# Small PCB Design

_General · started by gdane on Sat, Jul 18, 2026 10:31 PM_

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## Original post

**gdane** · Sat, Jul 18, 2026 10:31 PM

Anybody in the community have experience with PCB design and sourcing fabrication?

I've run into an issue with RAK boards that limits the ability to utilize flash/fram storage modules (like the RAK15001) when a LoRa radio module (like the RAK13300 or RAK13302) is present, and extended storage is an absolute necessity for microReticulum transport nodes to support more than only a handful of other nodes. The way that RAK designed their base boards only allows for a single SPI device connected to a sensor or IO slot to be addressed. Since both the radio and the storage module need to utilize the SPI bus, only one or the other can be used.

What is needed to solve this problem is a custom RAK sensor module that routes the SPI CS pin of the flash chip to an alternate GPIO on the MCU so that it does not conflict with the LoRa radio (or any other SPI) module. RAK provides instructions and example projects for custom sensor modules, but this admittedly is pretty far outside my wheelhouse, as is figuring out how to get something like this fabricated.

Any help here would be greatly appreciated.

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