2BT5G-HEM7503 in 1 Karaoke Amplifier

This device complies with part of the FCC Rules. Operation is subject 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. Any changes or modifications 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 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 off 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 different from that to which the receiver is connected. -- Consult the dealer or an experienced radio/TV technician for help. To maintain compliance with FCC’s RF Exposure guidelines, This equipment should be installed and operated with minimum distance between cm the radiator your body: Use only the supplied antenna. FCC WARNING This device contains licence-exempt transmitter(s)/receiver(s) that comply with Innovation, Science and Economic Development Canada's licence-exempt RSS(s). Operation is subject to the following two conditions: () This device may not cause interference; and () This device must accept any interference, including interference that may cause undesired operation of the device. To maintain compliance with RF exposure guidelines, this equipment should be installed and operated with a minimum distance of cm between the radiator and your body. IC Caution: Cet appareil contient des émetteurs/récepteurs exemptés de licence qui sont conformes aux RSS exemptés de licence d'innovation, sciences et développement économique Canada. Le fonctionnement est soumis aux deux conditions suivantes: () ce dispositif ne peut pas causer d'interférence. () ce dispositif doit accepter toute interférence, y compris l'interférence qui peut causer un fonctionnement indésirable du dispositif. Pour maintenir la conformité aux directives d'exposition aux radiofréquences, cet équipement doit être installé et utilisé avec une distance minimale de cm entre le radiateur et votre corps. This radio transmitter IC:-HEM has been approved by Innovation, Science and Economic Development Canada to operate with the antenna types listed below, with the maximum permissible gain indicated. Antenna types not included in this list that have a gain greater than the maximum gain indicated for any type listed are strictly prohibited for use with this device. Antenna List： Model: .G Name: Bluetooth antenna Type: RP-SMA antenna antenna Gain: . dBi Impedance: Ω

St.Marlyn Technology Inc. 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada Attestation Statements Not Covered Entity Applicant & Not Covered Equipment To: Federal Communications Commission Date: Apr. 22, 26 7435 Oakland Mills Road, Columbia, MD 21046, USA Ref: Information Required by Section 2.911(d)(5)(i) & (ii) FCC ID: 2BT5G-HEM750 St.Marlyn Technology Inc. (“the applicant”) certifies that, as of the date of the filing of the application, the applicant is not identified on the Covered List, established pursuant to § 1.50002 of reference chapter, as an entity producing “covered” communication equipment. The equipment for which authorization is sought is not “covered” telecommunications equipment and video surveillance equipment produced by entities identified on the Commission’s Covered List that prohibited from receiving an equipment authorization pursuant to section § 2.903 of the FCC rules. Sincerely yours, Applicant Signature Printed Name: Chunxuan Zhou Title: Manager Address: 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada Tel.: (+1) 647-876-6687 Email: [email protected]

St.Marlyn Technology Inc. (50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada) 1 | P a g e Attestation Statements To: Federal Communications Commission Date: Apr. 22, 26 7435 OakZhoud Mills Road, Columbia, MD 21046, USA Subject: Attestation of Compliance with FCC Covered List Software Requirements FCC ID: [2BT5G-HEM750] Product Name: [3 in 1 Karaoke Amplifier] This letter serves as an attestation that the equipment identified above ☐ is / ☒ is not (select one) "covered" software as defined under the Federal Communications Commission (FCC) Covered List requirements, as outlined in FCC 22-84 and KDB 986446. Specifically, the undersigned certifies that the equipment for which authorization is sought: 1. Does not contain cybersecurity or anti-virus software produced or provided by Kaspersky Lab, Inc. or any of its successors, assignees, parents, subsidiaries, affiliates, or any entity that has rebranded or relabeled software produced by the aforementioned entities. 2. Does not have the capability to store, run, or deliver any software identified on the FCC Covered List, including but not limited to cybersecurity and anti-virus software. To support this attestation, the appendix evaluation documentation has been prepared and is included in the certification filing. This attestation is based on a thorough evaluation of the device's design, functionality, and software environment. The undersigned affirms that the information provided is accurate and complete to the best of their knowledge. Sincerely yours, Applicant Signature Printed Name: Chunxuan Zhou Title:Manager Address: 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada Tel.: (+1) 647-876-6687 Email: [email protected] St.Marlyn Technology Inc. (50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada) 2 | P a g e Evaluation regarding to the Covered List Software: Compliance Methodology Evaluation Process Results Device is Inherent compliance ☒ The Chipset(s) used is limited to run the Cybersecurity or anti-virus software. Compliance ☒ The Memory used is limited to run the Cybersecurity or anti-virus software. Compliance ☒ There is storage capacity limitation for store or install the Cybersecurity or anti-virus software. Compliance ☒ Operating system used is limited to run, install or deliver the Cybersecurity or anti-virus software. Compliance Device is not Inherent compliance ☐ Evaluation Based on Software Bill of Materials (SBoM) See attached “SBoM“ Note:The SBoM content is limited to the scope of covered list software (e.g. antivirus and cybersecurity software). ☐ Evaluation Based on Scan for Software on the device ☐ Evaluation Based on Filesystem scan ☐ Evaluation Based on Running software check

