> For the complete documentation index, see [llms.txt](https://docs.geprc.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.geprc.com/01-getting-started/fpv-basic-conecpts/3.-fpv-glossary.md). # 3. FPV Glossary Entering the FPV hobby feels like learning a new language. We have compiled the most common technical terms, acronyms, and slang used in the drone community to help you get started. {% stepper %} {% step %} ### Purchasing & Kits (Must Read Before Buying) This is the most confusing part for beginners. Choosing the wrong version means you won't be able to fly when you unbox it. | Term | Full Name | Meaning & Explanation | | ------------- | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **RTF** | **Ready To Fly** |

Complete Kit. Includes the drone, radio controller, goggles, batteries, and charger. You can fly immediately after charging.
(GEPRC Example: TinyGO Kit)

| | **BNF** | **Bind And Fly** | **Drone Only (Pre-built).** Includes a fully assembled and tuned drone. **Does NOT include** radio or goggles. You need to provide your own radio and "Bind" it to the drone's receiver before flying. | | **PNP** | **Plug And Play** |

No Receiver Installed.
1. If you use DJI Remote Controller 2 or 3, buy this version to connect directly to the Air Unit.
2. If you use a specific receiver not listed (e.g., a specific Futaba), buy this and solder your own receiver.

| | **ARF** | **Almost Ready to Fly** | **DIY Kit.** Usually includes all parts but requires you to assemble, solder, and tune the drone yourself. | | {% endstep %} | | | {% step %} ### Hardware & Electronics (Specs Guide) | Term | Full Name | Meaning & Explanation | | ------------- | ------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **FC** | **Flight Controller** | The **"Brain"** of the drone. It contains sensors (gyro) and calculates the drone's attitude and flight stability. | | **ESC** | **Electronic Speed Controller** | The component that controls motor speed. Modern drones typically use a **4-in-1 ESC** (four ESCs integrated into one board). | | **Stack** | **Flight Stack** |

Refers to the FC and ESC mounted together in a stack structure.
(GEPRC Example: TAKER F722 Stack)

| | **AIO** | **All In One** |

A board where the FC and ESC are integrated into a single PCB. Common on Whoops and toothpicks to save weight.
(GEPRC Example: TAKER G4 AIO)

| | **VTX** | **Video Transmitter** | Transmits the video feed from the camera to your goggles. Divided into **Analog** and **Digital** (e.g., DJI O3 Air Unit). | | **BEC** | **Battery Elimination Circuit** | A voltage regulator on the FC/ESC. It converts high battery voltage (e.g., 25V) down to 5V or 10V to power the VTX and Camera. **Note:** When using DJI O3, ensure the BEC supports **10V output**. | | **Li-Po** | **Lithium Polymer** | The standard battery type for FPV. High power output but sensitive. **Never over-discharge** (below 3.5V per cell) or it will be permanently damaged. | | {% endstep %} | | | {% step %} ### Flight & Settings (Operations Guide) | Term | Meaning & Explanation | | ---------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **Bind** | The process of pairing your radio controller with the drone's receiver so they can communicate ("Handshake"). | | **FailSafe** |

A safety mechanism triggered when the drone loses radio signal.
1. Drop: Motors stop immediately (Default for Freestyle).
2. GPS Rescue: The drone attempts to fly back to the home point (For Long Range).

| | **OSD** | **On Screen Display.** The flight data text overlaid on your video feed inside the goggles (e.g., Battery Voltage, Timer, Artificial Horizon). | | **Acro Mode** | **Manual Mode / Air Mode.** The standard mode for FPV. The drone **does not auto-level** when you release the sticks. This allows for flips, rolls, and smooth cinematic lines. | | **Angle Mode** | **Self-Leveling Mode.** The drone automatically returns to a flat, level position when you release the sticks. Useful for beginners or emergencies. | | **Turtle Mode** | **Flip Over After Crash.** A feature that reverses two motors to flip the drone back over if it lands upside down. Saves you the walk of shame! | | **Jello** | **Jello Effect.** High-frequency vibrations in the video feed that look like wobbling jelly. Causes: Damaged props, loose screws, or bad PID tuning. | | **PID** | **Proportional-Integral-Derivative.** A control loop mechanism. Tuning PIDs changes how the drone feels and responds. *(GEPRC drones come pre-tuned, so beginners rarely need to touch this).* | | {% endstep %} | | | {% endstepper %} | | {% hint style="info" %} If you messed up your settings in Betaflight and the drone flies weirdly (or won't arm), don't panic! Go to the **"Support / Download Center"** on our official website (`geprc.com`), download the **Factory CLI (Command Line)** file for your specific model, and load it in Betaflight. This will restore the drone to its original factory state. {% endhint %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter: ``` GET https://docs.geprc.com/01-getting-started/fpv-basic-conecpts/3.-fpv-glossary.md?ask=&goal= ``` `ask` is the immediate question: it should be specific, self-contained, and written in natural language. `goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.