sudomesh / disaster-radio

A (paused) work-in-progress long-range, low-bandwidth wireless disaster recovery mesh network powered by the sun.
https://disaster.radio
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Breakout board breakout boards! #2

Closed Juul closed 6 years ago

Juul commented 7 years ago

We need a breakout board for our breakout board!

We're using the Semtech SX1276 for LoRa, but using it directly requires a bunch of support components so we're instead using a module like:

They accomplish the same thing, are similarly priced and use the same footprint but the pinouts are unfortunately different. The RFM95 is the most popular module but the DORJI is a bit cheaper.

These modules have no antenna connector so we need to break them out further. Breaking out the antenna pins to an antenna connector requires impedance matching. Here's a really nice talk on doing impedance matching the easy way.

@nanomonkey is working on a breakout board that will include:

We will order a bunch of them from Seeed Fusion as soon as the design is ready.

Juul commented 7 years ago

Here's a KiCAD project with an RFM95(W) breakout. It's not exactly what we need (only two-layer, no impedance matching, wrong antenna connector), but we can copy the PCB footprint from this project.

Juul commented 7 years ago

Fitz and nanomonkey finalized the design and ordered these on October 19th with express shipping.

Juul commented 6 years ago

Version 2 has been ordered