F4 Brushed Flight Controller (Frsky Rx / No RX)   Update of the F4 Brushed Flight Controller (Frsky Rx + OSD)      Since the firmware is the latest Betaflight 3.4.1, SPI Frsky D16 connection works well in this F4 flight controller.    The position of the BOOT pad on the latest F4 Brushed Flight Controller is changed to near the BIND button.      Note: If you are using EU-LBT firmware radio controller, you might find that you can't bind successfully to F4 Brushless FC. Here are the solutions we provide for you. Thanks to Sebastian Abramowski for giving us the important feedback about binding to EU-LBT firmware radio controller.      Here is a review video made by Mr ShutterBug. (The FC that Mr Shutterbug reviews is the original version, the position of the BOOT pad is different from the latest version)   A smooth and thrilled flying in the forest and detailed explanation of F4 brushed fc.      BETAFPV F4 brushed FC board bring a new era in FPV whoop technology. STM32F411 100MHz high performance MCU, 30A lower resistance MOSFETs, SPI Frsky Rx, Build-in Betaflight OSD and polar reversed protection. All of these is backed by the same reliability and warranty of all BETAFPV FC boards.      High-performance ST Microelectronics ARM Cortex-M4 core F411 100MHz CPU (safely overclocked to 120MHz). Okay, i am the second highest performance whoop board in the world.      30A continuous drain current MOSFET. Lower to 8.5m& 8486; inner resistance value (4.5V). It has a noticeable power improvement in low battery voltage status or with 8x20/8.5x20 motors.      TX1 is available for VTX control. You could change VTX settings such as channel and output power in your Betaflight OSD or using your Taranis LUA Script. Here is the diagram when using the TBS Unify PRO Nano 5.8G VTX.       Polarity reversed connection protection. Battery polar reversed connected. Bomb. This issue will never happens.   Key Features      The world's first compatible BetaFlight OSD, FrSky Rx, BetaFlight firmware, born for acro flight controller for the Micro Whoop or Blade Inductrix quadcopter.    Fully programmable through Betaflight, using the onboard USB port, tune all the parameters, PID's, and rates to your perfect settings    Designed to work with current Tiny Whoop or Blade Inductrix setups    Built in SPI Frsky D16 protocol native receiver, compatible with almost ALL Frsky radios(e.g. Taranis X9D/X9D Plus/X7) or Frsky compatible transmitter module    The flight controller board comes pre-flashed with Betaflight firmware, and pre-soldered 55mm power cable pigtail with JST-PH 2.0 connector, AKA PowerWhoop connector.      Specifications      CPU: STM32F411CEU6    Six-Axis: MPU6000    ESC: All FETs are rated at 30A maximum. Support 6x15mm/7x20mm/8x20mm/8.5x20mm etc motors.    Size: 26mm x 26mm,fully compatible with the Inductrix quad frame and mounting pattern    Firmware version:Betaflight MATEKF411RX 3.4.