How to Setup ExpressLRS 2.4GHz

ELRS Firmware Flashing, Receiver/FC Wiring and Betaflight Configuration

by Oscar
Published: Last Updated on
setup expresslrs 2.4ghz tutorial

ExpressLRS is an affordable open source RC system that offers ultra low latency and long range. In this tutorial I will show you how to setup ExpressLRS 2.4GHz transmitter module and receiver on OpenTX/EdgeTX radio and Betaflight, and how to flash/update the latest ELRS firmware.

New to ExpressLRS? This article explains the advantages of ExpressLRS over other radio control systems and why I prefer to use 2.4GHz than 900MHz.

ExpressLRS 2.4GHz Hardware Selection

All transmitters and receivers with ExpressLRS firmware are compatible regardless the brand.

Transmitter Module

There are so many options when it comes to transmitter module, it might seem difficult to choose. But really, they all have similar performance because they are all based on the same open source design by the ExpressLRS. The main difference is the build quality and certain features. I recommend getting one from a well established brand.

Full Size Module (JR)
Happymodel ESTX24 Pro TX BetaFPV ELRS Micro TX AxisFlying Thor
Happymodel Es24tx Pro 2.4ghz 1000mw 1w Expresslrs Elrs Micro Tx Module Betafpv Expresslrs Elrs Micro Tx Module Jr Bay Tx16s
Banggood
GetFPV
RDQ
BetaFPV
Banggood
Banggood
GetFPV

Other full size module options:

Lite Module
Happymodel ESTX24-Lite TX BetaFPV ELRS Nano TX  Jumper AION
Betafpv Expresslrs Nano Tx Module Jr Bay Tx16s Jumper Elrs Nano Aion Expresslrs Tx Module
RDQ
Banggood
AliExpress
BetaFPV
Banggood
RDQ

Other lite module options:

The TX module plugs into the external JR module bay, and it’s compatible with radios such as Radiomaster TX16S, Jumper T16, and Frsky X9D+. For smaller radios such as the Jumper T-Lite and TBS Tango 2, you will need the “Lite style” module as the module bay is smaller.

Betafpv Expresslrs Elrs Micro Tx Module Display Screen


TX Antenna Upgrades

Stock antenna works fine, but if you are trying to push range you can try these higher gain antennas:

HappyModel Moxon Namimno Black Pearl Loop BetaFPV Moxon
Happymodel Moxon 2 4g Expresslrs Elrs Antenna Namimno Expresslrs Elrs 2 4ghz Flash Black Pearl Loop Antenna Black Betafpv Moxon Antenna Expresslrs Elrs
Banggood
GetFPV
RDQ
Banggood BetaFPV
VAS Diamond TrueRC True-MOX Turbowing Fishbone
GetFPV
RDQ
GetFPV
RDQ
Banggood

Receivers

BetaFPV Nano RX BetaFPV Lite RX Flywoo ELRS RX
Betafpv Expresslrs Nano Rx Close Up Betafpv Expresslrs Elrs Lite Rx Radio Receiver Flywoo 2.4ghz Expresslrs Elrs El24e Rx Antenna
BetaFPV
Banggood
Banggood
BetaFPV
RDQ
Banggood
Happymodel EP1 Happymodel EP2 Happymodel PP
RDQ
Banggood
AliExpress
Banggood
AliExpress
RDQ
GetFPV
AliExpress

Other receiver options:

All the ExpressLRS receivers and transmitter modules are cross-compatible, so it doesn’t matter which brand you get your hardware from they will work together. They are all based on the same ELRS open source design, the main differences between these receivers are:

  • Build quality
  • Size
  • WiFi Support (for firmware update and configuration)
  • Antenna (some have built-in low profile ceramic antenna, while some comes with U.FL connector for longer external antenna)

Size comparison to TBS Crossfire Nano and Frsky R-XSR:

happymodel expresslrs ep1 ep2 pp crossfire nano frsky r-xsr receiver size comparison

Size comparison: Frsky R-XSR, Crossfire Nano, EP1, EP2, PP

Should I Update ExpressLRS Firmware?

You should flash the latest firmware to both of your ELRS TX module and RX whenever possible. ExpressLRS is a fast evolving project, every firmware update includes many bug fixes and improvements. Keeping up with the latest version will protect you from potential issues and give you the best possible performance.

There are options to how you want to use ExpressLRS, and some of those options can only be set when you flash firmware.

Also when you bind the receiver and transmitter you don’t necessarily know they have the compatible firmware on them. You can find out what firmware version you are on when you run ExpressLRS LUA script.

ELRS firmware version number is in this format: AA.BB.CC

  • AA: major version number
  • BB: minor version number
  • CC: patch number

All releases with the same major version number are cross-compatible, e.g. 2.0 will work with 2.1, 2.2, 2.5 etc. But V1 firmware won’t bind with V2. Major version number will only get incremented when there is a breaking change. You should update if you want to make use of a new feature, target, or bug fix. If a new version contains a critical bugfix that will be communicated in the release, in which case you should update regardless.


Flash EdgeTX

EdgeTX is a fork of OpenTX, it’s “kind of experimental” but is more advanced and has a lot more new features than OpenTX. It also has some benefits when used with ExpressLRS such as 500Hz gimbal polling. Check out why and how to flash EdgeTX.

Flash Latest OpenTX

If you decided to flash EdgeTX, you don’t need to worry about OpenTX and just can skip this part. But if you still want to stick with OpenTX, you need to update OpenTX to the latest version following these steps.

If your OpenTX version is older than 2.3.12, then you will need to flash the latest OpenTX.

Updating OpenTX firmware on your radio allows you to flash the ELRS firmware to the transmitter module from the radio, and get CRSFShot working.

Here is a step by step guide on how to flash OpenTX. Anyway I will try to summarize the steps here.

Get the latest OpenTX Companion, you will need 2.3.12 or newer (just get the latest one): http://www.open-tx.org/downloads

Install OpenTx Companion on your computer, and run it.

Go to Edit Settings, and select the options you want. I explained these options in my step by step guide.

Make sure you have Release (stable) selected in Release Channel so you are not downloading the Nightly build.

Click the “Download” button on the left, and click “Check for updates” on the pop up window, “Latest Download Version 2.3.xx” should appear. Download firmware and save it somewhere.

Put your radio in bootloader mode.

Click on the button “Flash firmware to radio” on the sidebar, load the firmware we just downloaded and click “Write to TX“.

When flashing is done, unplug USB cable and restart your radio.

