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48mm Square Internal Magnet Speaker – 4Ohms 5W
[Speakers] 48mm Square Internal Magnet Speaker – 4Ω 5W The 48mm Square Internal Magnet Speaker is a compact full-range audio driver designed for clear and efficient sound reproduction in space-constrained applications. With a 4Ω impedance and 5W power rating, this speaker is suitable for Bluetooth speakers, portable audio systems, DIY speaker projects and embedded electronic devices. Its square frame allows convenient mounting inside compact enclosures and panels. ⭐ Key Features Compact square speaker design 4Ω impedance 5W power rating Internal magnet construction Full-range audio output Compact size for space-limited applications Easy to install inside speaker enclosures Suitable for DIY and commercial audio projects Lightweight and practical design 📋 Technical Specifications Speaker Type: Internal Magnet Speaker Shape: Square Speaker Size: 48mm class Model: 4Ω 5W Impedance: 4Ω Power Rating: 5W Magnet Type: Internal Magnet Audio Type: Full-range Mounting Type: Panel / Enclosure Mount Dimensions: 47 × 29 × 23mm Application: Compact audio systems, DIY electronics and portable speakers 🔧 Applications Bluetooth speaker systems Portable speakers DIY speaker projects Compact audio enclosures Embedded audio systems Intercom systems Alert and notification devices Educational electronics projects Consumer electronic devices Custom audio projects 🛠️ Installation Connect the speaker to a compatible amplifier with a 4Ω output. Ensure the amplifier's output power is suitable for the speaker's 5W rating. Mount the speaker securely inside the enclosure to reduce unwanted vibration. Observe correct speaker polarity when connecting multiple speakers. 📦 Package Includes 1 × 48mm Square Internal Magnet Speaker Impedance: 4Ω Power: 5W ⚠️ Precautions Do not exceed the 5W rated power for prolonged operation. Use a compatible 4Ω amplifier. Avoid short-circuiting the speaker terminals. Keep away from moisture, excessive heat and physical damage. Ensure proper mounting to minimize vibration and unwanted noise. Actual sound quality depends on the amplifier, enclosure and application.
Out of stockGold AP-55 TPA3116D2 2×50W Bluetooth Stereo Digital Amplifier Board with USB, TF Card, FM & Remote
[Amplifier Board] Gold AP-55 TPA3116D2 2×50W Bluetooth Stereo Digital Amplifier Board with USB, TF Card, FM & Remote The Gold AP-55 is a compact Class-D stereo digital audio amplifier board based on the TPA3116D2 amplifier IC, designed for DIY Bluetooth speakers, home audio systems, portable speakers, bookshelf speakers, multimedia systems, and custom audio projects. Available product listings consistently identify the AP-55 as a dual-channel 50W + 50W amplifier, with a DC input range around 8–24V or 12–24V depending on the listing/version. The AP-55 combines the power amplifier with a multimedia player supporting Bluetooth 5.0, USB, TF/SD card, FM radio and AUX input. The Bluetooth device name is reported as GD-82EM, while the FM tuner covers 87.5–108.0MHz. It also includes an infrared remote control and a digital display for convenient operation. The TPA3116D2 Class-D amplifier provides efficient stereo amplification, making the board suitable for building compact but powerful audio systems. One detailed listing specifies support for 4Ω–8Ω speakers, with the commonly advertised maximum output of 50W per channel. ⭐ Key Features Gold AP-55 amplifier module TPA3116D2 Class-D amplifier IC 50W + 50W dual-channel stereo output Supports 4Ω–8Ω speakers Bluetooth 5.0 wireless audio Bluetooth device name: GD-82EM Built-in USB music player Built-in TF / SD card player Built-in FM radio FM frequency range 87.5–108.0MHz 3.5mm AUX input Infrared remote control Digital display Supports MP3 / WMA / WAV Power-off memory function Remembers the previous song and volume Compact design for DIY speaker projects High-efficiency Class-D amplification 📋 Technical Specifications Product Type: Stereo Class-D Digital Amplifier Board Model: Gold AP-55 Amplifier IC: TPA3116D2 Amplifier Class: Class-D Number of Channels: 2 / Stereo Output Power: 50W + 50W Maximum Total Output: 100W Speaker Impedance: 