Radio Test Report

1.1 Client Information

1.2 General Description of EUT (Equipment Under Test)

• EUT Name: Wireless Doorbell Transmitter
• Models No.: F55, M520+F55, M520+F55X2, M520X2+F55, M520X2+F55X2, M520X3+F55X2, M508+F55, M508+F55X2, M508X2+F55, M508X2+F55X2, M508X3+F55X2, M523+F55, M523+F55X2, M523X2+F55, M523X2+F55X2, M523X3+F55X2
• Model Different: All PCB boards and circuit diagrams are the same, the only difference is that appearance color.
• Operation Frequency: 433.92 MHz
• Max Out Power: 67.11 dBuV/m (PK Max.), 58.61 dBuV/m (AV Max.)
• Antenna Gain: -6.3dBi PCB Antenna
• Modulation Type: OOK
• Power Rating: DC 3.0V by button cell
• Hardware Version: KR-F55-CE-V1.1-2434

1.3 Block Diagram Showing the Configuration of System Tested

A simple block diagram shows the EUT in TX Mode.

1.4 Description of Support Units

The EUT was tested as an independent unit.

1.5 Description of Test Mode

To investigate the maximum EMI emission characteristics generated from EUT, the test system was pre-scanning tested based on the consideration of following EUT operation mode or test configuration mode which possibly have effect on EMI emission level. Each of these EUT operation mode(s) or test configuration mode(s) mentioned below was evaluated respectively.

Note: (1) During the testing procedure, the continuously transmitting mode was programmed by the customer. (2) The EUT is considered a fixed unit, and it was pre-tested on the positioned of each 3 axis: X axis, Y axis and Z axis. The worst case was found positioned on Z-plane. Therefore, only the test data of this Z-plane were used for radiated emission measurement test.

1.6 Description of Test Software Setting

During testing, channel & Power controlling software provided by the customer was used to control the operating channel as well as the output power level. The RF output power selection is for the setting of RF output power expected by the customer and is going to be fixed on the firmware of the final end product power parameters of transmitting mode.

• RF Power Setting in Test SW: DEF

1.7 Measurement Uncertainty

The reported uncertainty of measurement y±U, where expended uncertainty U is based on a standard uncertainty multiplied by a coverage factor of k=2, providing a level of confidence of approximately 95 %.

1.8 Test Facility

The testing report was performed by Shenzhen Toby Technology Co., Ltd., in their facilities located at 1/F., Building 6, Rundongsheng Industrial Zone, Longzhu, Xixiang, Bao'an District, Shenzhen, Guangdong, China. At the time of testing, the following bodies accredited the Laboratory:

• CNAS (L5813): The Laboratory has been accredited by CNAS to ISO/IEC 17025: 2017 General Requirements for the Competence of Testing and Calibration Laboratories for the competence in the field of testing. And the Registration No.: CNAS L5813.
• A2LA Certificate No.: 4750.01: The laboratory has been accredited by American Association for Laboratory Accreditation(A2LA) to ISO/IEC 17025:2017 General Requirements for the Competence of Testing and Calibration Laboratories for the technical competence in the field of Electrical Testing. And the A2LA Certificate No.: 4750.01. FCC Accredited Test Site Number: 854351. Designation Number: CN1223.
• IC Registration No.: (11950A): The Laboratory has been registered by Certification and Engineering Bureau of Industry Canada for radio equipment testing. The site registration: Site# 11950A. CAB identifier: CN0056.

5.1 Test Standard and Limit

5.1.1 Test Standard

FCC Part 15.207

5.1.2 Test Limit

Notes:

1. *Decreasing linearly with logarithm of the frequency.
2. The lower limit shall apply at the transition frequencies.
3. The limit decrease in line with the logarithm of the frequency in the range of 0.15 to 0.50MHz.

5.2 Test Setup

A diagram illustrates the conducted emission test setup, showing the EUT connected via a LISN to a Receiver. The EUT is positioned 0.8m from the ground plane, with the LISN 0.8m from the EUT. A 0.4m distance is shown between EUT and LISN. The receiver is connected to the LISN.

