FCC Radio Test Report

Prepared For

Company: Shenzhen Sowak Electronic Co., Ltd

Address: No.88, Jinkang Road, Jinsha Community, Kengzi Street, Pingshan, Shenzhen, China

Prepared By

Company: Shenzhen United Testing Technology Co., Ltd.

Address: 2F, Annex Bldg, Jiahuangyuan Tech Park, #365 Baotian 1 Rd, Tiegang Community, Xixiang Str, Bao'an District, Shenzhen, China

http://www.uni-lab.hk

Test Result Certification

Applicant: Shenzhen Sowak Electronic Co., Ltd

Manufacturer: Shenzhen Sowak Electronic Co., Ltd

Product Description: True Wireless Earphones

Test Methods: FCC Rules and Regulations Part 15 Subpart C Section 15.249, ANSI C63.10: 2013

Date of Test: Mar. 31, 2022 ~ Apr. 14, 2022

Date of Issue: Apr. 15, 2022

Test Result: Pass

Prepared by: Jackson Fang (Editor)

Reviewer: Kahn yang (Supervisor)

Approved & Authorized Signer: Liuze (Manager)

1 Test Summary

1.1 Test Procedures and Results

1.2 Test Facility

Test Firm: Shenzhen United Testing Technology Co., Ltd.

Address: 2F, Annex Bldg, Jiahuangyuan Tech Park, #365 Baotian 1 Rd, Tiegang Community, Xixiang Str, Bao'an District, Shenzhen, China

The testing quality ability of our laboratory meets with "Quality Law of People's Republic of China" Clause 19. The testing quality system of our laboratory meets with ISO/IEC-17025 requirements. This approval result is accepted by MRA of APLAC.

Our test facility is recognized, certified, or accredited by the following organizations:

• A2LA Certificate Number: 4747.01. The EMC Laboratory has been accredited by A2LA, and in compliance with ISO/IEC 17025:2017 General Requirements for testing Laboratories.
• FCC Registration Number: 674885. The EMC Laboratory has been registered and fully described in a report filed with the (FCC) Federal Communications commission.
• IC Registration Number: 21947. The EMC Laboratory has been registered and fully described in a report filed with the (IC) Industry Canada.

1.3 Measurement Uncertainty

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

A. Conducted Measurement:

B. Radiated Measurement:

2 General Information

2.1 General Description of EUT

2.2 Carrier Frequency of Channels

Channel List:

2.3 Test Mode

The EUT was programmed to be in continuously transmitting mode.

2.4 Test Setup

Operation of EUT during Conducted and Below 1GHz Radiation testing:

Diagram Description: The EUT is placed on a table, connected to an AC Power source via an Adapter. A Test Receiver is also present in the setup.

Operation of EUT during Above 1GHz Radiation testing:

Diagram Description: The EUT is shown as the primary component in the test setup.

2.5 Description Test Peripheral and EUT Peripheral

The EUT has been tested as an independent unit together with other necessary accessories or support units. The following support units or accessories were used to form a representative test configuration during the tests.

Note: 1. The support equipment was authorized by Declaration of Confirmation. 2. For detachable type I/O cable should be specified the length in cm in『Length』column. 3. "YES" is means "shielded" "with core"; "NO" is means "unshielded" "without core".

2.6 Measurement Instruments List

Conduction Emissions Measurement

Radiated Emissions Measurement

3 Conducted Emission

3.1 Test Limit

For unintentional device, according to § 15.207(a) Line Conducted Emission Limits is as following:

* Decreasing linearly with the logarithm of the frequency.

For intentional device, according to §15.207(a) Line Conducted Emission Limit is same as above table.

3.2 Test Setup

Diagram Description: The test setup includes a Vertical Reference Ground Plane, the EUT, and a Test Receiver. The EUT is positioned at a height of 0.8m above the Ground Plane. A Horizontal Reference Ground Plane is also shown. Support units are connected to a second LISN, and both LISNs (AMN) are 80 cm from the EUT and at least 80 cm from other units and metal planes.

