What is Analog and Digital FPV VTX Systems?
There are two categories of FPV systems: analog and digital. The signal is what distinguishes digital from analog. A digital system first encodes the wave as ones and zeros before transferring it, whereas an analog system continually changes the wave’s amplitude or frequency.
The most traditional, least expensive, and widely used technology is analog, which operates at 5.8GHz, 2.4GHz, and 1.2/1.3GHz. On the other hand, digital technology is more recent and is becoming more and more popular. It provides better image quality. Digital is anticipated to become widely used soon.
Features of digital FPV system
There are now three 5.8GHz digital FPV systems available for FPV drones; however, since they are all proprietary systems, none of them are cross-compatible. Consequently, unless you have the funds for multiple systems, you must decide which one to choose. For FPV drones, there are now three digital FPV systems available: HDZero, Walksnail, and DJI.
Digital FPV hardware cannot be used with analog equipment. Additionally incompatible with other digital FPV systems are cameras and VTXs made for a particular digital FPV system.
The drone’s video transmitter is the part that wirelessly transfers video from our FPV cameras to our FPV goggles. The VTX’s primary function is to transmit video; it is not dependent on the camera or its settings. All video transmitters are capable of getting the job done, or transmitting video, making them one of the easiest components to purchase.
Feature of analog FPV system
The initial technology that introduced FPV drones was the analog FPV system. Since this decades-old technology is not exclusive to any one business, anyone can develop system components. As a result, it is the system that is most accessible on the market.
The sole FPV option was analog until the middle of 2019. Numerous firms have produced dozens of compatible cameras, video transmitters, and goggles. The most economical way to get started with FPV is with analog. This system is perfect for you if your budget is tight. An further enticing feature of analog video transmitters is their tiny and lightweight design.
Does FPV VTX contribute to image and signal quality?
Image quality
Although VTX costs can vary widely, your FPV camera—not the video transmitter—is mostly responsible for determining visual quality. In most situations, spending more money on a high-end VTX won’t significantly increase visual quality. However, choosing a video transmitter with superior features and dependable signal quality can improve your flying experience in general.
Signal quality
The positioning and quality of the antennas, as well as the VTX’s accuracy in transmitting at the intended frequency, are the primary determinants of the FPV signal’s quality and range.
Higher-end analog VTXs provide cleaner signals that cause less interference to nearby channels and more accurate broadcast frequencies. Antennas ought to be created and tuned for a particular frequency band. Some digital VTXs come equipped with twin antennas (diversity), which you can mount at a 90-degree angle to enhance signal quality independent of the flight attitude of your aircraft.
Power Output
The amount of energy that is radiated through a video transmitter depends on its power output. Milliwatts (mW) or decibel milliwatts (dBm) are units of measurement for VTX output power. For versatility based on your flying environment and preferences, the majority of video transmitters include a programmable output power.
In general, higher power equates to greater range.Typically, 25mW provides enough range for the majority of racing circuits and is great for indoor flying and flying with others. High-power VTXs should be avoided when flying in a group because they can interfere with other pilots’ video feeds and make it challenging to fly together. Pilots must run 25mW VTXs for the majority of racing events.
Recommendation of Best FPV VTX from different FPV system
The following will discuss the ideal VTX for each FPV system, HDZero, Walksnail, DJI and Analog Video Transmitters, in this part according to the various applications.
HDZero
Due to its 1W transmit power, the HDZero Freestyle VTX provides the best range and penetration for HDZero systems. It has substantial heatsinks on both sides for physical protection and cooling, making it perfect for challenging freestyle and long-distance flights.
With a HAM radio license, it may be upgraded to 1W using special firmware; out of the box, it supports 25mW/200mW. The VTX is 28g in weight, supports 2S to 6S batteries (the older version only supported up to 4S), and is compatible with SmartAudio and MSP Canvas Mode.
Walksnail
The Walksnail Avatar HD V2 VTX comes with improved features such an additional 20x20mm mounting option for wider frame compatibility, 32GB storage for onboard 1080p recording, Gyroflow support for image stabilization, a grounded heatsink to reduce GPS interference, and support for Gyroflow image stabilization. Depending on your requirements for image quality, low light performance, or weight reduction, a variety of suitable cameras are available.
Walksnail’s V2 VTX does have certain downsides as a less expensive option to DJI systems, such as the absence of an SD card slot for storage extension and 4K video, and a single antenna design that may affect range and penetration performance.