St.Marlyn Technology Inc. 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada (Apr. 22, 26) Federal Communications Commission Authorization and Evaluation Division 7435 OakZhoud Mills Road Columbia, MD 21046 Subject: Confidentiality Request for: FCC ID: 2BT5G-HEM750 Pursuant to Sections 0.457 and 0.459 of the Commission’s Rules, we hereby request permanent confidential treatment of the exhibits accompanying this certification application as outlined below : ⎯ Block Diagram ⎯ Schematics ⎯ Operational Description The above exhibits contain trade secrets and/or proprietary information that are not publicly available and materials that the Applicant has spent considerable efforts in developing. Public disclosure of these may be harmful to the Applicant and give an unfair advantage to competitors on the market. Sincerely, (Sincerely) Name:Chunxuan Zhou Title:Manager Address: 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5, Canada Tel.: (+1) 647-876-6687 Email: [email protected]

FCC ID: 2BT5G-HEM750 External Photos FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 BT Antenna receiving antenna Antenna receiving antenna Antenna FCC ID: 2BT5G-HEM750

Label & label location Size:20*10mm FCC ID: 2BT5G-HEM750 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

FCC ID: 2BT5G-HEM750 Internal Photos FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750 FCC ID: 2BT5G-HEM750

The test results presented in this report relate only to the object tested. This report shall not be reproduced, except in full, without the written approval of the ShenZhen STS Test Services Co., Ltd. MPE Report Report No.:STS2512462H01 Issued for St.Marlyn Technology Inc. 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Product Name: 3 in 1 Karaoke Amplifier Brand Name: Model Name: HEM-750 Series Model(s): N/A FCC ID: 2BT5G-HEM750 Test Standard: FCC 47CFR §2.1091 Page 2 of 7 Report No.: STS2512462H01 TEST REPORT Applicant’s Name ................. : St.Marlyn Technology Inc. Address ................................. : 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Manufacturer's Name ........... : St.Marlyn Technology Inc. Address ................................. : 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Product Description Product Name ........................ : 3 in 1 Karaoke Amplifier Brand Name .......................... : Model Name .......................... : HEM-750 Series Model(s) ...................... : N/A Test Standards ..................... : FCC 47CFR §2.1091 447498 D01 Interim General RF Exposure Guidance v06 The test results presented in this report relate only to the object tested. This report shall not be reproduced, except in full, without the written approval of the ShenZhen STS Test Services Co., Ltd. Date of Test ........................................... : Date of receipt of test item ...................... : 10 Dec. 2025 Date (s) of performance of tests ............. : 10 Dec. 2025 to 24 Dec. 2025 Date of Issue .......................................... : 22 Apr. 2026 Test Result .............................................. : Pass Testing Engineer : (Aaron Bu) Technical Manager : (Skylar Li) Authorized Signatory : (Bovey Yang) Page 3 of 7 Report No.: STS2512462H01 TABLE OF CONTENTS 1. GENERAL INFORMATION 5 1.1 GENERAL DESCRIPTION OF THE EUT 5 1.2 TEST FACTORY 5 2. FCC 47CFR §2.1091 REQUIREMENT 6 2.1 TEST STANDARDS 6 2.2 LIMIT 6 2.3 TEST RESULT 7 Page 4 of 7 Report No.: STS2512462H01 Revision History Rev. Issue Date Report No. Effect Page Contents 00 22 Apr. 2026 STS2512462H01 ALL Initial Issue Page 5 of 7 Report No.: STS2512462H01 1. GENERAL INFORMATION 1.1 GENERAL DESCRIPTION OF THE EUT Product Name 3 in 1 Karaoke Amplifier Brand Name Model Name HEM-750 Series Model(s) N/A Model Difference N/A Product Description The EUT is 3 in 1 Karaoke Amplifier Operation Frequency: 2402~2480 MHz Modulation Type: GFSK(1Mbps), π/4-DQPSK(2Mbps), 8DPSK(3Mbps) Antenna gain: 1.54 dBi Antenna Designation: RP-SMA antenna Power Rating AC 100-120V 50/60Hz Adapter N/A Battery N/A Hardware Version 1.0 Software Version 1.0 1.2 TEST FACTORY SHENZHEN STS TEST SERVICES CO., LTD Add. : 101, Building B, Zhuoke Science Park, No.190 Chongqing Road, ZhanChengShequ, Fuhai Sub-District, Bao’an District, Shenzhen, Guang Dong, China FCC test Firm Registration Number: 625569 IC test Firm Registration Number: 12108A A2LA Certificate No.: 4338.01 Page 6 of 7 Report No.: STS2512462H01 2. FCC 47CFR §2.1091 REQUIREMENT 2.1 TEST STANDARDS The limit for Maximum Permissible Exposure (MPE) specified in FCC 1.1310 is followed. The gain of the antennas used in the product is extracted from the Antenna data sheets provided and also the maximum total power input to the antenna is measured. Through the Friis transmission formula and the maximum gain of the antenna, we can calculate the distance, away from the product, where the limit of MPE is reached. Although the Friis Transmission formula is far field assumption, the calculated result of that is an over-prediction for near field power density. It is taken as worst case to specify the safety range. 2.2 LIMIT According to FCC 1.1310: The criteria listed in the following table shall be used to evaluate the environmental impact of the human exposure to radio-frequency (RF) radiation as specified in 1.1307 (b) Limits for Maximum Permissible Exposure (MPE) Frequency Range (MHz) Electric Field Strength (V/m) Magnetic Field Strength (A/m) Power Density (mW/cm²) Limits for Occupational / controlled Exposures 300 - 1500 -- -- F/300 3.0-30 1842/f 4.89/f *(900/f²) 1500 – 100000 -- -- 5.0 Limits for General population / Uncontrolled Exposure 300 - 1500 -- -- F/1500 1.34-30 824/f 2.19/f *(180f²) 1500 – 100000 -- -- 1.0 F= Frequency in MHz Friss Formula Friss Transmission Formula: Pd = (Pout * G) / (4*pi*r²) Where Pd = power density in mW/cm² Pout = output power to antenna in mW G = gain of antenna in linear scale Pi = 3.1416 R = Distance between observation point and the center of radiator in cm If we know the maximum gain of the antenna and the total output power to the antenna, through calculation, we will know MPE value at distance 20cm. Page 7 of 7 Report No.: STS2512462H01 2.3 TEST RESULT Tune up Mode Detector Tune up Power BT PK 3±1dBm BLE PK 2±1dBm Note: 1. The Maxinum power is less than the limit, complies with the exemption requirements 2. ERP = EIRP - 2.15 ※※※※※END OF THE REPORT※※※※※ Protocol Fre. (GHz) Separati on distance (cm) Max Tune up power (dBm) ANT Gain (dBi) Max EIRP (dBm) Max EIRP (mW) Power Density (mW/cm²) Limit (mW/ cm²) Ratio Result BT 2.402 20 4 1.54 5.54 3.58 0.00071 1 0.00071 Pass BLE 2.402 20 3 1.54 4.54 2.84 0.00057 1 0.00057 Pass

