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- Felix has been running LowPowerLab since 2011 after a career in software engineering and attending school at ASU.
- While evaluating RF modules, he started with RFM12B, now obsolete
- RFM69
- Also can use RFM95/96 with LPL devices for LoRa projects
- Range for RFM69 is a couple hundred meters to a couple kilometers
- Battery life is about 1-2 years without lots of tweaking to the code
- Moteinos are the main product, they can be customized with modules and flash.
- These are based off the Arduino Uno and use an Microchip (Atmel) 328P for the processing. A newer version uses the SAMD21.
- The power can get down below 10 uA while sleeping, including radios. During transmit, the power is in the 10s of milliamps.
- There is an RFM69 library that gets you started quickly using the RF side of things
- The community has many resources including tutorials and a forum.
- Felix recommends starting with the Mailbox Project which uses the MotionMote kit.
Any thoughts on those $10 Nordic Usb modules? It doesn’t seem to support 900mhz, but does Bluetooth 5/BLE, Thread, Zigbee, 802.15.4, ANT/ANT+, and 2.4GHz..
https://www.nordicsemi.com/eng/Products/nRF52840-Dongle
Those seem to be geared towards BLE, Zigbee and proprietary/802.15.4 protocols, all of which will either not have the range or the low power. They have a very small 2.4ghz PCB antenna which might work OK at short ranges but won’t even come close to sub-ghz fsk modules we discuss in the podcast.
IoT has been a term since before 2000. Although back then it was mostly focused on using passive AND active RFID to transmit data to a local point that parsed it to the net.
Hobbyists weren’t embracing the wireless side in the 90s due to higher cost of modules (which do all the heavy lifting) and lack of low power RF standards.
When the FCC changed the rules so that pre-certified modules eliminated recertification of the end device, modules dropped from ~$50 to ~$15 overnight and hobbyists started to realize “wireless IoT” was easy. It got even cheaper as IC manufacturers pushed the modules into an IC package. Now all hobbyists had to do was follow the datasheet on how to put down the correct traces, antenna, ground plane etc.