Geiger Counter Case

A compact, portable case for the GK Mini geiger counter kit


Creative Commons Attribution Share Alike

Commercial use is allowed, you must attribute the creator, you may remix this work and the remixed work should be made available under this license.

Learn more or download attribution tags



THIS IS FOR AN OLD VERSION OF THE KIT! If you have the current version (with four standoffs) check out my other design here:

This is a case for the GK-mini geiger counter kit. More info on the kit can be found by the link above. I am not the seller or designer of the kit, just a user who wanted a compact, portable enclosure. Note that I have an older version of the kit (board rev. 1.5). This case will not work with the current kit version, which has slightly taller standoffs. The design was done in Fusion360. If you want to modify it, that is probably the way to go.

Design goals/features:
•Compact, easy to assemble design
•Power switch
•Second switch for backlight control or mute
•Selector button
•Space for two parallel SBM-20 tubes (just barely!)
•Jacks for power, serial data, and audio allow for both tethered and standalone use

Materials and methods

Print with no supports, solid infill, 0.15 mm layer height. I used eSun PLA+. I tried to size the screw holes so that, in a pinch, you could just force the screws in. However, it is better if you can run an M3 tap though them first. Alternatively, you could probably drill them out and use threaded inserts. Note that you may need to bend the IR receiver on the board back in order to clear the wall. Be sure to use a bit of foam or hot glue to keep the SBM-20 from moving around.

Since space is tight, things need to go together in a certain order.
1. Install tube, switches, bottom TRRS jack, and LCD
2. Install main board, being careful to line up the header pins on the LCD with the sockets on the board
3. Install the pushbutton and upper TRRS jack

Power from the data/power jack is run through the power SPDT power switch. Thus, the power switch actually selects between the internal battery and external power, when present. The jack is wired specifically to keep the power from doing bad things to the data lines during live insertion.
T - Tx
R - Rx
S - +5V

The second 3.5 mm jack can be used for headphones. You will probably want to use some sort of inline analog volume control to save your ears.

3x M3 x 12mm flathead screws (I used black hex type because they look cool)
4x M3 x 10mm flathead screws (Phillips is nice here, because you have to remove them to change the battery)
2x Tensility 50-00041 3.5mm TRRS jack
2x E-Switch 100SP1T1B1M1QEH micro toggle switch
1x C&K 8125SHZBE pushbutton (With clicky tactile feedback!)
PL2303HX UART adapter and 3.5mm TRRS cable (ebay)



Issues are used to track todos, bugs or requests. To get started, you could create an issue.


Mini apophysis 040822 23nabell published this design ago