If you also get an “SD card content” warning, you should download the new SD Card content here (find the link for your radio, and get the latest file): https://downloads.open-tx.org/2.3/release/sdcard/

Make a backup of your current SD card content first.

Once downloaded the SD card content, plug in the USB cable to your TX16S, and select “USB Storage” to access the SD card inside the radio (or you can just take it out of the radio). Copy the files over to your SD card. If you don’t see the prompted window when you plug in the USB cable, See this post, you should sett that option to “ASK”.


Identify Your Hardware

There are many manufacturers making receivers and transmitter modules for ExpressLRS.

You need to know the brand and model of the hardware you are using before flashing firmware to them. Flashing the wrong firmware might not end well.

If you don’t know which brand and model of your hardware, simply enable WiFi hotspot mode and find out there.

  • To do this on the transmitter module, go to the ExpressLRS LUA script, WiFi Connectivity and enable WiFi.
  • To do this on the receiver, simply wait 60 seconds without turning on your transmitter, it will go into WiFi mode automatically.

On your laptop, you should see a WiFi network called ExpressLRS TX or RX, connect to it, the password is expresslrs. After  connecting, go to your browser and type 10.0.0.1 in the address bar, it will open up a website which will tell you which firmware target it’s using.


Install ExpressLRS Configurator

ExpressLRS Configurator allows you to build, compile and flash firmware for the receivers and transmitter module.

Download it here: https://github.com/ExpressLRS/ExpressLRS-Configurator/releases

For Windows, click the link with this name: ExpressLRS-Configurator-Setup-X.X.X.exe

Once you installed ExpressLRS Configurator, you will get prompted to update whenever there’s a new version, and it downloads and installs it for you automatically which is handy.

Your computer has to be connected to the internet when using the Configurator.


Download ExpressLRS LUA Script

A lua script is a mini program on your radio.

The ExpressLRS LUA script allows you to change radio link settings, enter binding mode, enable WiFi etc.

You can check if your radio has already had the ExpressLRS LUA script installed by going to TOOLS (long press the SYS key). Note that there are currently two ExpressLRS LUA scripts avaialble. The one named “ELRS” is for ExpressLRS V1, the one named “ExpressLRS” is for the latest V2 firmware, which is what we need here.

If you can’t find it, you can download and install it. I will show you how.

You can download it in the Configurator by selecting release version and target, and a download button will appear.

Expresslrs Elrs Configurator Download Lua Script V2 Before Flash

The downloaded file should have “.lua” file extension, put that file in this directory on your radio’s SD card: \SCRIPTS\TOOLS\


Compile and Flash TX Firmware

You can flash the TX module using one of these methods:

  • UART/USB
  • WiFi

I found WiFi to be the easier method, I will demonstrate how to do it here.

Building ELRS TX Firmware

Use the ExpressLRS Configurator to build the firmware for your TX module.

Expresslrs Elrs Configurator V2.5 Flash Build Tx Firmware

Under Releases, choose the latest firmware.

Under Device Target, select the brand, and device. In this example, I have the BetaFPV Micro 1000mW TX, so the Target Device selections would be:

  • Device Category: BetaFPV 2.4 GHz
  • Device: BetaFPV 2400 TX Micro 1000mW

Let me explain what some of the settings mean.

Regulatory Domains – depending on where you are, the second option “EU_CE” is for people in the EU, anywhere else please select the first option “ISM”.

BINDING PHRASE – it’s like the key to your car, be creative and make a unique phrase, so people you fly with don’t accidentally use the same phrase and cause problems. Note that other people CAN control your drone if they use the same binding phrase.

NO_SYNC_ON_ARM: Racing = Enable; Long Range = Disable; Not sure? Just disable it.

Network => Auto WiFi On Interval: how many seconds it turns on WiFi mode if no radio link is established. Default is 60 but I personally prefer to set it to 20. If the receiver goes into WiFi mode you just need to unplug LiPo and plug in again.

Network => HOME_WIFI: See here for more detail.

The Configurator remembers your options, so you don’t need to select them again next time.

Flash TX Firmware via WiFI

In the ExpressLRS Configurator, under Flashing method, select WiFi.

When you are ready, click the BUILD button (NOT Build and Flash).

The first time you flash will take 5 to 10 mins depending on your internet speed as it needs to download quite a lot of stuff. But it gets faster the next time you flash.

After the configurator finishes building, a windows should pop up containing the firmware files, one named “firmware.bin” and the other named after the module type you selected. The two files are identical (just different names), so you can use either one to flash your TX module.

Expresslrs Firmware Compile File

Plug in the TX module to your radio module bay and power on radio.

Betafpv Expresslrs Elrs Micro Tx Module Jr Bay Tx16s

On your radio, setup a new model profile, in Model Setup, enable External RF and select CRSF in Mode.

Go to System settings => Tools, and select ExpressLRS (it’s for V2 firmware, ELRS is for V1 firmware). This is the LUA script we downloaded earlier.

Expresslrs Elrs Lua Script V2 Radio Tx16s Edgetx

Select “WiFi Connectivity“.

Expresslrs Elrs Lua Script V2 Interface App

Select “Enable WiFi” and leave the radio powered on.

Expresslrs Elrs Lua Script V2 Wifi

Go to your computer’s WiFi, you should find a new network called “ExpressLRS TX Module“. The WiFi password is: expresslrs

Open browser and go to 10.0.0.1

Click “Choose File” and select “firmware.bin” generated from the ExpressLRS Configurator earlier.

Click Update. That’s it!

Flash TX Firmware via UART/USB

My favourite way to flash is using WiFi, but if your computer doesn’t have WiFi, you can use the USB port on the TX module to flash.

Plug in the USB cable to the TX module, a new COM port should appear on your computer.

In the ExpressLRS Configurator, under Flashing method, select UART. When you are ready, click the BUILD and FLASH button (not Build). The flashing will take a few minutes.

I found the BetaFPV TX module to be plug and play when flashing via USB. However with the Happymodel TX module, it requires an extra step for UART flashing to work. On the TX module board, there are 6 jumpers, by the default the middle two are bridged. When flashing via USB/UART, you should move the jumpers down to the bottom two pins.

Also make sure to install the cp210x drivers if you haven’t already.


Connect ELRS Receiver to FC

Here’s the pin-out of the PP, EP1 and EP2 receivers.

Connect TX and RX pins to any spare UART on your flight controller. DO NOT use soft-serial because it’s too slow.

Connect TX to RX, and RX to TX.

Here’s the pinout for the BetaFPV ELRS Nano RX.

