FCC ID: 2BBP3-ER4 receiver

ER4 Thank you for purchasing the Radiomaster ER4 ExpressLRS receiver. The ER4 receiver is based on the revolutionary ExpressLRS system. It oers high performance, high reliability, exible conguration, fast response speed and ultra-long range bringing you brand new experience with your hobby. Important:

1.The recommended ELRS LUA settings on the remote-control end are:

- Standard servos:

Packet Rate 100Hz Full Telem Ratio Std (1:32)default if unsure Switch Mode 8ch

- Performance servos:

Packet Rate 333Hz Full Telem Ratio Std (1:128) Switch Mode 8ch 2: The maximum input voltage for the EXT-V (external voltage input) telemetry reading is 35V. Do not exceed 35V or the receiver will be damaged. 3: The EXT-V (external voltage input) of the ER4 is accessed via the EXT-V solder pad on the PCB. A single wire must be soldered to this pad and connected to the positive wire of the battery or ESC. If no EXT-V power source is found, the ER4 will default to reading the voltage on the receiver pins, only one voltage input can be used at the any given time. 4: If the power supplied is 7.4V or higher, please ensure that the receiver is in an open and ventilated area of the model for better heat dissipation. 5: Calibration of the telemetry voltage will be required on your radio. Navigate to the telemetry page on your radio and locate the RxBt sensor. Edit the sensor settings and adjust the oset until the displayed reading matches the actual voltage of the battery in the model. If there is a large dierence, adjustment of the ratio may also be required.

*For best results, calibrate the voltage of your radio using a fully charged battery of the correct cell count intended for use in the model. 6: ExpressLRS Arming requirements and the use of Channel 5. The ER4 receiver has 4 channels and does not require any channel outputs to be re-mapped however it is still recommended to assign CH5 on your radio to a switch such as your throttle cut switch so the RF module in your radio can be armed and disarmed which will provide benets such as dynamic power. Please visit https://www.expresslrs.org/ to learn more on the importance of setting up arming. The Radiomaster ER4 receiver can drive 4 servos simultaneously. Designed with a very small volume, it is suitable for small aircraft models, ship models, car models and other models that require a small or lightweight receiver while still providing full range. Product Features:

Power supply: DC 4.5 - 8.4V Antenna type: 15cm high sensitivity antenna Wireless protocol: ExpressLRS 3.3.0 pre-installed Output channel: 4CH PWM Telemetry power: 100mw Battery voltage detection range: DC 4.0 - 35V Weight: 3.0 grams Dimensions: 30*15*5mm Firmware:

Device Category: Radiomaster 2.4Ghz Device: RadioMaster ER4 2400 PWM RX CH1 CH2 CH3 CH4 BOOT Binding method (Traditional):

1. The rst time you power on your receiver, the LED will double blink. This indicates that the receiver is in bind mode. If this is not the case, hold down the boot button for 10 seconds to reset the receiver. 2. Open the ExpressLRS LUA on your remote controller and select [BIND], then conrm. 3. A successful bind is indicated by the light being a steady on, indicating that frequency binding was successful. Binding method (Passphrase). 1. Open the ExpressLRS LUA and navigate to the Wi Connectivity page. Select the Enable Wi option and connect to your radios wi with a mobile phone, tablet or PC (See TX Wi notes below). Open the WebUI (Express LRS web page on http://10.0.0.1/) and choose a unique bind phrase. Note Bind phrases are not secret and can be read. Save and Reboot. 2. Power up the receiver and wait 60 seconds for the LED to blink rapidly to indicate Wi mode. Connect your phone, tablet or PC to the receivers Wi (See TX Wi notes below). Open the WebUI (Express LRS web page on http://10.0.0.1/) and enter the matching bind phrase previously entered on your radio. Note Bind phrases are not secret and can be read. Save and Reboot. Once a radio and a receiver have the same bind phrase set they will automatically bind. Note: To bind the receiver a second time or to another radio, power cycle the receiver 3 times. On the third power cycle, the LED will double blink indicating bind mode. If you cannot successfully enter bind mode with the 3 power cycle method, you can hold down the boot button for 10 seconds to reset the receiver to bind mode or use the passphrase method below. WARNING: All previous settings in the receiver will be erased and need to be set again when using the reset button. TX Wi notes WiFi default network name: ExpressLRS TX WiFi default password: expresslrs Default URL: http://10.0.0.1/ (Open in browser) RX Wi notes:

