Geiger Counter Case for GK-mini V2.x

This is a compact case designed for GK-mini geiger counter kit, version 2.x.


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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 version 1.5 of the kit. I have not tested this enclosure with the current version, but I expect it should work. This new case is based on my 1.5 version, and with input from the kit's designer. (The photo shows the older kit in the new case, which is why there are only three display screws.) If you have the earlier version with three standoffs, you should check out my other design here:

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
•Jacks for power, serial data, and audio allow for both tethered and standalone use

Materials and methods

Print with supports, solid infill, 0.15 mm layer height. A threshhod of 85 degrees will provide optimal supports in Cura since there is only one overhang that needs them. For material, I used eSun PLA+. You will need to run an M3 tap though the screw holes. Alternatively, you could probably drill them out and use threaded inserts. 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 socket, 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 socket

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.

4x 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 50-00082 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)



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Mini apophysis 040822 23nabell published this design ago