to pictures.
Use metal parts like so:

  • 2 tall spacers → interface board (on right side, where is numeric display) → 2 screws.
    Screws belong to top side, spacers goes underneath.
  • 2 screws → smaller board → metal pads → smaller spacers.

Step 21: