ExpressLRS, or ELRS for short, is an open source radio system characterized by its high update rate and low latency. It was developed to offer maximum range with a high update rate, which makes it ideal for applications where a fast response time is crucial. So also when controlling FPV drones.
It competes with the largest radio systems on the market, but is significantly cheaper.
An important feature of ExpressLRS is the concept of the "binding phrase". This is basically a password that is used to pair a transmitter and a receiver. It is important to note that the binding phrase does not have to be a secret, but it should be unique to ensure a secure connection. Devices with a matching binding phrase will connect and synchronize automatically.
ELRS is compatible with OpenTX, a popular open source firmware for RC transmitters. However, it is important to note that an update of OpenTX may be required to use the full functionality of ExpressLRS. Depending on the version, EdgeTX may also work.
The choice between the TBS Crossfire and ExpressLRS systems depends heavily on the user's individual needs and preferences. Both systems have their strengths and weaknesses and there are many factors that should be considered when making a decision.
Team Blacksheep's Crossfire is known for its high-quality components and mature ecosystem. It is an established system with a strong user base and offers high reliability and performance. However, it is more expensive than ExpressLRS and the hardware tends to be slightly larger, which can make it less ideal for smaller builds.
ExpressLRS, on the other hand, is a newer player on the market that has quickly made a name for itself. The system is known for its high refresh rate and low latency, making it ideal for racing and freestyle applications. It is also cheaper than TBS Crossfire and the hardware is generally smaller. It is much more actively developed and offers a wide range of features and customization options. Thanks to the open source approach, you can even contribute your own knowledge to the project.
In addition, more and more manufacturers are bringing ELRS products onto the market. This ensures better availability and you are not dependent on one manufacturer.
Some users report that ExpressLRS can be more difficult to set up than TBS Crossfire, but once set up it is very reliable and powerful. It also has an active community of users who are willing to provide help and support.
Overall, it seems that while TBS Crossfire is prized for its reliability and quality, ExpressLRS is praised for its performance and flexibility. The choice between the two ultimately depends on the user's specific needs and preferences. It is advisable to research both systems thoroughly and consider which one best suits your needs before making a decision.
As already mentioned, ExpressLRS receivers are produced by many different manufacturers thanks to open source. This is good news for FPV pilots. At the same time, however, this also means that there can be variations in quality between manufacturers. For example, an ELRS Nano receiver from manufacturer X may be of better quality than one from manufacturer Y, although both are based on the same foundation.
There are also different names for sometimes very similar receivers, which can be confusing. Basically, ELRS receivers can be divided into three groups:
The best ELRS receivers currently available are
These are among the smallest ELRS receivers on the market and some of them weigh just 0.4 grams! This means they can be stowed in almost any build. The antenna is connected to the receiver via a U.FL connector.
Depending on the manufacturer, they are referred to as EP1 Nano RX, RP1 Nano RX or simply ELRS Nano Receiver.
Popular receivers in this category are the Happymodel EP1 Nano RX, RadioMaster RP1 Nano RX or the ELRS Nano Receiver from BetaFPV.
These ELRS receivers are very similar to those with a detachable antenna, but use a fixed ceramic antenna that is integrated on the circuit board. This makes these receivers even more compact (only slightly higher), as there is no need to lay an antenna cable and therefore no risk of the cable being cut by the propellers. However, the range suffers due to the integrated antenna. According to Joshua Bardwell, these receivers have just over half the range of ELRS receivers with a full-size antenna. However, this is not an obstacle for micro copters in which these receivers would normally be installed. It is better to rely on the small size.
Depending on the manufacturer, these receivers are referred to as EP2 Nano RX, RP2 Nano RX or simply ELRS Lite receivers.
Popular receivers in this category are the Happymodel EP2 Nano RX, RadioMaster RP2 Nano R X or the ELRS Lite Receiver from BetaFPV.
Then there are the ELRS diversity receivers with two antennas. Diversity means that these receivers can switch between the antennas, depending on which antenna receives the stronger signal. This ensures greater safety when flying. Especially in situations where you are pushed to the limit. Of course, these receivers are somewhat larger (but still really small) and two antennas have to be installed. Ideally, one at the front and one at the back of the copter.
Popular receivers in this category are the RadioMaster RP3 Nano RX, the Matek R24-D Nano RX and the EP1 DUAL RX from Happymodel.
A crystal oscillator is normally installed in receivers. However, these oscillators are temperature-sensitive and can change with fluctuations in such a way that they cause failsafes at short distances or can no longer be bound. Especially in extreme situations, for example when flying in extreme heat, this can be problematic. TCXO receivers therefore use an oscillator that is temperature-controlled. This eliminates the problems. Otherwise, these receivers are identical to those without TCXO.
There is already a wide selection of ELRS remote controls and ELRS-compatible remote controls.
The best ELRS remote controls currently available are
These remote controls already have the ELRS system permanently integrated. Of course, there are also ELRS modules that can be used to add ELRS to some other compatible remote controls.
Important: This article is for information purposes only and does not constitute legal advice. We cannot say with certainty what the status of the system is, what is permitted and what is not. All information without guarantee.