Betafpv Expresslrs Nano Rx Close Up

Build and Flash RX Firmware

For receivers with WiFi built-in, you can flash firmware via WiFi, just like flashing the TX. But personally I found using Betaflight Passthrough easier for flashing RX, and I will demonstrate it here.

Open ExpressLRS Configurator, select the latest firmware release, and choose the device target based on the brand and receiver type. For example:

  • For PP receiver, the Device is: HappyModel PP 2400 RX
  • For EP1 and EP2 receivers, the Device is: HappyModel EP 2400 RX

Make sure to set the binding phrase as your TX, your RX will just bind with the TX automatically after flashing firmware. If you don’t set a binding phrase, you can bind it manually as described here.

Expresslrs Elrs Configurator V2.5 Flash Build Rx Firmware

Flash RX Firmware via Betaflight Passthrough

Before proceeding, make sure to configure Betaflight first as described in this section.

Now connect the USB cable to your quad to power the FC and RX.

In ExpressLRS Configurator, choose the COM port of the FC (if not sure, check the COM port in Betaflight Configurator, but remember to disconnect/close it afterwards).

Hit BUILD & FLASH. It will take a couple of minutes.

Flash RX Firmware via WiFi

Basically the steps are the same as flashing the TX module via WiFi.

In the ExpressLRS Configurator, hit BUILD and it will take a couple of minutes to compile firmware.bin.

By default, if you power the EP1 and EP2 without turning on the radio, after 20 seconds it will enter WiFi mode (LED will be flashing rapidly to indicate that). The RX’s WiFi signal is a bit weak so place the RX closer to the WiFi antenna to your PC.

Connect to the WiFi network “ExpressLRS RX“. The WiFi password is: expresslrs

Go to 10.0.0.1 in your browser, and upload the firmware file.

Flash RX Firmware via UART

In the rare event, if neither of the above methods work, you can try UART flashing as described here.

Flashing RX via FDTI

If for whatever reason you bricked your RX, which could happen if you lost power or connection during flashing, you can bring it back by flashing via FDTI: https://www.expresslrs.org/2.0/quick-start/receivers/hmep2400/#flashing-via-ftdi.


Binding Receiver

If you’ve set the Binding Phrase when flashing both TX and RX, you shouldn’t have to do anything, because they just automatically bind. When binding is successful, the status LED on the RX should stay solid.

If you didn’t set a Binding Phrase, you can manually bind your RX to the TX following these steps:

Bind procedure:

  1. Power on receiver, wait until the LED on the RX is off, immediately turn off the power, and then repeat again the above steps. When the RX is powered on for the third time, the LED will start to double-flash, indicating the RX is in binding mode
  2. Plug in the ELRS TX module to your radio, and enable External RF and select CRSF protocol in Mode. Execute the ELRS lua script in System Settings, Tools. Select [Bind], the LED on the RX module will become solid if bind successfully

Receiver status LED meanings:

  • Solid LED means bind successfully or connection established
  • Double-flash means it’s in bind mode
  • Flash slowly means waiting for TX module connection
  • Flash fast means it’s in WIFI hotspot mode, you can connect to the RX’s WiFi network to upgrade RX firmware by visiting 10.0.0.1 in your browser (password: expresslrs)

If the receiver doesn’t enter bind mode, chances are you flashed the receiver WITH a binding phrase. Try to flash RX firmware again with binding phrase disabled.

When the receiver and transmitter are bound, you should see a “C” in the top right corner in the LUA script when you power them on. However when they are powered off or not bound, you will get a ““.


Betaflight Setup for ExpressLRS Receiver

To setup ExpressLRS RX’s:

Go to the “Ports” tab in the Betaflight configurator, and enable “Serial RX” for the UART you’ve connected the ELRS receiver to. Press “Save”.

In the Receiver tab, under the “Receiver” Section, select “Serial-based receiver“, and select “CRSF” in the second option. Click Save.

Setup Betaflight Receiver Protocol CrsfIn Configuration tab, Enable “Telemetry” feature. Click “Save”.

Setup Betaflight Configuration Feature Telemetry

Your RX should be working now.

To verify, go to the “Receiver” tab, you should see response from stick movement. If the channels are in the wrong order, just try a different “Channel Map”.

Check if end points (1000 or lightly lower / 2000 or lightly higher) and mid points (1500) are correct, see this guide on how to adjust if they aren’t correct.

To make sure Telemetry is working, go to the Telemetry page in the radio, and select option “Delete all sensors”, then “Discover new sensors”.

Asterisk flashing means telemetry is updating.

expresslrs telemetry opentx

In Modes tab, you should set AUX 1 as your arm switch (note that it’s now a 2-position switch).


Display LQ and RSSI in OSD

Further Reading: What are LQ and RSSI?

In a nutshell:

  • RSSI – Signal strength, how loud the signal is (value from -130dBm to 0dBm)
  • LQ – Link Quality, how well your receiver can understand the signal (value from 100% to 0%)

Both indicators are useful, but if you have to pick one, LQ is probably more important.

To display LQ properly you should use Betaflight 4.2 or newer, where they introduced a new RFMD:LQ% format for the LQ OSD element.

  • Configuration tab, Disable RSSI_ADC
  • Receiver tab, set RSSI Channel to Disable
  • OSD tab, enable Link Quality and RSSI in dBm

It’s useful to have both measurements. For example:

  • low LQ, high RSSI = lots of interference around you
  • high LQ, low RSSI = you are very far away and should be cautious, or if you are close that’s an indicator that maybe something is wrong with your antennas
  • low LQ, low RSSI = reaching the range limit of your gear

Setup Failsafe

Digital protocols typically have a failsafe flag in the data packet, so setting “no pulse” in the radio might not actually mean anything (though it won’t hurt to set it). So set it up in Betaflight Failsafe tab.

Make sure to do a props-off failsafe test just to verify that failsafe is actually working (remove all propellers, arm the quad and turn off radio, be ready to unplug if anything goes wrong).


ELRS LUA Script Settings

There are 3 major settings in ExpressLRS Lua script: Packet Rate), Telem Ratio (telemetry ratio) and TX Power.

Expresslrs Elrs Lua Script V2 Interface App

TX Power

Almost all modules support 250mW, some even up to 1W. Tests showed that 100mW can do 33km range with stock 2.4GHz gear. And it would most likely outperform your 5.8GHz video link anyway. Higher power will also consume more current, and reduce your radio battery life significantly. Higher than 500mW usually requires an external battery plugged into the module. A fan/additional cooling is recommended for higher than 250mW.

By enabling the option Dynamic Power, allows the system to automatically adjust output power depending on LQ and RSSI, this can potentially save battery life. However to do this you must have telemetry enabled.

Packet Rate

Packet rate is a compromise of range and latency, you just can’t have both. Higher packet rate has lower latency, but less range.

Most of the times I fly within 1km, so I prefer to use the highest packet rate available to my TX16S, which is 500Hz. Note that 500Hz is not available in some radios, for example the Tango 2 only supports up to 250Hz.

Telem Ratio

Telemetry Ratio is how often telemetry data get sent. The larger number means slower telemetry update, e.g. 1:8 means telemetry data is sent every 8 frames, while 1:128 is every 128 frames.

More frequent telemetry will increase latency to the control link, but less telemetry is more likely to give you telemetry lost warning. And it depends on your requirement too, if you want more frequent telemetry updates then you would want to set a smaller number. You can turn it off completely for the most consistent packet rate.

If you get “Telemetry lost” warnings while your link quality is still looking good, it could be that your telemetry rate is too low. Try increasing Telem Ratio one step at a time until the “Telemetry Lost” warning disappears.

Switch Mode

The Switch Mode setting controls how the channels AUX1-AUX8 (channel 5 to 12) are sent to the receiver (the first 4 main channels are always 10-bit). The options are Hybrid & Wide.

With Hybrid mode, most of your channels will only be 2- or 3-position, this is done to reduce latency.

The “Wide” option makes your channels 64- or 128-position which is more than enough for most things we want to do, and that’s what I recommend to use.

Note that AUX1 (channel 5) is always 2-position, which is dedicated for arming. Low position (1000) for disarming and High position (2000) for arming, you should set it up like this in Betaflight or you could run into problem with ExpressLRS.


Additional Receiver Settings

There are more settings when you connect to the receiver via WiFi (on the page where you flash RX firmware).

First, power on the receiver and wait until it goes into WiFi hotspot mode. It does it automatically after being powered for 60 seconds by default (LED flashing rapidly when it’s in WiFi mode). Or you can also force the receiver to go into WiFi mode in the radio’s LUA script.

Now, connect to the WiFi network (the WiFi password is: expresslrs). In your browser, go to 10.0.0.1

On this page, scroll down and you will find the additional settings like Model Match. For PWM receivers, you will also have settings like PWM Output and Failsafe Positions for each channel, and the option to invert the channel outputs. These setting are not yet available in the LUA script.


Performance Enhancement Settings

These settings might make your quad fly more locked in. Give them a try anyway. Backup original settings in case you want to go back.

Turn off ADC filtering in radio (System Settings, Hardware).

Enable 500Hz mode in ELRS LUA script.

In Betaflight CLI:

  • set ff_interpolate_sp = on
  • set ff_smooth_factor = 37
  • save

In Receiver tab, RC Smoothing, set:

  • Smoothing Type to Interpolation
  • RC Interpolation to Manual
  • RC Interpolation Interval to 5ms (500Hz), or 10ms (250Hz)

Adding Home WiFi Network

It makes it much easier to flash firmware when you setup “Home WiFi Network” in ExpressLRS. When you put your ELRS transmitter module or receiver in WiFi mode, it will connect automatically to your home WiFi network, then you would be able to flash firmware on a browser from your computer. Easy!

To set it up, you first need to flash your TX module and RX with “HOME_WIFI_SSID” and “HOME_WIFI_PASSWORD”. These are your home WiFi network name and password. Even if you are already on the latest firmware, you have to re-flash to let your transmitter module and receiver know your network login for this to work.

Expresslrs Elrs Configurator V2.5 Home Wifi Network Ssid Password

Once that’s done, you can turn on WiFi mode. You can do this in the LUA script.

Expresslrs Elrs Lua Script V2 Wifi

Open ExpressLRS Configurator, and it will automatically detect your ELRS device. Click on DNS (elrs_tx.local or elrs_rx.local), or the IP address (192.168.0.XXX), if it doesn’t work just try the other, one of them should work.

This will bring you to the page to upload the firmware, same as flashing using the WiFi method we covered before.

Expresslrs Elrs Configurator V2.5 Home Wifi Network Dns Ip


FAQ

LUA script only shows “Connecting…”

That’s an indication of the ExpressLRS TX module is not talking to the LUA script

Possible causes of the problem:

  • TX Module is installed, or is installed incorrectly (pins in the module bay are not making proper contact or broken)
  • Maybe the TX module is in WiFi update mode, restart the radio and try again
  • Make sure you have set RF protocol to CRSF
  • If you are running OpenTX, make sure the version is not too old (it has to be 2.3.12 or after)

How to Install Cooling Fan

There is no fan plug for the Happymodel 2.4GHZ TX module, you need to solder it directly. I found 3.3V and GND at this capacitor. Make sure you confirm voltage with a multimeter before connecting to avoid damaging the board.

Happymodel Expresslrs Elrs 2.4ghz Tx Module 3.3v Fan SolderI am using a 20x20x6mm 5v fan which fits perfectly in their new module cover. The fan can be bought on Amazon (affiliate link): https://amzn.to/3ixZpE0. The fan should act as an exhaust and take the hot air out, not blowing onto the PCB to avoid dust building up inside the module. Current draw is quite low so that shouldn’t be an issue. At 5V, 0.05A.

Happymodel Elrs 2.4ghz Tx Module Fan Solder

Inconsistent Packet Rate – CRSFShot Not Working

In the ELRS lua script top bar, there is an indicator (e.g. 0:200) which tells you how many packets per second it’s getting from the radio. You can use it to confirm the consistency of the RC link.

Expresslrs Elrs Lua Script V2 Interface App

Ideally it should always show a stable number that is the same as the packet rate you select. For example: 0:50, 0:150, 0:250, 0:500.

If it shows an inconsistent number like 0:63, or is stuck at 0:250 at every packet rate you select, then your radio does not have CRSFShot working properly.

The latest official release of OpenTX (2.3.12 or newer) already includes CRSFShot, so double check if your OpenTX version is outdated.

Using ExpressLRS Logo as Model Image

I made a logo you can use as model image in the TX16S/T16. You can learn how to use it here.

Image download: google drive.

Install USB to UART Driver

You might or might not need to install this driver on your PC if you want to update your TX via UART: https://www.silabs.com/developers/usb-to-uart-bridge-vcp-drivers

Taranis QX7

For Taranis QX7 users, if you are running OpenTX, you’ll need to perform this mod in order to run 400k baud rate on your radio. It’s not needed, but it is recommended if you want to get the most out of ELRS: https://www.youtube.com/watch?v=mHfQe05XJn8&ab_channel=edrone

If you run EdgeTX you won’t need to do this mod as the bug has been addressed in software.

Betaflight LUA Script Support

ELRS does support Betaflight Lua script, all you need to do is to enable the “ENABLE_TELEMETRY” option when compiling/flashing firmware.

Official Documentation

For more detailed explanation of the system, visit ExpressLRS official wiki, I barely scratched the surface here: https://github.com/

Edit History

  • Jun 2021 – Updated guide: OpenTX 2.3.12 has been released, no longer need to flash nightly
  • Jul 2021 – Updated: ExpressLRS 1.0 official release
  • Aug 2021 – Added info for BetaFPV ELRS Nano TX and RX
  • Nov 2021 – Updated product list
  • Feb 2022 – Updated the complete TX, RX and antenna options currently available on the market
  • May 2022 – Updated instructions for version 2.5, added info about adding home network, updated screenshot of LUA script (V2)

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104 comments

Bad Raven 8th May 2022 - 9:01 pm

I have three quads running on ELRS now, but am confused by the LUA on my FrSky X12S Horus. It seems to take forever to run, though it does in the end complete, and the quads bind and run.

Reply
Felix Max 5th May 2022 - 12:45 pm

Hello Oscar, thank you so much!
Can you tell us how to set to (Radiomaster Tx16S) a telemetry setup warning etc?
Like on what RSSI etc. you should get worried to not failsafe etc….
i have found something like that once for Crossfire but i switch completly to ELRS so that would be great!
Thank you so much for all your work!

Reply
Johnny 25th April 2022 - 4:34 pm

I see there is now a HappyModel ELRS PWM receiver module. Any difference in setting that one up?

Reply
Oscar 25th April 2022 - 6:25 pm

Same thing.

Reply
Badfrog 20th April 2022 - 8:21 am

Thanks for your info. My TX16S max v2 is on order and I just received my ELRS module. Looking forward to getting it all working and this guide will be invaluable.

Reply
Dave 13th April 2022 - 1:39 am

Just FYI, the happy model version of the elrs module seems to have a JST plug for a 5v fan on the board – no need to go off the resistors.

Reply
David Pulvermacher 12th April 2022 - 9:15 am

Brilliant, clear and concise instructions Oscar. Thanks you!

Reply
socalrcguy 10th April 2022 - 3:59 am

What is the current draw at 1000mw, 500mw, 250mw, and 100mw? You mentioned that it is only 50ma but at which power level? Thanks!

Reply
Eric 27th March 2022 - 9:53 am

Hi Oscar, I followed your steps in setting up my Jumper T-Pro TX. When I reached the step on performing a BootLoader on my TX; I could not locate the right buttons on my Jumper T-Pro. Wonder if you could advise. Thanks a million.

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Oscar 27th March 2022 - 11:41 am

if you type in “jumper t-pro bootloader mode” you will find a ton of tutorial on how to do this :)

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Andre 13th March 2022 - 5:05 pm

Can anyone help me out I’ve installed elrs beta fpv 2.4 on my 5 inch with the jbf7 and a succex 45a esc with a tx16s everything works great until I try and do punch outs at full throttle I get rx loss for about a second and then the signal comes back and if I keep the throttle at 100% the signal doesn’t come back and it just falls out of the sky. I’ve tried switching 5v regulators ground wires and tried changing the uart. I’ve got a capacitor on it 1000mf. I have also tried moving the receiver to different places with no luck

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pianowow 9th March 2022 - 5:10 am

If you have a module with ELRS 1.x installed, you need the 1.x version of the LUA script. You can use it to install the latest firmware, then install the v2 LUA script.

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yannick Colin 7th March 2022 - 7:00 am

hello there… is it possible tu use an elrs rx on silverware lite 2s?
best regards

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NeueAuteur47 19th February 2022 - 11:42 pm

Thanks Oscar, very helpful!
I am having trouble flashing my RX/TX via the Express LRS configurator. When I get to the Build and Flash stage, I get an error message stating that my Mac is using an outdated version of Python (??), that I need to have Python 3 installed. I’ve tried to upgrade Python but have been unsuccessful with my older Mac OS. What should be my next move?

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Oscar 20th February 2022 - 11:13 am

i am not sure as i am not a Mac user, can you use something like Virtual Machine or Wine and run Windows on it?

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NeueAuteur47 21st February 2022 - 8:40 pm

Will try. Thanks Oscar for the reply.

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Neil 8th February 2022 - 10:19 pm

As always Oscar nice tutorial! but I would love to see how you setup your ELRS telemetry widgets please share a link if you already have done this.

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Paravy 7th February 2022 - 11:12 pm

Merci pour ce guide qui m’a été très utile pour flasher mon betafpc micro TX 1000mw ,flashe en 2.2.0

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Dan Lahrman 6th February 2022 - 12:56 am

I am running TX16S with 2.3.14. I am unable to get the expresslrs Lua to work. It just shows “connecting” and all question marks. I did find that I am able to use the elrs module if I use the crossfire setup Lua.
For those having similar issues to me give the crossfire Lua a try

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chris thompson 13th January 2022 - 6:27 am

Hi Oscar
For 500hz, in 4.3 feedforward averaging should be set to 2_point, feedforward_smoothing to 65, and jitter reduction of 5.
For 250hz, in 4.3 feedforward averaging should be set to 2_point, feedforward_smoothing to 45, and jitter reduction to 6.

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Vince 12th January 2022 - 1:00 am

I’m running OpenTX 2.3.14. I installed the Lua Scripts as instructed and as soon as I did, all my models were deleted. When I tried “executing” the Lua, like BS below all I get is a loading screen.

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byMarto 20th February 2022 - 4:39 pm

Same here,… how did you pass the step with the infinite loading ?

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zac 6th January 2022 - 6:16 am

Had a question ..
When we use two radios and intend to fly a model / quad that has an ELRS receiver installed , is it possible to bind both radios as long as we use two separate ELRS TX modules installed on each radio ?
On the Frsky R-XSR this was possible by using TX cloning method . Is this possible or straightforward for ELRS ?

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BS 6th January 2022 - 1:50 am

I’ve had 2.3.14 loaded on my TX16S running FrSky and just got the HappyModel ELRS24 module. Two weird issues. When I select “noheli” in the build options and flash the TX, it will not boot. If I build without that selected the TX will boot. For now leaving that unchecked.

When I go to SYS > TOOLS on the TX and select ExpressLRS all I get is a loading screen and nothing appears. I’ve left it for quite a while and the module is not loading. Any thoughts?

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Manuel Bonow 4th January 2022 - 7:03 pm

If that’s the same Aio that resides in Tina whoop and c25, you can hook up a hm ep Rx the way you explained/ identically to crossfire.
That is for elrs 1.0.2.
For other brand receivers and other firmwares this might not be possible.
Ideal way is a set of full uarts where no inverted pads or sbus are used on)split off.
So you might need to change wiring so you take the UART that is controlling your VTX now.

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Alejandro 29th December 2021 - 10:56 pm

i go into tools on my radiomaster tx12 and i only have spektrum there, and i updated my open tx to the newest version what did i do wrong?? please ive been at this for over 4 hours

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John Cushard 28th December 2021 - 1:38 am

followed things step by step …. 3 times … I get telemetry just fine, but no response in radio setting in betaflight …enough to drive an old man over the edge … any ideas ??

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gianpz 11th January 2022 - 3:24 pm

Hi, have you solved your problem? the same thing happens to me using literadio 2 elrs, binding happens but I have no answer in the betaflight receiver tab.

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Mike 23rd March 2022 - 9:55 am

Did you find any solution to this problem? I have the same issue with EP1 and Literadio 3 ELRS.

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Jerrod 9th November 2021 - 11:41 pm

Thanks for the great info Oscar, maybe a dumb question but

do you know if this will work with Spektrum transmitters? They use the SRXL2 or CRSF/2 protocols.

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Ed 6th November 2021 - 4:01 am

For an ELRS RX to work with a Mamba F411 AIO, would I use the SBus+TX1 to TX+RX in the same way the diagrams show a crossfire tying SBus+TX1 to CH2+CH1? The Mamba docs aren’t particularly clear on whether SBus pin can be used as a generic uart RX1 unless I missed something.

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Manuel Bonow 4th January 2022 - 7:02 pm

If that’s the same Aio that resides in Tina whoop and c25, you can hook up a hm ep Rx the way you explained/ identically to crossfire.
That is for elrs 1.0.2.
For other brand receivers and other firmwares this might not be possible.
Ideal way is a set of full uarts where no inverted pads or sbus are used on)split off.
So you might need to change wiring so you take the UART that is controlling your VTX now.

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Craig 24th October 2021 - 11:42 am

Tapping voltage that way for the fan seems dubious to me without understanding of the circuitry there. Obviously something is being filtered by the capacitors, and adding a fan may disturb the filtering with the voltage spikes/drops it causes. I can’t see the traces, so I couldn’t figure out out the circuitry works, so I opted to simply not use the fan: that’s probably less risky.

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Felipe 17th October 2021 - 10:27 pm

Hello, my EP2 RX blinks the led slowly and doesn’t go into wifi mode. What should I do?

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eric 25th December 2021 - 2:52 am

first, it takes 20 seconds to go into wifi mode so make sure your waiting long enough, if its not going in i would try firmware via uart or betaflight passthrough

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Nabin Bhandari 4th October 2021 - 9:05 am

Hi there,my lua script is showing up instead i am getting “attempt to compare with nil” message.
Anyidea how to solve this?
Thankyou

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Nick Whitehead 2nd October 2021 - 8:41 am

What betaflight build version is ELRS supported from? Ie how old a betaflight build? The reason I ask is that I build my own betaflight versions.

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Marcus Andersson 22nd September 2021 - 8:59 am

Talked to HappyModel today. According to their support there is no need for cooling fan when running at the max output, 250mW, for the ES24TX. There is soon coming another version of the ES24TX that is called ES24TX Pro that has built in fan and capable of 1000mW.

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Matthew 17th September 2021 - 4:38 am

Hey! Where could one find that cover with the mount for the fan? Looks 3D printed. Are there STL files anywhere?

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Xazax 10th September 2021 - 5:45 pm

Will it work with jumper t8sg plus?

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Arras 7th September 2021 - 7:05 pm

Hi,
Thank for the rewiew :)
Can you use ES24TX with FRSky XD9+?
Because no can see the module in the XD9+
Arras

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Oscar 7th September 2021 - 11:32 pm

Yes it should be compatible with Frsky X9D+.

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Denis GALICE 8th September 2021 - 3:59 pm

What would be the procedure please for the XD9 + because I have been trying for weeks but I still do not see the module

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Oscar 12th September 2021 - 5:48 pm

what do you mean you don’t see the module?

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Matt 3rd September 2021 - 2:08 pm

Two important additions that I ran into during setup:

serialrx_inverted and serialrx_halfduplex need to be OFF

If the elrs receiver LED stays on solid after powerup, without ever turning off, it is stuck in the bootloader, caused by the elrs rx pad being pulled low during boot.
Common reason: F4 boards with an inverter for SBUS on one of the serial ports do this, even if you dont use the inverted pad. Use an entirely different serial port for elrs and it will work.

Shoutout to Alessandro for telling me this because I could not find any help in any of the elrs guides or forums.

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Manuel Bonow 29th November 2021 - 2:48 am

Yes I have that exactly same problem on a mamba f411 aio with an jhemcu ep24s receiver.
But it works fine on happymodel ep1.

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DvsDon Fpv 26th February 2022 - 10:54 pm

i have a xilo f4 board how do i know if the pad is inverted or not?

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Fabian 30th March 2022 - 12:54 am

Hi, what do you mean by “serialrx_inverted and serialrx_halfduplex need to be OFF”
Where must I find this option? (yes i’m a noob😅)

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Petar Smiljanic 1st September 2021 - 11:42 am

Is there possibility to use ExpressLRS TX/RX on old PPM radios? Of course with former setting on OpenTX radio/

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Rodrigo C 26th August 2021 - 5:59 am

Hi, thanks for all your work is a great help for everybody.

I’m having trouble with finding sensors with ExpressLRS 2.4? I can only get it to find 10 sensors: (1RSS, 2RSS, RQly, RSNR, ANT, RFMD, TPWR, TRSS, TQly, TSNR) I already tried updating the RX and TX to the latest firmware 1.0.1 with the telemetry option, I also deleted all sensor and discover new sensor, and also increase the Packet Rates but still doesn’t seems to work, any suggestions? could it be that I’m missing to configurate something in betaflight?

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barak 17th November 2021 - 6:25 pm

thank you Oscar for another page packed with info!!
I have the same issue RODRIGO C has, cant get battery voltage (rxbat i believe) on the sensor list.
using DIY 2.4 ghz Tx and happymodel on version 1.2 telemetry enabled. (have the issue with a foxeer F7 on betaflight and F405 wing on arduplane- both latest FW)..
any idea?

