ELRS tuner 915Mhz-nano version

This project refers to the PCB design drawing of Mr. Wang Hai. The power can be turned up to 1W. It requires independent power supply, fan and heat sink. The maximum power is 1W.
Find EXPRESSLRS_PCB_RX_V3 in targets.h and add a line #define GPIO_PIN_FAN_EN 16 in userdefines. High power must also be enabled to take effect.
Since the E19 module is out of supply, we can only design towards E32.
Open source address: https://github.com/ExpressLRS
software reference: https://www.bilibili.com/video/BV1v34y187Za
2022.8. 8
The 1.2 version has been optimized, the boot button position has been changed,
the fan connection port has been changed to multi-layer, the resistor and capacitance position next to 2028 has been adjusted, the E32 and voltage regulator board have been lowered
2022.8.11
The 2.0 version has been optimized, and the ESP32 is placed By adding the above, you can make the E32 antenna position closer to the antenna hole, use shorter adapter cables to reduce losses, and the wiring becomes longer.
Add a PH2.0 horizontal plug interface, which can use additional power supply. You need to change the printout. The shell
schematic diagram is different from the PCB, which does not affect
the success of the test on August 5, 2022.