Hikari 2.0 Kit Instructions

Hikari 2.0 Kit Instructions

Hurray on your new Hikari kit!

First, let's make sure you have everything. 

  • .Hikari PCB
  • Hikari Acrylic plates (2)
  • Foam Layer
  • Acrylic Standoffs (4)
  • 6/32 Machine Screws (4)
  • 6/32 Nuts (4)
  • 6/32 Acorn/Cap Nuts (4)
  • 4093 IC 
  • 100kB Pitch pot
  • 1k or 10kA Volume Pot
  • .1 uf capacitor
  • .22uf capacitor
  • 10uf capacitor
  • 100 ohm resistor (3 or more)
  • 470 ohm resistor
  • 10k resistor
  • photocell
  • push button
  • BD139
  • BC547
  • 9v battery clip
  • speaker
  • LED (green, blue, red, or white)

If anything is missing or visibly damaged in your kit, please let us know & we will promptly send any missing pieces or replacement.

With all that squared away, it will be particularly handy if you also have all or most of these on hand: 

  • soldering iron (definitely)
  • 60/40 rosin core solder
  • ventilation
  • small flat head screwdriver/plastic tweezers (this helps with placing the headphone jack)
  • clean workspace
  • headphones (to test the jack)
  • wire cutters (having flush trim as well as snips is helpful)
  • wire strippers (some may use teeth)
  • good music 

Let us begin.

Start with resistors. *note orientation doesn't matter here*

  • R1- 470 ohm
  • R2- 10k ohm
  • R3- 100 ohm
  • R5- 100 ohm

The extra resistor will be used later.


Now let's get those capacitors. For C1 & C2, orientation doesn't matter. For C3 make sure the negative leg is towards the inside. Also attach C3 so that it lies down flat, at an angle to leave room for the LED.

Up next is the headphone jack. This step is a little peculiar. No worries. Insert 4 pins, and nudge the pin towards the output jack into to it's hole. Before soldering make sure all 5 pins connect through the board.

Now for the transistors. BC 139 attaches as shown with the metal side facing down. BC 547 needs to be inserted as shown, and pressed in to the same height as the headphone jack. Be careful with these as they can be sensitive to ESD.

Add the 9V battery clip.

Cut the lengths of wire to about the length of the holder itself. Strip them and solder in place as shown, with the black (ground) adjacent to the button's location. You will use the cut off wire to attach the speaker if your speaker did not come with wires attached.

Add the tune potentiometer, it's the 100kB one :D it may help to press the two side legs in a little to make it easier to insert.

Add the LED. The short leg should be towards the inside of the circuit board as shown. 


Clip the excess leads of all components if you haven't done so already.

add the 4093 IC, gently bend one sides legs to make the IC slide into place. Make sure the notch matches the notch on the circuit board. Take your time soldering the pins in place, as overheating the IC can damage it. 

Next attach the button. We find it best to solder one pad first, reheat it, then insert the button - be sure that the button is completely down & in place before soldering the other 3 pads. If the button isn't perfectly flat, the faceplate will not sit properly. 

Now solder the volume pot into place, like you did the tune pot. Then add a 100 ohm resistor between the outside leg of the pot & the corner pin of the 4093 IC. The photo above is after the pot & resistor are soldered in place. 

Add the photocell. Orientation doesn't matter here, just make sure the legs make contact with the pads, they're a little smaller than other pads!


Add the speaker as shown, using the wires from the 9V battery clip. You should be out of components now! time throw on the foam faceplate. Carefully peel and place the foam sheet to match the board and pass over the speaker & battery holes.

Hot glue the speaker (yours may look different - we switched to round speakers in late 2018)

Hot glue the battery clip as shown, we normally snap the "clip" part of the 9v clip off with a pair of pliers to make inserting the battery easier when assembled.

Drive the 6/32" machine screws through the backplate throught the standoffs & into the board. The holes in the PCB are 1/8" and will be tapped/threaded by the screws you put through them. Screw the bolts in until the standoffs stop spinning freely. Don't overtighten into the foam layer or our Hikari will be shorter than ideal!

Then loosely put on the 6/32 nuts


Then add the faceplate & cap/acorn nuts. Adjust the nuts so the faceplate sits flat and rests on the top of the headphone jack.

Congratulations! You have finished building Hikari. Now take it outdoors & test it out. Test & Enjoy!

Troubleshooting if your Hikari is not making light or sound:

  • All parts are soldered cleanly & touching all the pads (this is the most common problem)
  • The battery is attached correctly
  • No components look burnt up from assembly
  • All prices where orientation matters (battery, C3, LED, BC547, BD139, 4093)
  • Often when assembling Hikari we have found the photocell proves to be tricky point. Try touching up those connections if you/re still without sound.
  • If all fails, and you can not bring your Hikari to life, contact us with pictures of your boards & what seems to be the problem & we will do everything we can to help!