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Clay 3rd January 2022 - 6:28 pm

Did you figure this out. I can’t get the battery voltage either

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Peter 14th December 2021 - 6:40 pm

Same issue here. I’ve just installed BetaFPV F4 1S 5A AIO Brushless Flight Controller (onboard ELRS 2.4G). I’m using Taranis x9lite, TX module is BetaFPV nanoTX, latest v1 firmware 1.3.x (FC does not support ELRS 2.0). I can see only 10 sensors you mentioned, nothing more. Had no problems with voltage readings using Frsky R-XSR receiver.

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Gregor 23rd August 2021 - 7:39 am

Is there a foldable antenna for the ES24TX available? It is annoying, for the T-Lite to have this stock-antenna.
Thank you!

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Senthil Kumar 15th August 2021 - 5:44 pm

can Express lrs es24tx lite module in jumper t lite be Connected with frsky r xsr receiver? will it give gud range? How to connect and bind these?

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Oscar 16th August 2021 - 7:25 pm

No. ExpressLRS TX only binds with ExpressLRS RX.

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senthil kumar 3rd September 2021 - 3:20 am

Can we flash frsky r xsr receivers with Express LRS firmware so that it can act as a ExpressLRS RX??

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Chrys Burge 11th August 2021 - 8:33 pm

For the 5V fan connection, could you connect the fan wires to the ground and 5 volt pins in the module bay that power the module?
If so, does voltage become present when external module is selected in the model menu?
If this is the case, it might be easier to connect to these points via the ELRS pin receiving socket as opposed to trying to solder to the point that you did on the board.?

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Blake 13th August 2021 - 1:50 pm

Hi I’m also thinking the same if you hear anything let me know it seems strange they designed the box for a fan but no one knows what to do with it.(Anyway)

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Marcus Andersson 22nd September 2021 - 8:07 am

The external bay has the same voltage as the battery so that wouldn´t be a good idea. Only the internal Multi-Module is powered by 5V.

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Ronald 6th August 2021 - 6:52 pm

EP1 Rx – after initial flash – i get 0:0 Link Quality in my OSD – yet i bind correctly, have 99 RSSI, and can seem to fly (have not tested long range) but at least around a 2 acre yard no range issues. Still shows 0:0 LQ. I can’t figure out why.

I tried to reflash my Rx – but it won’t let me. Every time it WIFI connects, it instantly disconnects me and I can’t get to 10.0.0.1 (however my Tx can get to 10.0.0.1 no problem).

I can’t reflash via UART either — i get this error message all the time like the Rx is not opening its port to accept the reflash? I downloaded the STM files and the VCP files and the Impulse RC Driver fixer. So frustrated!

What the heck? Pretty disappointed. I have good LQ signals and readouts on a different EP1 flashed with the exact same build. I also had good LQ readout on a Happy Model ELRS 5in1 board for the 1s Whoop setup.

Really bummed!!!

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Mike 3rd August 2021 - 8:35 pm

How often do we need to update elrs LUA ? Seems like weekly we get new firmware for the tx and RX.

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Oscar 4th August 2021 - 9:10 pm

Not very often, check firmware release log, it should tell you when LUA script update is necessary. So far (V1.0) I think it’s not necessary yet.

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Kenzo 30th July 2021 - 7:29 pm

Hi bro, btw thank for tutorial, its clear all step by step.
I just try, tx up-to-date rc9, rx up-to-date rc9, bind completely, rssi telemetri good working on radio.
But, in receiver tab, not respond, port uart good, serial crsf.
Can you suggest me, what wrong or what should i do ?
What i miss here xD

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JEFERSON ALESSANDRO DA SILVA 30th July 2021 - 6:34 pm

Attempting to detect FC UART configuration…
** Serial RX config detected: ‘serial 5 64 115200 57600 0 115200’
Enabling serial passthrough…
CMD: ‘serialpassthrough 5 420000’
======== PASSTHROUGH DONE ========
======== RESET TO BOOTLOADER ========
* Using full duplex (CFSF)
Uploading .pio\build\HappyModel_EP_2400_RX_via_BetaflightPassthrough\firmware.bin
esptool.py v3.0
Serial port COM3
Connecting…….._____….._____….._____….._____….._____….._____….._____

A fatal error occurred: Failed to connect to ESP8266: Timed out waiting for packet header
*** [upload] Error 2
========================= [FAILED] Took 20.02 seconds =========================

Environment Status Duration
———————————————– ——– ————
HappyModel_EP_2400_RX_via_BetaflightPassthrough FAILED 00:00:20.024
==================== 1 failed, 0 succeeded in 00:00:20.024 ====================

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Stefano Bellinazzi 24th November 2021 - 3:06 pm

I’ve the same problem.

Have you found a solution?

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R.W. 29th July 2021 - 1:43 am

This particular page is bookmarked and has been referred to many times as I swapped my fleet over. Thanks, this a well-thought out resource!

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Substance242 18th July 2021 - 11:22 am

So far I had “toys” MJX Bugs 6, Fimi A3, and I’m thinking about Eachine Novice 4 RTF, so I started studying lots of new things (betaflight, opentx…), but now the question is – wait a while for some nice RTF package with ExpressLRS…? That is going to happen sooner or later I believe…?

Excellent articles and videos, thank you.

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Phil 18th July 2021 - 12:39 am

Thanks for the great guide! Just followed it to get it working on my QX7 and EP1 RX. Only thing that might need an update is the target that is listed for the RX, it said to use the “HappyModel_EP_2400_RX_via_BetaflightPassthrough” even though you (and I as well) ended up using the WIFI version so it might be good to mention to use the wifi target instead.

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Oscar 18th July 2021 - 9:26 am

It doesn’t seem to matter. You still get the same WiFi capability with the Betaflight Passthrough target.

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Andy 16th July 2021 - 5:39 am

So are EP1 and EP2 equal in Range? If Yes, why should someone choose EP1?
Very curious…

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Oscar 16th July 2021 - 11:41 am

It depends, EP1 allows you to extend the antenna outside of the frame so it doesn’t get obstructed, so in reality it might give you more reliable signal.

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ANDY 16th July 2021 - 1:57 pm

Ok. Thank’s. So for an airplane it might be better to take the EP1…

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Brad Young 6th September 2021 - 8:50 am

I tried to solder the fan you suggested, and yes It was the same happy model board , I was getting 3.3 volts. The capcitor I soldered it to blew AFTER I got it to work. When that little capacitor blew all the lights on my TX board went out , and it no longer works. Awesome.

