DIY Kits - Assembling and Mounting

Time to finish your Gecho!

If you received some version of the DIY kit, there is a few things to do, before you can enjoy the music.

Soldering THT components

In the parcel you should have received three black 3.5mm Jack connectors, those are for headphones outputs and pickups input. There is also a magnetic sensor (has 3 leads, looks like a transistor), two microphones, and in case your kit is of "Adept" version, a CH340G chip wrapped in piece of polymeric foam. Don't throw it away, this foam is good to put under the board, so it spans between both mounting holes, and will be held in place by screws. Two bronze-finish self tapping screws are included.

Depending on your selected powering scheme you might also receive one or two battery holders of AA or AAA type or contacts for 18650 Li-Ion rechargeable cell and charging module, installation of which is described in detail here.

Position of THT elements you need to add, plus wiring for batteries, looks like this. The picture displays bottom side of the board but shows top side mounted components too.

Jack connectors and microphones are mounted on top side, magnetic sensor and USB driver CH340G on bottom side.

Take care when mounting microphones, as their polarity is critical. Plus and minus mark is present on the board, and plus mark is usually present on a microphone too. If not, you can rely on eccentricity of the leads and place them in a such way that they end up farther from board's edge.

Be sure that the Jack connectors are pressed against the board well so they sit on it tightly and without a gap, otherwise it won't look good.

Magnetic sensor pads are close together. Make sure to either bend their ends, so there is no chance of short circuit from the middle lead to other two lead's pads, or use some insulating material - e.g. heat shrink tubes. Also, it is good to shorten them by approximately 5mm first. When bending, make sure the direction is away from "front" side of the element (the one where the marking text is).

After soldering everything, you should get something like this. Note how thanks to shortening of the magnetic sensor's leads, it got positioned roughly in the centre of the board. It does not need to be exactly in the centre, plus minus few millimetres don't really matter. And if you forgot to shorten them, it will work fine (it's not worth reworking and risking damaging something).

The board shown here has also the MIDI extension installed, please follow this guide to learn how to add it.

Expansion Pads

Should you want to wander further within your DIY efforts, here is a quick description of solderable pads that let you use various interfaces and signals from MCU. Most of them are occupied by LEDs but those are not really in the way, apart from acting like a pull-down or pull-up resistors, so please take this into consideration. First two rows of LEDs (red and orange) are driven by active high logic, therefore wired in a common-cathode way, the rest (blue and white) are driven with active low, so wired as a common-anode.

For easy reference, colour of pads in following picture equals colour of LEDs, and the four CV pads (wired to IR distance sensors, but possible to safely override with external voltage in 0 to 3.3V range) are shown in green.

Got our box as well? Here you can get some ideas about how to put everything together.

Comments

Hi Mario,

I received the Gecko last week. Thanks.

I soldered the three jack connectors without any problem.
I have a problem with the magnetic sensor.
Is it mounted on top side ?

I see well where to mount the sensor in the three holes of the board.

Can you send a photo to illustrate the position of the sensor ?

Thank you for your help.

Gérard

Hi Gérard,

Glad to hear it arrived - and hope you like it! :)

Good idea, one picture is worth a thousand words - I've added a photo so there is no doubt about the placement and orientation.

Cheers,
Mario