5.3 Test Procedure

• The EUT was placed 0.8 meters from the horizontal ground plane with EUT being connected to the power mains through a line impedance stabilization network (LISN). All other support equipments powered from additional LISN(s). The LISN provide 50 Ohm/ 50uH of coupling impedance for the measuring instrument.
• Interconnecting cables that hang closer than 40 cm to the ground plane shall be folded back and forth in the center forming a bundle 30 to 40 cm long.
• I/O cables that are not connected to a peripheral shall be bundled in the center. The end of the cable may be terminated, if required, using the correct terminating impedance. The overall length shall not exceed 1 m.
• LISN at least 80 cm from nearest part of EUT chassis.

The bandwidth of EMI test receiver is set at 9 kHz, and the test frequency band is from 0.15MHz to 30MHz.

5.4 Deviation From Test Standard

No deviation

5.5 EUT Operating Mode

Please refer to the description of test mode.

5.6 Test Data

The EUT is powered by DC battery, no requirement for this test item.

6.1 Test Standard and Limit

6.1.1 Test Standard

FCC 15.231e

6.1.2 Test Limit

According to FCC 15.231(e) requirement: In addition to the provisions of Section 15.205, the field strength of emissions from intentional radiators operated under this Section shall not exceed the following:

** Linear interpolations, the formulas for calculating the maximum permitted fundamental field strengths are as follows:

1. for the band 130~174 MHz, uV/m at 3 meters= 22.7273(F)-2454.5455;
2. for the band 260~470 MHz, uV/m at 3 meter= 16.6667(F)-2833.3333.
3. The maximum permitted unwanted emissions level is 20 dB below the maximum permitted fundamental level. In addition field strength of any emissions which appear inside of the restriction band shall not exceed the general radiated emissions limits in FCC Part15.209.

Note:

1. The tighter limit applies at the band edges.
2. For above 30MHz: Emission Level(dBuV/m)=20log Emission Level(uV/m)
3. For 0.009~0.490MHz: Emission Level(dBuV/m)=20log Emission Level(uV/m) +40log(300/3)
4. For 0.049~30MHz: Emission Level(dBuV/m)=20log Emission Level(uV/m) +40log(30/3)

So the field strength of emission limits have been calculated in below table.

6.2 Test Setup

Diagrams show radiated measurement setups for frequencies below 30MHz, below 1000MHz, and above 1GHz. These setups typically involve the EUT, an antenna (RX Antenna), a spectrum analyzer/receiver, and an amplifier, arranged at specified distances (e.g., 3m). The setups include a metal full soldered ground plane.

6.3 Test Procedure

• Radiated measurement
• The measuring distance of 3m shall be used for measurements at frequency up to 1GHz and above 1 GHz. The EUT was placed on a rotating 0.8m high above ground, the table was rotated 360 degrees to determine the position of the highest radiation.
• Measurements at frequency above 1GHz. The EUT was placed on a rotating 1.5m high above the ground. RF absorbers covered the ground plane with a minimum area of 3.0m by 3.0m between the EUT and measurement receiver antenna. The RF absorber shall not exceed 30cm in high above the conducting floor. The table was rotated 360 degrees to determine the position of the highest radiation.
• The Test antenna shall vary between 1m and 4m, Both Horizontal and Vertical antenna are set to make measurement.
• The initial step in collecting conducted emission data is a spectrum analyzer peak detector mode pre-scanning the measurement frequency range. Significant peaks are then marked and then Quasi Peak detector mode re-measured.
• If the Peak Mode measured value compliance with and lower than Quasi Peak Mode Limit Below 1 GHz, the EUT shall be deemed to meet QP Limits and then no additional QP Mode measurement performed. But the Peak Value and average value both need to comply with applicable limit above 1 GHz.
• Testing frequency range 30MHz-1GHz the measuring instrument use VBW=120 kHz with Quasi-peak detection. Testing frequency range 9KHz-150Hz the measuring instrument use VBW=200Hz with Quasi-peak detection. Testing frequency range 9KHz-30MHz the measuring instrument use VBW=9kHz with Quasi-peak detection.
• Testing frequency range above 1GHz the measuring instrument use RBW=1 MHz and VBW=3 MHz with Peak Detector for Peak Values, and use RBW=1 MHz and VBW=10 Hz with Peak Detector for Average Values.
• For the actual test configuration, please see the test setup photo.