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Hayward 15th July 2021 - 5:06 pm

As always a great tutorial, would you have one for the ExpressLRS 900Mhz TX and RX

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Oscar 16th July 2021 - 11:38 am

Maybe, but I think ELRS 2.4GHz would be more popular so I did it first.

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Olaf S. 9th July 2021 - 9:36 am

What would have happened if FrSky hat skipped Access and ACCSTv2 and had stayed the opensource route. If they would have been the first who builtin ExpressLRS into their Transmitters than they still would be the leading elephant. Even if they are more expensive – the Gear Akquisition Syndrome of many people would habe bought the First Implementation of new stuff.

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David O Simpson 4th July 2021 - 7:36 am

Thanks for this tutorial.
Helped me get my T-Lite / Tinyhawk communicating. Really appreciate the care to not skip steps and consider us n00bs who might not have done this type of RC link upgrade before.

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Christopher Yotz 27th June 2021 - 11:33 am

Mr. Liang, you are a beautiful human being. Your info above about moving the jumpers on the Happymodel TX in order to flash the TX via UART saved me. This information can’t be found anywhere but here. Thank you so much for your efforts.

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Jan 23rd June 2021 - 11:05 pm

Hi, could you kindly change rx pinouts names?
Its writren vcc and can be confusing for newbies that’s 16.8v, whereas its onły 5v

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Wayne 21st June 2021 - 5:02 am

Updated over UART QX7 won’t connect with the LUA script. I get ???????? 0:0

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Torin Johnson 19th September 2021 - 12:09 pm

I’m also having this issue. Were you able to find a fix?

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Eric Still 1st December 2021 - 10:05 pm

Here are a couple of things I’ve learned fighting with my QX7.
first update the QX7 to latest and greatest OpenTX
create a model with the internal radio off, and the external set to crsf
Unless you’ve done the QX7 crossfire mod (soldering a small board to the motherboard of the QX7) long press the menu button (3 bars on it), “Page” over to hardware, and set the baud rate to 115200.

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Paul 8th January 2022 - 2:38 pm

I had this same issue. I was trying to update a Happymodel TX module that came with ELRS v1.0 to 2.0, so put the v2.0 lua script onto my SD card. This was incorrect, an ELRS module running V1 firmware won’t be usable with the V2 LUA script. I replaced the LUA file with the V1 LUA, and it ran just fine. I was then able to update the TX module to V2, and then replaced the V1 LUA with the latest V2 one.

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Craig 20th June 2021 - 8:38 pm

These are my RSSI settings in Betaflight for ExpressLRS (2.4Ghz EP1 RX) in order to use the full 0 to 100% range of RSSI in my OSD:
set rssi_scale = 255
set rssi_offset = -48
set osd_rssi_alarm = 13
set osd_rssi_dbm_alarm = 99

You can decide whether to use RSSI alarm and/or RSSI Dbm alarm in the OSD tab.

You’ll notice that RSSI drops off very fast in the beginning but slower the lower it gets. Only at about 15 – 20% RSSI will you notice frames being dropped in the LQ but the connection will still be solid. You can go slightly below 10% RSSI without worries as the RSSI is not as erratic there as with most other receivers. Pay more attention to your Dbm and LQ though in the beginning to get a feel as to which RSSI values are safe. LQ does seem to drop off more rapidly the further down it goes. I’d say below 85 is the danger zone.

I would like to set osd_link_quality_alarm but in Betaflight 4.1 the range is 0 – 300, whereas in ExpressLRS LQ varies (and is usually above that range) depending on your frame rate (600 – 700 for 250Hz)

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Oscar 20th June 2021 - 8:57 pm

Thanks for sharing Craig, that’s some useful info!

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grabejud 15th July 2021 - 3:16 pm

btw, how did you get the rssi_offset = -48

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BurningMotorsFPV 19th June 2021 - 4:04 pm

Hi,

awesome writeup!
One mistake though: Under the section where you describe how to flash the TX via uart. There is no boot button on the tx that you have to press. Just move the jumpers and install the cp210x drivers and hit “build & flash”.

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Gary Cross 19th June 2021 - 3:16 pm

Excellent article, will help a lot of people including me. Very informative and well put together. Thank you.

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RaKr 18th June 2021 - 1:53 pm

Great Work – thank you!

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MJDOZ 19th June 2021 - 10:56 am

OPENTX 2.3.12 has a bug that it does not fully support 500hz as of 19 June 2021 and falls back to 250hz Sampling rate

If you are somebody who must have 500hz then use the 2.3.10 ERLS version of OpenTX or the latest RC of EDGETX

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Prudi 18th June 2021 - 6:35 am

Need tutorial how to flash TX via USB, since my module stuck with syntax error mesage and can’t access tx menu (always return to ELRS tools menu) . It happened when I change telemetry ratio to 1:4.

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Prudi 20th June 2021 - 9:58 am

Thanks for USB update firmware tutorial, my module is coming back online

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Danny 17th June 2021 - 8:49 pm

Great guide and easy to understand explanation, the best so far, thanks Oscar ! On Opentx 2.3.12 stock firmware seems You’ve been limited in choice to 25Hz. That’s what I’ve read on FB.

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MJDOZ 17th June 2021 - 10:10 pm

OpenTX 2.3.12 supports all speeds except 25hz

If you want to use 25hz you will need EDGETX currently on GitHub as version 2.4 RC1 as 16 June 2021

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Keczejo 17th June 2021 - 2:00 pm

Lite module is only for Jumper t lite. To use it in x-lite or tango 2 you have to print adapter and solder special connector.

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Oscar 17th June 2021 - 2:18 pm

Thank you I just updated the post.

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Rishi Thakur 19th June 2021 - 8:59 am

Open tx 2.3.12 has an issue and currently can’t run 500Hz

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Luis Leston 17th June 2021 - 1:57 pm

Amazing documentation. I am really impressed with the quality of your work.

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Martin 17th June 2021 - 2:16 pm

Oscar is doing great job and helping lots of people in the hobby. Consider to support him on patreon. Thx!

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Jonas Liang 17th June 2021 - 1:33 pm

Nice guide! Opentx 2.3.12 stock firmware is released.may be no need to flash nightly build

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Oscar 17th June 2021 - 2:23 pm

Hahaha.. I knew I would have to update the post the moment I publish it!
I will check it out tonight, thank you.

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Thomas Shue 7th September 2021 - 5:24 am

Where can i buy an adapter to go from the MINI to JR bay?

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Oscar 7th September 2021 - 11:29 pm

I got mine from here: https://oscarliang.com/product-v6qi
But it’s only the pins and PCB, you need to get the case 3D printed.

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