Making progress on the design and layout of first J-Box prototype. Decided to keep this first prototype super-simple to make things go faster by using off-the-shelf TI “CC2650 LaunchPad” development kit. Below you can see the board. It has built in 2.5 Ghz antenna (bottom of PCB), along with lots of GPIO ports, a green and red LED, debug chip with micro-USB serial port (upper left) for programming and debugging. It takes either 3V or 5VDC (we’re using 3 VDC).
Here’s the J-Box design below. On the left we see the schematic, along with the Bluetooth Low-energy (BLE) wireless connectivity to my iPhone (it also works with Android). The screenshot shows how to turn a digital I/O on/off using the LaunchPad app. This will enable the prototype J-Box to remain fairly simple at this stage, where the iPhone can be the master remote wireless control.
This first prototype uses batteries instead of RF harvesting to simplify the initial design and remove those variables. Upon successful operation of this prototype, RF harvested power will be integrated in next prototype J-Box.
This is what the components layout of this prototype looks like (before wiring it up). It’s pretty big, but that’s okay for a first prototype built from off-the-shelf components. Making it smaller will come later.
Next steps are to get this all wired up and tested out so it switches the relay using the remote iPhone app. Once that’s working, it will be connected to the new prototype Bat-V Vertical, a 2-band 6m/10m vertical antenna made from aluminum tubing. I will make another post as this progresses.
Feels good to be finally making some headway on building the first prototype. It was quite a lot of research to get to this proof of concept design. Should be interesting to see this come together, followed by integrating the RF power harvesting to power the circuit board and relay without batteries!