Inv erted F Antenna Specification Item An tenna Specification Model Name 2.4 G ANT Gain 2400MHz 2450MHz 2500MHz 1.33dBi 1.50dBi 1.18dBi Eff iciency 70.24% 72.27% 63.66% Impedance 50 ohm Antenna Length 67.2mm Manufact ure Actions (Zhuhai) Technology Co., Limited Antenna Dimensions Unit:mm S11 Efficiency & Gain Frequency (MHz) Efficiency (dB) Efficiency (%) Gain (dBi) 2400 -1.53 70.24 1.33 2402 -1.53 70.34 1.31 2405 -1.52 70.51 1.33 2410 -1.49 71.01 1.33 2415 -1.50 70.82 1.32 2420 -1.46 71.47 1.41 2425 -1.45 71.57 1.37 2430 -1.43 71.89 1.39 2435 -1.44 71.70 1.34 2440 -1.40 72.38 1.47 2441 -1.40 72.44 1.51 2445 -1.40 72.42 1.44 2450 -1.41 72.27 1.50 2455 -1.45 71.60 1.53 2460 -1.44 71.82 1.51 2465 -1.50 70.76 1.54 2470 -1.56 69.76 1.48 2475 -1.59 69.35 1.46 2480 -1.67 68.13 1.47 2482 -1.71 67.50 1.43 2485 -1.76 66.65 1.33 2490 -1.82 65.75 1.31 2495 -1.91 64.44 1.29 2500 -1.96 63.66 1.18 3D Radiation Pattern Front View Side View Total Response (dB) -16 2 -14 -12 -10 -8 -6 -4 -2 0 X Y Z Azimuth = 0.0 Elevation = 0.0 Roll = 0.0 Total Response (dB) -16 2 -14 -12 -10 -8 -6 -4 -2 0 X Y Z Azimuth = 0.0 Elevation = 0.0 Roll = 90.0 Configuration Front View Side View

The test results presented in this report relate only to the object tested. This report shall not be reproduced, except in full, without the written approval of the Shenzhen STS Test Services Co., Ltd. Radio Test Report Report No.:STS2512462W01 Issued for St.Marlyn Technology Inc. 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Product Name: 3 in 1 Karaoke Amplifier Brand Name: Model Name: HEM-750 Series Model(s): N/A FCC ID: 2BT5G-HEM750 Test Standards: FCC Part15.247 Page 2 of 66 Report No.: STS2512462W01 TEST REPORT Applicant’s Name ................. : St.Marlyn Technology Inc. Address ................................. : 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Manufacturer's Name .......... : St.Marlyn Technology Inc. Address ................................. : 50 West Wilmot St. Unit 10, Richmond Hill, Ontario, L4B 1M5 Canada Product Description Product Name ....................... : 3 in 1 Karaoke Amplifier Brand Name .......................... : N/A Model Name .......................... : ... : HEM-750 Series Model(s) .................... : N/A Test Standards ..................... : FCC Part15.247 Test Procedure ...................... : ANSI C63.10-2020 This device described above has been tested by STS, the test results show that the equipment under test (EUT) is in compliance with the IC requirements. And it is applicable only to the tested sample identified in the report. The test results presented in this report relate only to the object tested. This report shall not be reproduced, except in full, without the written approval of the Shenzhen STS Test Services Co., Ltd. Date of Test ........................................... : Date of receipt of test item ..................... : 10 Dec. 2025 Date (s) of performance of tests ............. : 10 Dec. 2025 to 24 Dec. 2025 Date of Issue .......................................... : 22 Apr. 2026 Test Result.............................................. : Pass Testing Engineer : (Aaron Bu) Technical Manager : (Skylar Li) Authorized Signatory : (Bovey Yang) Page 3 of 66 Report No.: STS2512462W01 Table of Contents Page 1. SUMMARY OF TEST RESULTS 6 1.1 TEST FACTORY 7 1.2 MEASUREMENT UNCERTAINTY 7 2. GENERAL INFORMATION 8 2.1 GENERAL DESCRIPTION OF THE EUT 8 2.2 DESCRIPTION OF THE TEST MODES 9 2.3 TEST SOFTWARE AND POWER LEVEL 10 2.4 BLOCK DIAGRAM SHOWING THE CONFIGURATION OF SYSTEM TESTED 10 2.5 DESCRIPTION OF NECESSARY ACCESSORIES AND SUPPORT UNITS 11 2.6 EQUIPMENTS LIST 12 RF RADIATION TEST EQUIPMENT 12 3. EMC EMISSION TEST 13 3.1 CONDUCTED EMISSION MEASUREMENT 13 3.2 TEST PROCEDURE 14 3.3 TEST SETUP 14 3.4 EUT OPERATING CONDITIONS 14 3.5 TEST RESULTS 15 4. RADIATED EMISSION MEASUREMENT 17 4.1 RADIATED EMISSION LIMITS 17 4.2 TEST PROCEDURE 19 4.3 TEST SETUP 20 4.4 EUT OPERATING CONDITIONS 20 4.5 FIELD STRENGTH CALCULATION 21 4.6 TEST RESULTS 22 5. CONDUCTED SPURIOUS & BAND EDGE EMISSION 33 5.1 LIMIT 33 5.2 TEST PROCEDURE 33 5.3 TEST SETUP 33 5.4 EUT OPERATION