Hi. In this instruction I want to describe how to modify your old 32ch fpv reciver to 40ch with frequency scanner, race band and other cool functions.
First what we need it is fpv video reciver like RC805 or other. In this reciver should be installed proper 5.8 GHz module, like Boscam RX5808.
Next we need some few parts:
Step 1: Open Reciver and Check
First of all we need to open reciver and check did we can modify it or no. It is necessary to take it apart and find the radio module. Almost all chinese FPV recivers build on RX5800 (5808, 5880) radio modules.
Next, gently unsolder a protective metal shield. Under the shield we see a chip, if it RCT6715 is what you need.
Step 2: SPI Mod
To control the receiver using the Arduino, we need to make a slight modification. It is necessary to remove the resistor on 7 chip leg. Just unsolder it, be careful not to hook the elements nearby.
Now return the metal shield back into place. Solder it to board.
Step 3: Arduino Flash
Now lets flash Arduino Pro mini. The simlest way it is use Arduino Nano as flasher to Arduino pro mini. Check wire diagram on picture.
After you prepare, connect your Arduino Nano to PC and launch arduino GUI. Use the attached files with firmware.
In the menu, select the correct port and the Arduino Nano as board.
Then press write.
After the firmware was flashed , disconnect from PC and unsolder wires.
Step 4: Installation
To begin with, lets soldered 5 Way Momentary Push Button. How to arrange the switch depends on where you placed the Arduino.
Let find a place to install the Arduino Pro mini. Attach it to the double-sided tape.
Next make hole for swith.
To control, we no longer need the standard buttons, we need to find the CH1-CH3 contacts on the RX module and cut trace from it. Always check what you do with multimeter.
Next, we need to connect the appropriate contacts from Arduino pro mini to receiver module. Connection diagram see in the picture.
Now lets install OLED display. I was designed case for it. You can download model below. Print case and put LCD into it. Solder wires to LCD. Solder 4 wires to lcd.
In order to accurate place a screen on the case and make holes for the bolts in the right place, print template. I fixed the template by double-sided tape. Cut hole for wires and drill the holes. Srew 3d printed case to reciver. Solde wires from LCD to Arduino using wire diagram.
Now asemble all together.