3.3 Test Procedure

1. The equipment was set up as per the test configuration to simulate typical actual usage per the user's manual. The EUT is placed on a wooden table with a height of 0.8 meters and is placed on the ground plane as per ANSI C63.10.
2. Support equipment, if needed, was placed as per ANSI C63.10.
3. All I/O cables were positioned to simulate typical actual usage as per ANSI C63.10.
4. If a EUT received DC power from the USB Port of Notebook PC, the PC's adapter received AC120V/60Hz power through a Line Impedance Stabilization Network (LISN) which supplied power source and was grounded to the ground plane.
5. All support equipments received AC power from a second LISN, if any.
6. The EUT test program was started. Emissions were measured on each current carrying line of the EUT using a spectrum Analyzer / Receiver connected to the LISN powering the EUT. The LISN has two monitoring points: Line 1 (Hot Side) and Line 2 (Neutral Side). Two scans were taken: one with Line 1 connected to Analyzer / Receiver and Line 2 connected to a 50 ohm load; the second scan had Line 1 connected to a 50 ohm load and Line 2 connected to the Analyzer / Receiver.
7. Analyzer / Receiver scanned from 150 kHz to 30MHz for emissions in each of the test modes.

3.4 Test Result

PASS

Remark: 1. All modes were tested at AC 120V and 240V, only the worst result of AC 120V was reported. 2. All modes were test at Low, Middle, and High channel, only the worst result of GFSK Low Channel was reported.

Test Data (AC 120V, 60Hz, Phase: Line)

Graph Description: A plot showing RF Line Voltage (dBuV) versus Frequency (MHz) for Conducted Emission testing. Two curves are displayed, labeled QP (Quasi-Peak) and AVG (Average), showing emission levels below the defined limits.

Remark: Factor = Insertion Loss + Cable Loss, Result = Reading + Factor, Margin = Result – Limit.

Test Data (AC 120V, 60Hz, Phase: Neutral)

Graph Description: A plot showing RF Line Voltage (dBuV) versus Frequency (MHz) for Conducted Emission testing. Two curves are displayed, labeled QP (Quasi-Peak) and AVG (Average), showing emission levels below the defined limits.

Remark: Factor = Insertion Loss + Cable Loss, Result = Reading + Factor, Margin = Result – Limit.

4 Radiated Emission

4.1 Test Limit

For unintentional device, according to § 15.209(a), except for Class B digital devices, the field strength of radiated emissions from unintentional radiators at a distance of 3 meters shall not exceed the following values:

For intentional device, according to § 15.209(a), the general requirement of field strength of radiated emissions from intentional radiators at a distance of 3 meters shall not exceed the above table.

Limit: (Field strength of the fundamental signal)

4.2 Test Setup

Diagram Description (Below 30MHz): The EUT is placed on a turntable (0.8m height) above a Ground Plane. A 3m distance separates the EUT from the RX Antenna (1m height).

Diagram Description (30MHz~1GHz): The EUT is placed on a turntable (0.8m height) above a Ground Plane. A 3m distance separates the EUT from the antenna feed point. The antenna height is adjustable from 1-4m. A Receiver and Amplifier are present.

Diagram Description (Above 1GHz): The EUT is placed on a turntable (1.5m height) above a Ground Plane. A 3m distance separates the EUT from the antenna feed point. The antenna height is adjustable from 1-4m. A Receiver and Amplifier are present.

4.3 Test Procedure

1. Below 1GHz measurement the EUT is placed on turntable which is 0.8m above ground plane. And above 1GHz measurement EUT was placed on low permittivity and low tangent turn table which is 1.5m above ground plane.
2. The turntable shall be rotated for 360 degrees to determine the position of maximum emission level.
3. EUT is set 3m away from the receiving antenna, which is varied from 1m to 4m to find out the highest emissions.
4. Maximum procedure was performed on the six highest emissions to ensure EUT compliance.
5. And also, each emission was to be maximized by changing the polarization of receiving antenna both horizontal and vertical.
6. Repeat above procedures until the measurements for all frequencies are complete.
7. The test frequency range from 9kHz to 25GHz per FCC PART 15.33(a).

Note: For battery operated equipment, the equipment tests shall be performed using a new battery.