WiFi default network name: ExpressLRS RX WiFi default password: expresslrs Default URL: http://10.0.0.1/ (Open in browser) FCC Warning This device complies with part 15 of the FCC Rules. Operation is subject to the following two conditions:

(1) This device may not cause harmful interference, and (2) this device must accept any interference received, including interference that may cause undesired operation. Any Changes or modications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. Note: 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 to provide reasonable protection against harmful interference 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 o and on, the user is encouraged to try to correct the interference 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 dierent from that to which the receiver is connected.

-Consult the dealer or an experienced radio/TV technician for help. This equipment complies with FCC radiation exposure limits set forth for an uncontrolled environment. This equipment should be installed and operated with minimum distance 20cm between the radiator & your body. European agent information:

eVatmaster Consulting GmbH AddBettinastr. 30,60325 Frankfurt am Main,Germany

- Shenzhen Radiomaster Co.,Ltd -

Federal Communications Commission Authorization and Evaluation Division Equipment Authorization Branch 7435 Oakland Mills Road Columbia, MD 21046 U.S. Agent Designation 7/27/23

[Shenzhen Radiomaster Co.,Ltd] acknowledges their consent for the following contact located in the United States to act as their agent for service of process for the equipment for which authorization is sought (FCC ID: [2BBP3-ER4 ]):

Name and company of U.S. agent:SUN BEYOND CONSULTING LTD Physical U.S. address of agent:OFFICE NO.448,4TH FLOOR,90 CANAL STREET BOSTON,, MA 2114 FRN of U.S. agent:0033598426 Email address of U.S. agent:582643537@qq.com

[SUN BEYOND CONSULTING LTD] acknowledges their obligation to accept service of process on behalf of [Shenzhen Radiomaster Co.,Ltd].

[Shenzhen Radiomaster Co.,Ltd] with the FRN [0033900978] accepts its obligation to maintain an agent for service of process in the United States for no less than one year after either the grantee has permanently terminated all marketing and importation of the applicable equipment within the U.S., or the conclusion of any Commission-related administrative or judicial proceeding involving the equipment, whichever is later. By signing this form, we confirm the above and that we are aware of the application requirements listed under 2.911(d)(7). Sincerely, Signature

[Name]owen lee

[Title]manager 4 0 V

[Company] Shenzhen Radiomaster Co.,Ltd

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_ 8 4 The information provided in this letter is based on the referenced rule parts of Title 47 of the CFR as well as KDB 986446 D01. An expiration date for this letter does not exist. In case the U.S. agent changes, the grantee is obligated to notify the FCC within 30 days via the granting TCB.

- Shenzhen Radiomaster Co.,Ltd -

[Name of U.S. agent]Peter Zhang

[Title of U.S. agent]manager

[Company of U.S. agent]SUN BEYOND CONSULTING LTD The information provided in this letter is based on the referenced rule parts of Title 47 of the CFR as well as KDB 986446 D01. An expiration date for this letter does not exist. In case the U.S. agent changes, the grantee is obligated to notify the FCC within 30 days via the granting TCB.

- Shenzhen Radiomaster Co.,Ltd -

Federal Communications Commission Authorization and Evaluation Division Equipment Authorization Branch 7435 Oakland Mills Road Columbia, MD 21046 7/27/23 To whom it may concern:

We, [Shenzhen Radiomaster Co.,Ltd], hereby certify that the equipment for which authorization is sought (FCC ID: [2BBP3-ER4]) is not covered equipment prohibited from receiving an equipment authorization pursuant to 2.903 of the FCC rules. We also certify that, as of the date of the filing of the application, we are not identified on the Covered List (https://www.fcc.gov/supplychain/coveredlist) as an entity producing covered equipment. By signing this form, we confirm the above and that we are aware of the application requirements listed under 2.911(b) and (d)(5) and (6). Sincerely, Signature

[Name]owen lee

[Title]manager

[Company] Shenzhen Radiomaster Co.,Ltd The information provided in this letter is based on the referenced rule parts of Title 47 of the CFR as well as KDB 986446 D01. 2 0 V

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