08 Jan

Wireless RGB Pixels – Prototype PCB (v1.2)

The prototype PCB for the wireless RGB pixel is at v1.2.

Front of v1.2 PCB pinout (top) and back of PCB showing NRF module (bottom)

This version fixes a mistake I made with the power pins (I misread the data sheet) and does away with the RC pin multiplexing simplfying and standardizing the SPI comms with the NRF24L01. This also means there is no serial debug output from the ATtiny.

Initial radio range tests with the test firmware are disappointing. Comms was spotty and random. I experimented with the various power levels and have tried removing some of the PCB material and re-orienting the NRF module at an angle to see if that made any difference but it didn’t appear to.

Cropped PCB material near NRF PCB antenna on left, NRF soldered at an angle on back of PCB on right.

Cheap amplified NRF modules from ebay actually reduced the range compared to a standard PCB antenna version.

It will be interesting to compare the non Arduino-IDE based firmware with the test code in terms of radio range and comms reliability. I will update when available.