CONDITIONS 33 5.5 TEST RESULTS 33 6. POWER SPECTRAL DENSITY TEST 34 6.1 LIMIT 34 6.2 TEST PROCEDURE 34 Page 4 of 66 Report No.: STS2512462W01 Table of Contents Page 6.3 TEST SETUP 34 6.4 EUT OPERATION CONDITIONS 34 6.5 TEST RESULTS 34 7. BANDWIDTH TEST 35 7.1 LIMIT 35 7.2 TEST PROCEDURE 35 7.3 TEST SETUP 35 7.4 EUT OPERATION CONDITIONS 35 7.5 TEST RESULTS 35 8. PEAK OUTPUT POWER TEST 36 8.1 LIMIT 36 8.2 TEST PROCEDURE 36 8.3 TEST SETUP 36 8.4 EUT OPERATION CONDITIONS 36 8.5 TEST RESULTS 36 9. ANTENNA REQUIREMENT 37 9.1 STANDARD REQUIREMENT 37 9.2 EUT ANTENNA 37 APPENDIX 1-TEST DATA 38 APPENDIX 2- EUT TEST PHOTO 66 Page 5 of 66 Report No.: STS2512462W01 Revision History Rev. Issue Date Report No. Effect Page Contents 00 22 Apr. 2026 STS2512462W01 ALL Initial Issue Page 6 of 66 Report No.: STS2512462W01 1. SUMMARY OF TEST RESULTS Test procedures according to the technical standards: KDB 558074 D01 15.247 Meas Guidance v05r02. FCC Part 15.247,Subpart C Standard Section Test Item Judgment Remark 15.207 Conducted Emission PASS -- 15.247 (a)(2) 6dB Bandwidth PASS -- 15.247 (b)(3) Output Power PASS -- 15.209 Radiated Spurious Emission PASS -- 15.247 (d) Conducted Spurious & Band Edge Emission PASS -- 15.247 (e) Power Spectral Density PASS -- 15.205 Restricted bands of operation PASS -- Part 15.247(d)/ Part 15.209(a) Band Edge Emission PASS -- 15.203 Antenna Requirement PASS -- Note: (1) ‘N/A’ denotes test is not applicable in this Test Report. (2) All tests are according to ANSI C63.10-2020. Page 7 of 66 Report No.: STS2512462W01 1.1 TEST FACTORY SHENZHEN STS TEST SERVICES CO., LTD Add. : 101, Building B, Zhuoke Science Park, No.190 Chongqing Road, ZhanChengShequ, Fuhai Sub-District, Bao’an District, Shenzhen, Guang Dong, China FCC test Firm Registration Number: 625569 IC test Firm Registration Number: 12108A A2LA Certificate No.: 4338.01 1.2 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 %. No. Item Uncertainty 1 RF output power, conducted ±0.751dB 2 Unwanted Emissions, conducted ±2.888dB 3 All emissions, radiated 9K-30MHz ±2.48dB 4 All emissions, radiated 30M-1GHz ±2.52dB 5 All emissions, radiated 1G-18GHz ±3.48dB 6 All emissions, radiated>18GHz ±4.18dB 7 Conducted Emission (9KHz-150KHz) ±2.48dB 8 Conducted Emission (150KHz-30MHz) ±2.52dB 9 Occupied Channel Bandwidth ±3.6% 10 Power Spectral Density, conducted ±1.214dB 11 Duty Cycle ±3.2% Page 8 of 66 Report No.: STS2512462W01 2. GENERAL INFORMATION 2.1 GENERAL DESCRIPTION OF THE EUT Product Name 3 in 1 Karaoke Amplifier Brand Name Model Name HEM-750 Series Model(s) N/A Model Difference N/A Product Description The EUT is a 3 in 1 Karaoke Amplifier Operation Frequency: 2402~2480 MHz Modulation Type: GFSK Radio Technology: BLE Bluetooth Configuration: 5.0 Number Of Channel: 40 Antenna Type: RP-SMA antenna Antenna Gain…

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Page 1 of 2 FCC ID: 2BT5G-HEM750 Conducted emissions 30MHz-1GHz Page 2 of 2 FCC ID: 2BT5G-HEM750 Spurious emissions