Wireless serial USB dongle

With two cheap JDY-40 modules you can easily establish a wireless serial connection without any need for additional configuration or software.

This dongle combines a JDY-40 and a CP2102 USB to serial module. I use it mainly to program my [DPS3005 power supply](https://www.thingiverse.com/thing:6921407), which I equipped with a counterpart JDY-40 module internally. However, you can use the dongle for any other serial connection you would normally establish with a USB-TTY module and serial cable, e.g. for wireless serial output of some (3.3V) Arduino.

**Parts list**

* CP2102 USB to serial module
* JDY-40 wireless serial module (a JDY-41 might work, too, but I haven't tested it)
* 8.7 x 3.7 x 3.7 SPDP switch

The switch is for changing between the JDY-40's AT and serial transmission mode, you'll need it if you use more than one pair of these devices to make them use different channels. For the AT mode, you can use the Arduino IDE's serial monitor, as a dedicated application on Linux, I