6.4 Deviation From Test Standard

No deviation

6.5 EUT Operating Mode

Please refer to the description of test mode.

6.6 Test Data

Radiated measurement please refer to the Attachment A inside test report.

7.1 Test Standard and Limit

7.1.1 Test Standard

FCC 15.231

7.1.2 Test Limit

The 99%bandwidth of the emissions shall be no wider than 0.25% of the center frequency for devices operating above 70 MHz and below 900 MHz. So the emission bandwidth limits have been calculated in below table.

7.2 Test Setup

A diagram shows the EUT connected to a Spectrum Analyzer for conducted bandwidth measurement.

7.3 Test Procedure

1. Set Spectrum Analyzer Center Frequency= Fundamental Frequency, RBW=10 kHz, VBW= 30 kHz, Span= 1 MHz.
2. Measured the spectrum width with power higher than 20 dB below carrier.

7.4 Deviation From Test Standard

No deviation

7.5 EUT Operating Mode

Please refer to the description of test mode.

7.6 Test Data

Please refer to the Attachment B.

8.1 Test Standard and Limit

8.1.1 Test Standard

FCC 15.231

8.1.2 Test Limit

According to FCC 15.231a, A manually operated transmitter shall employ a switch that will automatically deactivate the transmitter within not more than 5 seconds of being released.

8.2 Test Setup

A diagram shows the EUT connected to a Spectrum Analyzer for release time measurement.

8.3 Test Procedure

1. Setup the EUT as show in the block diagram above.
2. Set Spectrum Analyzer Centre Frequency= Fundamental Frequency, RBW=100 kHz, VBW= 300 kHz, Span= 0 Hz. Sweep Time= 5 Seconds.
3. Setup the EUT as normal operation and press Transmitter button.
4. Set Spectrum Analyzer View, Delta Mark time.

8.4 Deviation From Test Standard

No deviation

8.5 EUT Operating Mode

Please refer to the description of test mode.

8.6 Test Data

Please refer to the Appendix C.

9.1 Test Standard and Limit

9.1.1 Test Standard

FCC 15.231

9.2 Test Setup

A diagram shows the EUT connected to a Spectrum Analyzer for duty cycle measurement.

9.3 Test Procedure

1. The EUT was placed on a turntable which is 0.8m above ground plane.
2. Set EUT operating in continuous transmitting mode.
3. Set the Spectrum Analyzer to the transmitter carrier frequency, and set the spectrum analyzer resolution bandwidth (RBW) to 100 kHz and video bandwidth (VBW) to 300 kHz, Span was set to 0 Hz.
4. The Duty Cycle was measured and recorded.

9.4 Deviation From Test Standard

No deviation

9.5 EUT Operating Mode

Please refer to the description of test mode.

9.6 Test Data

Please refer to the Appendix D.

11.1 Test Standard and Limit

11.1.1 Test Standard

FCC Part 15.203

11.1.2 Requirement

An intentional radiator shall be designed to ensure that no antenna other than that furnished by the responsible party shall be used with the device. The use of a permanently attached antenna or of an antenna that uses a unique coupling to the intentional radiator shall be considered sufficient to comply with the provisions of this Section. The manufacturer may design the unit so that a broken antenna can be replaced by the user, but the use of a standard antenna jack or electrical connector is prohibited.

11.2 Deviation From Test Standard

No deviation

11.3 Antenna Connected Construction

The gains of the antenna used for transmitting is -6.3dBi, and the antenna de-signed with permanent attachment and no consideration of replacement. Please see the EUT photo for details.

11.4 Test Data

The EUT antenna is a PCB Antenna. It complies with the standard requirement.