4.4 Test Result

PASS

Remark: 1. All modes were test at Low, Middle, and High channel, only the worst result of GFSK Low Channel was reported for below 1GHz test. 2. By preliminary testing and verifying three axis (X, Y and Z) position of EUT transmitted status, it was found that "X axis" position was the worst, and test data recorded in this report. 3. Radiated emission test from 9kHz to 10th harmonic of fundamental was verified, and no emission found except system noise floor in 9kHz to 30MHz and not recorded in this report.

Test Data (Below 1GHz)

Graph Description: A plot showing RF Emission Level (dBuV/m) versus Frequency (MHz) for Radiated Emission testing below 1GHz. Two lines represent Limit and Margin, showing measured emissions below the limit.

Remark: Absolute Level = Reading Level + Factor, Margin = Absolute Level – Limit

Test Data (Below 1GHz, Vertical Polarization)

Graph Description: A plot showing RF Emission Level (dBuV/m) versus Frequency (MHz) for Radiated Emission testing below 1GHz. Two lines represent Limit and Margin, showing measured emissions below the limit.

Remark: Absolute Level = Reading Level + Factor, Margin = Absolute Level – Limit

Remark: 1. Measuring frequencies from 9 kHz to the 1 GHz, Radiated emission test from 9kHz to 30MHzwas verified, and no any emission was found except system noise floor. 2. * denotes emission frequency which appearing within the Restricted Bands specified in provision of 15.205, then the general radiated emission limits in 15.209 apply. 3. The IF bandwidth of EMI Test Receiver between 30MHz to 1GHz was 120kHz, 1 MHz for measuring above 1 GHz, below 30MHz was 10kHz. The resolution bandwidth of test receiver/spectrum analyzer is 1MHz and video bandwidth is 3MHz for peak measurement with peak detector at frequency above 1GHz. The resolution bandwidth of test receiver/spectrum analyzer is 1MHz and video bandwidth is 10Hz for Average measurement with peak detection at frequency above 1GHz. 6. When the test results of Peak Detected below the limits of Average Detected, the Average Detected is not need completed. For example: Top Channel at Fundamental 73.16dBuV/m(PK Value) <93.98(AV Limit), at harmonic 53.20 dBuV/m(PK Value) <54 dBuV/m(AV Limit), the Average Detected not need to completed. 7. For fundamental frequency, RBW>20dB Bandwidth, VBW>=3*RBW, Peak detector for PK value, RMS detector for AV value.

Test Data (Above 1 GHz)

GFSK Modulation: CH00 (2402MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

GFSK Modulation: CH39 (2441MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

GFSK Modulation: CH78 (2480MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

π/4 DQPSK Modulation: CH00 (2402MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

π/4 DQPSK Modulation: CH39 (2441MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

π/4 DQPSK Modulation: CH78 (2480MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

8DPSK Modulation: CH00 (2402MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

8DPSK Modulation: CH39 (2441MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

8DPSK Modulation: CH78 (2480MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier. Margin = Absolute Level – Limit

Band Edge

Test Limit

FCC PART 15.249(d) Emissions radiated outside of the specified frequency bands, except for harmonics, shall be attenuated by at least 50 dB below the level of the fundamental or to the general radiated emission limits in §15.209, whichever is the lesser attenuation.

Test Procedure

The band edge compliance of RF radiated emission should be measured by following the guidance in ANSI C63.10 with respect to maximizing the emission by rotating the EUT, measuring the emission while the EUT is situated in three orthogonal planes (if appropriate), adjusting the measurement antenna height and polarization etc. Set RBW to 1MHz and VBM to 3MHz to measure the peak field strength and set RBW to 1MHz and VBW to 10Hz to measure the average radiated field strength. Peak detector is for both.

Test Result

PASS

Remark: All modes were tested, only the worst result of GFSK was reported.

Band Edge Data (CH00: 2402MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier.

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier.

Band Edge Data (CH78: 2480MHz)

Horizontal:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier.

Vertical:

Remark: Factor = Antenna Factor + Cable Loss – Pre-amplifier.

6 Occupied Bandwidth

6.1 Test Setup

Same as Radiated Emission Measurement.

