Heltec T114 slim case

The enclosure is designed for maximum convenience when carried in a pocket. Its dimensions are 80 (or 100) × 55.5 × 14 mm.
You can connect the buzzer directly GPIO 1.12 -> micro switch -> (+ piezo buzzer -) -> GND, but the sound will be quiet. I recommend connecting the buzzer using a transistor 2n3904 (as shown in the diagram). GPIO 1.12 is pin 44 in Meshtastic.

To assemble the device, you will need the following components:
* Heltec T114;
* standard compact antenna;
* a lithium battery up to 10 × 40 × 40 (or 60) mm;
* 0905 piezo buzzer;
* SS12D00G3 or G4 micro switch (to disable the piezo buzzer);
* 2n3904 transistor;
* resistor 1 kOm 0.25w;
* some wires and a bit of patience.