DJI
The DJI O3 system is an outstanding option for cinematic and freestyle FPV pilots thanks to its exceptional image quality and range. It combines the features of a 4K action camera and an FPV system.
Remember that it DOES NOT SUPPORT THE V1 FPV GOGGLES, BUT ONLY SUPPORTS DJI FPV GOGGLES V2, GOGGLES 2, AND GOGGLES INTEGRA. The O3 camera module is the only camera that is currently available for the O3 Air Unit.
Analog
The 800mW high transmit power VTX, which successfully balances performance and price, is a dependable option for analog.
For builds when there isn’t much room in the FC stack for an additional board, the Rush Ultimate Plus is perfect. However, if necessary, a 30.530.5mm adaptor is also included for mounting on top of your FC. The built-in microphone is a benefit because it enables you to hear the motors and beeper through the audio output of your FPV goggles.
Recommendation of best Analog VTX: HGLRC Zeus Nano VTX
HGLRC Zeus NANO Video Transmitter is ultralight and has multiple mounting patterns, including 16mm, 20mm, and 25.5mm. With a built-in microphone and slim boomerang shape, this VTX brings real-time audio transmission and a wider scope of application for reliable and powerful racing drone motors.
I would recommend the Zeus Nano VTX to anyone looking for a high-quality VTX for their micro FPV drone. It is compact, lightweight, and features a built-in microphone and multiple mounting options. If you are looking for a VTX that will give you great video quality and range, the Zeus Nano VTX is a great option.
Pros of HGLRC Zeus Nano VTX
- Compact and lightweight
- Built-in microphone
- Multiple mounting options
- Up to 350mW of output power
- Smart audio support
Cons of HGLRC Zeus Nano VTX
- Can overheat at high power levels
- Not compatible with all flight controllers
Performance and Features of Zeus Nano VTX
The Zeus Nano VTX is a great choice for micro FPV drones. It is compact, lightweight, and features a built-in microphone and multiple mounting options. If you are looking for a high-quality VTX for your micro FPV drone, the Zeus Nano VTX is a great option.
The Zeus Nano VTX performs well in terms of video quality and range. The built-in microphone is a nice addition, and the multiple mounting options make it easy to install in a variety of frames. The VTX can overheat at high power levels, so it is important to provide adequate airflow.
The Zeus Nano VTX has a number of features that make it a great choice for micro FPV drones. The built-in microphone allows you to hear real-time audio from your drone, which can be helpful for orientation and situational awareness. The multiple mounting options make it easy to install the VTX in a variety of frames. The VTX also supports Smart Audio, which allows you to configure it using your flight controller’s OSD or Betaflight Configurator.
The Zeus Nano VTX is a good value for the price. It is a high-quality VTX that is packed with features. If you are looking for a compact, lightweight, and feature-rich VTX for your micro FPV drone, the Zeus Nano VTX is a great option.
Practical tips for FPV VTX
Avoid Making Contact With the Frame and VTX Antenna Ground
The SMA antenna connector can be mounted directly to some drone frames thanks to a carbon fiber hole in the frame. However, doing so brings the conductive carbon fiber frame into touch with the antenna ground. Your VTX could possibly catch fire if any live wire comes in contact with the carbon fiber frame. In addition, this contact may allow noise to enter the system backward, which may result in a number of problems, including VTX overheating owing to higher resistance.
Never turn on a VTX without an antenna
Never forget to turn on your VTX without an antenna connected. Without an antenna, when you turn on your VTX, there is nowhere for the energy to go, which results in a buildup of heat inside the transmitter. This much heat can harm the video transmitter over time.
Can FPV VTX Work Under Non-Standard Voltage Condition
Our flight controllers come in both HD and analog versions. However, the analog version lacks a stable 10-volt power supply. This poses a challenge when using VTX units that require a 10-volt input to function optimally.
In situations where the flight controller can only provide 5 volts, the VTX can still operate. However, due to the lower voltage supply, the VTX may not achieve its rated power output. For instance, a VTX rated for 500 watts might only deliver around 100 watts under these conditions.
The reduced power output can have significant implications, particularly during longer distance flights. Insufficient power may result in signal loss and video dropout, compromising the quality of the FPV experience
To ensure optimal performance, it’s crucial to match the VTX with a compatible flight controller and ensure that the VTX operates within its specified voltage range. This ensures that the VTX can deliver the necessary power output for reliable video transmission.
When selecting components for your FPV setup, including flight controllers and VTX units, it’s essential to consider voltage compatibility to avoid potential issues with power supply and performance. Here is the video about it.