6.2 Test Procedure

1. The EUT was placed on a turn table which is 0.8m above ground plane.
2. Set EUT as normal operation.
3. Based on ANSI C63.10 section 6.9.2: RBW=30kHz, VBW=100kHz, Span=3MHz.
4. The useful radiated emission from the EUT was detected by the spectrum analyzer with peak detector.

6.4 Test Result

PASS

GFSK Modulation:

CH00: 2402MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for GFSK modulation at 2402MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.402000000 GHz, Occupied Bandwidth: 851.40 kHz, Total Power: 8.21 dBm, Transmit Freq Error: -6.777 kHz, OBW Power: 99.00%, x dB Bandwidth: 948.7 kHz, x dB: -20.00 dB.

CH39: 2441MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for GFSK modulation at 2441MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.441000000 GHz, Occupied Bandwidth: 851.92 kHz, Total Power: 9.33 dBm, Transmit Freq Error: -7.450 kHz, OBW Power: 99.00%, x dB Bandwidth: 951.9 kHz, x dB: -20.00 dB.

CH78: 2480MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for GFSK modulation at 2480MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.480000000 GHz, Occupied Bandwidth: 851.53 kHz, Total Power: 10.3 dBm, Transmit Freq Error: -7.702 kHz, OBW Power: 99.00%, x dB Bandwidth: 950.0 kHz, x dB: -20.00 dB.

π/4 DQPSK Modulation:

CH00: 2402MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for π/4 DQPSK modulation at 2402MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.402000000 GHz, Occupied Bandwidth: 1.1702 MHz, Total Power: 7.82 dBm, Transmit Freq Error: -7.681 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.280 MHz, x dB: -20.00 dB.

CH39: 2441MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for π/4 DQPSK modulation at 2441MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.441000000 GHz, Occupied Bandwidth: 1.1750 MHz, Total Power: 8.93 dBm, Transmit Freq Error: -5.195 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.281 MHz, x dB: -20.00 dB.

CH78: 2480MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for π/4 DQPSK modulation at 2480MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.480000000 GHz, Occupied Bandwidth: 1.1749 MHz, Total Power: 9.98 dBm, Transmit Freq Error: -6.806 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.299 MHz, x dB: -20.00 dB.

8DPSK Modulation:

CH00: 2402MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for 8DPSK modulation at 2402MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.402000000 GHz, Occupied Bandwidth: 1.1661 MHz, Total Power: 7.91 dBm, Transmit Freq Error: -7.188 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.276 MHz, x dB: -20.00 dB.

CH39: 2441MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for 8DPSK modulation at 2441MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.441000000 GHz, Occupied Bandwidth: 1.1666 MHz, Total Power: 9.09 dBm, Transmit Freq Error: -5.724 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.278 MHz, x dB: -20.00 dB.

CH78: 2480MHz

Spectrum Analyzer Screenshot Description: The screenshot shows the occupied bandwidth measurement for 8DPSK modulation at 2480MHz. The X-axis represents Frequency (GHz), and the Y-axis represents Amplitude (dBm). A curve shows the signal power distribution. Key parameters displayed include: Center Freq: 2.480000000 GHz, Occupied Bandwidth: 1.1684 MHz, Total Power: 10.0 dBm, Transmit Freq Error: -7.286 kHz, OBW Power: 99.00%, x dB Bandwidth: 1.280 MHz, x dB: -20.00 dB.

7 Antenna Requirement

Standard Applicable

For intentional device, according to FCC 47 CFR Section 15.203, 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.

Antenna Connected Construction

The antenna used in this product is a Chip Antenna. The directional gains of antenna used for transmitting is 2.0dBi.

ANTENNA:

Image Description: A close-up photograph shows a small electronic component, identified as the antenna, placed next to a ruler marked in centimeters and millimeters, illustrating its size.

8 Photo of Test

8.1 Radiated Emission

Photo Description: The image shows a typical radiated emission test setup in an anechoic chamber. The EUT is placed on a turntable, with a test antenna positioned nearby. Equipment for measurement is visible.

Photo Description: Another view of the radiated emission test setup, possibly showing a different angle or configuration, with the EUT and test antenna visible.

8.2 Conducted Emission

Photo Description: The image displays the conducted emission test setup. The EUT is placed on a table and connected to measurement equipment, including a Line Impedance Stabilization Network (LISN).