BETAFPV ELRS Nano RF TX Module High Refresh Rate Long Range Performance Ultra Low Latency User Manual
- June 6, 2024
- BetaFPV
Table of Contents
BETAFPV ELRS Nano RF TX Module High Refresh Rate Long Range
Performance Ultra Low Latency
BETAFPV Nano RF TX module is based on ExpressLRS project, open source RC link
for RC applications. ExpressLRS aims to achieve the best possible link
preformance in both speed, latency and range. This makes ExpressLRS one of the
fastest RC links available while still offering long-range preformance.
Github Project Link: https://github.com/ExpressLRS
Facebook Grau p: https://fwww.facebook.com/groups/636441730280366
Specifications
-
Packet refresh rate:
25Hz/50Hz/100Hz/200Hz (915MHz/868M Hz)
50Hz/150Hz/250Hz/500Hz (2.4GHz) -
RF output power:
25mW/50mW/100mW/250mW/500mW (2.4GHz)
100mW/250mW/500mW (915M Hz/868MHz) -
Frequency bands (Nano RF Module 2.4G version): 2.4GHz ISM
-
Frequency bands (Nano RF Module 915MHz/868MHz version): 915MHz FCC/868MHz EU
-
Input voltage: DC 5V~l2V
-
USB port: Type-C
BETAFPV Nano RF module is compatible with radio transmitter which has the nano module bay (AKA lite module bay, e.g. Frsky Taranis X-Lite, Frsky Taran is X9D Lite, TBS Tango 2).
Basic Configuration
ExpressLRS uses the Crossfire serial protocol (AKA CRSF protocol) to
communicate between the radio transmitter and the Nano RF module. So make sure
your radio transmitter support the CRSF serial protocol. Next, we use the
radio transmitter with Open TX system to show how to setup the CRSF protocol
and LUA script. 
Note: Please assemble the
antenna before power on. Otherwise, the PA chip in the Nano TX module will be
damaged permanently.
CRSF Protocol
ExpressLRS uses the CRSF serial protocol to communicate between the radio
transmitter and the RF TX module. To set this up, in OpenTX system, enter into
model settings, and on the “MODEL SETUP” tab, turn off the “Internal RF”. Next
enable “External RF” and select “CRSF” as the protocol. 
LUA Script
ExpressLRS use the Open TX LUA script to control the TX module, like bind or setup.
- Save the ELRS.lua script files onto the radio transmitter’s SD Card in the Scripts/Tools folder;
- Long press the “SYS” button (for RadioMaster Tl6 or similar radios) or the “Menu” button (for Frsky Taran is X9D or similar radios) to access the Tools Menu where you can find ELRS script ready to run with only one click;
- Below image show the LUA script run successfully;
With the LUA script, pilot could check and setup some configurations of the Nano RF TX module.
0:250| On the top right. Indicator which tells how many bad UART packets and
how many packets it’s getting from the radio per second. It can be used to
confirm the communication between the radio tansmitter and the RF TX module is
working properly. e.g. 0:200 means 0 bad packets and 200 good packets per
second.
---|---
Rkt. Rate| RF transmitter packet rate.
TLM Ratio| Receiver telemetry ratio.
Power| RF TX module output power.
RF Freq| Frequency bands.
Bind| Set the RF TX module into binding status.
Wifi Update| Open the WIFI function for firmware update.
Note: The newest ELRS.lua script file is available in BETAFPV Support website (Link in More Information Chapter).
Bind
The Nano RFTX module comes with offically major release Vl.0.0 protocol and no
Binding Phrase inlcuded. So please make sure the receiver works on offically
major release Vl.0.0~Vl.1.0 protocol. And no Binding Phrase setted.
Nano RF TX module could enter binding status via ELRS.lua script, as
description in “LUA Script” chapter.
Besides, short press the button three times on the module could also enter
binding status. 
Note: The LED will NOT flash when enter binding status. The module will
exit from binding status 5 seconds later auto.
Note: If you reflash firmware of the RF TX module with your own Binding
Phrase, please make sure the receiver has the same Binding Phrase. The RFTX
module and the receiver will bind automatically in this situation.
Output Power Switch
Nano RF TX module could switch the output power via ELRS.lua script, as
description in “LUA Script” chapter.
Besides, long press the button on the module could switch the output power.
The RF TX module output power and LED indication as
show below.
| LED Color | RF output power |
|---|---|
| Blue | l 00m W |
| Purpl e | 250mW |
| Red | S00mW |
More Information
As ExpressLRS project is still in frequently update, please check BETAFPV
Support (Technical Support -> ExpressLRS Radio Link) for more details and
newest maunal.
https://support.betafpv.com/hc/en-us
- Newest user manual;
- How to upgrade the firmware;
- FAQ and troubleshooting.
FCC statement
This equipment has been tested and found to comply with the limits for a Class
B digital device, pursuant to part 15 of the FCC Rules. These limits are
designed lo provide reasonable protection against harmful interterence in a
residential installation. This equipment generates, uses and
can radiate radio frequency energy and, if not installed and used in
accordance with the
instructions, may cause harmful interference to radio communications. However,
there is no
guarantee that interference will not occur in a particular installation. If
this equipment does
cause harmful interference to radio or television reception, which can be
determined by turning
the equipment off and on, the user is encouraged to try to correct the
interterence by one or
more of the following measures
- Reorient or relocate the receiving antenna
- Increase the separation between the equipment and receiver
- Connect the equipment into an outlet on a circuit different from that to which the receiver is connected
- Consult the dealer or an expelienced radio/TV technician for help
Caution: Any changes or modifications to this device not explicitly
approved by manufacturer could void your autholity to operate this equipment
This device complies with part 15 of the FCC Rules.
Operation is subtect to the following two conditions:
- This device may not cause harmful interference, and
- this device must accept any interference received, including interference that may cause undesired operation
RF Exposure Information
The device has been evaluated to meet general RF exposure requirement. The
device can be used in portable exposure condition without restliction