C5VRX: ESP32-C5 analog FPV receiver

Build your own 5.8 GHz analog FPV receiver with an ESP32-C5. Six resistors connected to its GPIO pins make the AV video output. Build it on perfboard, flash the firmware over USB and connect your goggles or monitor.

Experimental receiver — safety & warranty

Video or sync can disappear without warning. Loss of FPV video can lead to a crash, property damage or serious injury. Do not rely on C5VRX as your only means of maintaining safe aircraft control.

Read the flight safety and warranty disclaimer
  • Ground-test every firmware, hardware and settings combination. Remove propellers for bench tests. Check startup, calibration, weak-signal behaviour, video-loss recovery and your actual camera/goggles. Complete calibration before takeoff.
  • Keep disruptive controls on the ground. Calibration, scanning, channel changes, menu entry/exit, DAC tests and diagnostics can interrupt or replace live video. Do not flash firmware or run bench tests during flight.
  • Automatic changes are experimental too. Live filter/profile switching can restart the receive chain and interrupt video. Console A selects report-only mode when switching is disabled; confirm the state with T. Live OUTPUT, format and profile changes restart the pipeline. These settings do not establish flight safety.
  • If you proceed to flight testing, use a controlled area clear of people, traffic and property, keep the aircraft close, and have a safe way to recover control if video disappears. Follow applicable local rules, including visual line-of-sight and observer requirements.
  • A versioned release, “Latest” label or passing CI is not flight qualification. Unmerged PR builds are development builds. Check the exact build’s documented hardware and flight-test evidence; an earlier test does not validate later changes.
  • Report unexpected video loss with the firmware version/commit, hardware, settings, reproduction steps and available logs/DVR footage. Preserve evidence after an incident and investigate on the ground before flying again.

No warranty: the firmware is provided under GPL-3.0-only, including its warranty and liability provisions in sections 15–17, to the extent permitted by applicable law. This warning does not replace those terms or limit rights that cannot legally be excluded.

See the README and the evidence documented for your exact build.

Web flasher & receiver controls

Build details

Drag & drop a firmware binary (.bin) here

or
Legacy builds Archived C5VRX-3 releases. They are no longer developed or rebuilt; C5VRX-5 replaces them. Use Full firmware when switching generations.
Release details
Advanced options

No device connected

Flash log 

          

        

        

          Connection help
          
Use a USB data cable to connect your XIAO ESP32-C5 and choose its serial port when connecting.

          
A running C5VRX-5 receiver enters download mode by itself. If connecting still fails, hold BOOT, tap RESET, then release BOOT.

          
Close the Terminal (or any other serial program) first: only one program can use the port.

        

      


      
      

      

        
What is C5VRX?

        
C5VRX turns an ESP32-C5 into a 5.8 GHz analog FPV video receiver. It is an open-source project by Twotoz and the C5VRX contributors.

        
The basic idea is simple: solder one resistor to each of six GPIO pins, then join the other ends together. That connection is your AV video output for analog goggles or a monitor. Follow the wiring guide below and ground-test your setup.

        
Build and flash an ESP32-C5 FPV receiver

        
Perfboard is the easiest way to build it for now, until a C5VRX DIY kit is available. Start with a Seeed Studio XIAO ESP32-C5 and the six GPIO resistors. Add a 200 Ω resistor from the joined output to GND, and connect your goggles’ or monitor’s video input and ground. The wiring guide shows exactly which pins and resistor values to use. Then install the firmware with the USB web flasher.

        
Open-source firmware and receiver research

        
The C5VRX GitHub repository includes GPL-3.0-only firmware, schematics, host tests and documented experiments. Read the receiver findings for the evidence and limits of each change, or join the project’s Discord from the link above to share builds and test results.

      


      

        
C5VRX DIY kit — in development

        
A DIY receiver board in a Fat Shark-style module form factor, designed to make your C5VRX build easier. These 3D previews show the upcoming kit design. Not available to buy yet. For now, perfboard is the easiest way to build your receiver.

        

          

            Angled 3D preview of the upcoming C5VRX DIY kit board with resistors and a XIAO mounting area
            
Upcoming C5VRX DIY kit · 3D preview

          

          

            Top view of the upcoming C5VRX DIY kit board showing the XIAO mounting area and video, ground and 5 V connections
            
Top view · design in development

          

        

      


      
Hardware for a DIY C5VRX receiver

      
      

        
        
      

      
Affiliate links. As an Amazon Associate, I earn from qualifying purchases. All affiliate earnings go back into C5VRX development.

      

        
Frequently asked questions

        

          What hardware do I need for C5VRX?
          
A Seeed Studio XIAO ESP32-C5, six resistors for the GPIO pins, one 200 Ω resistor to GND, an antenna and a connection to your goggles’ or monitor’s AV input. Perfboard makes assembly easier while we wait for a C5VRX DIY kit. Follow the wiring guide for the pins, resistor values and connections.

        

        

          Does C5VRX receive analog PAL and NTSC FPV video?
          
C5VRX is designed for 5.8 GHz analog FM FPV video and composite PAL/NTSC output. Check the documented camera, goggles and monitor tests for your exact firmware build; compatibility is experimental.

        

        

          Can I flash ESP32-C5 firmware from my browser?
          
Yes. Connect the receiver with a USB data cable and use a desktop browser with Web Serial, such as Chrome or Edge. The web flasher offers published firmware builds and local binary files. The flashing guide also documents the command-line workflow.

        

        

          Is C5VRX qualified for flight?
          
C5VRX is experimental. Passing tests or installing a versioned release does not establish flight safety or guarantee range. Read the safety and warranty disclaimer, complete calibration and ground-test every firmware and hardware/settings combination.