DX18

There is an issue with the DX18 radio, It has been burning out the Nano33BLE when attached via PPM. The voltage levels can spike much higher than 3.3v.

The current recommended method to attach a Head Tracker is by adding a Zener diode and resistor to the PPM output pin to clamp any voltages to a maximum of 3.3v.

To attach the DX18, you will need a 3.3v Zener diode and a 100ohm resistor. Here is a Zener that will work from Digikey BZX79-B3V3,113.

The DTQSYS Head Tracker and Recently purchased Tally-Ho Head Tracker by Motionsic have this modification included. Please verify with the supplier before attaching.