933 MHz radio remote with two-way comms
A miniature CR2032-powered remote — custom PCB, embedded firmware and an SLA enclosure in flame-retardant UL94-V0.
The entire product fits in the palm of your hand — actually, in half of it. The 933 MHz remote runs on a single CR2032 coin cell. Underneath sits fully custom electronics and firmware written for the target microcontroller.
The challenge
Two-way radio in a package this small piles several constraints on top of each other:
- size — compact enough to sit next to a coin cell,
- power budget — everything must live on one CR2032 for a long time,
- 933 MHz antenna — designed with the PCB layout, not glued on after,
- enclosure — mechanically tough and meeting the flame-retardancy requirement.
Electronics
The project covered the schematic and PCB layout, component selection (with sleep-mode current as the top priority) and antenna network tuning. Firmware implemented a two-way protocol with acknowledgements and error checking.
Enclosure: SLA 3D print, UL94-V0
The enclosure was printed in SLA — resin 3D printing yields clean, fine detail and a smooth outer skin. Material: UL94-V0, the flame-retardancy class required by many industrial applications. The outer label was produced externally and applied to the finished housing.
The result
A working, light, flame-retardant remote with two-way radio that fits in the palm of a hand. A good example of a project that needs the whole stack under one roof: electronics, firmware, mechanics, material selection and printing — all in one workshop.