4Ω–8Ω Input Voltage: DC 8–24V (some listings specify 12–24V; verify the exact board version before use) Bluetooth Version: 5.0 Bluetooth Name: GD-82EM Bluetooth Range: Up to approximately 10–15m under suitable conditions Audio Formats: MP3 / WMA / WAV USB Support: Yes TF/SD Card Support: Yes FM Radio: Yes FM Frequency: 87.5–108.0MHz AUX Input: 3.5mm / Wired Audio Input Remote Control: IR Remote Remote Range: Approximately 4–7m Display: Digital Display Power-Off Memory: Yes Memory Function: Last song and volume Audio Input Modes: Bluetooth / USB / TF Card / FM / AUX Output: Dual-Channel Stereo Efficiency: Greater than 90% according to one detailed listing SNR: Approximately 102dB according to one detailed listing Distortion: Below 0.1% at normal listening levels according to one detailed listing Board Size: Approximately 70 × 50 × 20mm with shell, according to one listing 🎵 Audio & Playback Functions The AP-55 can switch between Bluetooth, USB, TF/SD Card, FM Radio and AUX sources. When Bluetooth mode is selected, users can pair a phone or other compatible device with GD-82EM. USB and TF/SD cards can be used for local music playback, while AUX provides a wired audio input. 📻 FM Radio The built-in FM tuner supports the 87.5–108.0MHz broadcast band. FM stations can be searched and selected using the onboard controls or remote control. 🎛️ Controls & Remote The module provides controls for functions such as previous track, next track, volume up, volume down, play/pause, mode selection and FM station selection. The infrared remote provides additional wireless control of playback, volume, mode and other supported functions. 🔧 Applications DIY Bluetooth Speakers High-Power Bluetooth Speaker Projects Portable Speaker Systems Bookshelf Speaker Systems Home Audio Projects Multimedia Speaker Systems USB MP3 Speaker Systems TF/SD Card Music Players FM Radio Speaker Projects Car Audio Projects Custom Wooden Speaker Cabinets Desktop Audio Systems Electronics DIY Projects 🛠️ Installation Connect a suitable DC power supply within the specified voltage range and observe the correct polarity. Connect the left and right speaker outputs to compatible 4Ω–8Ω speakers. Select Bluetooth, USB, TF/SD, FM or AUX according to the desired audio source. For maximum advertised output, a suitable 24V high-current power supply is recommended by one vendor; at lower supply voltages, available output power will be lower. 📦 Package Includes 1 × Gold AP-55 TPA3116D2 2×50W Bluetooth Amplifier Board 1 × IR Remote Control 1 × Required Connecting Wires/Cables (package contents may vary by seller/version) ⚠️ Precautions Verify the exact input voltage requirement of your AP-55 version before powering it. Do not exceed 24V DC where the board specification limits input to 24V. Check power polarity carefully before connection. Use speakers with a compatible 4Ω–8Ω impedance. Do not short-circuit the speaker output terminals. Ensure adequate ventilation during high-power operation. Use a suitable high-current power supply for high-output operation. Do not connect the speaker outputs together or directly to ground. Keep the board away from moisture and conductive materials. Incorrect wiring or excessive voltage can permanently damage the amplifier IC.
45mm 1.75-Inch 4Ohms 3W Internal Magnet Speaker with Frame
[Speakers] 45mm Internal Magnet Speaker with Frame – 4Ω 3W 45×23×23mm The 45mm Internal Magnet Speaker with Frame (1.75-Inch) is a compact and efficient audio driver designed for DIY electronics, portable audio devices, multimedia systems, toys, alarms, intercoms, and embedded audio applications. Featuring an internal magnet structure and durable mounting frame, this speaker provides clear and stable sound output while maintaining a compact form factor. With a compact size of 45×23×23mm, 4Ω impedance, and 3W power rating, this speaker is suitable for small amplifier projects and electronic devices where space is limited. Its built-in frame allows convenient installation in custom enclosures, panels, and electronic products. ⭐ Key Features 45mm (1.75-Inch) speaker size 4Ω impedance 3W power rating Internal magnet design Durable mounting frame Compact 45×23×23mm construction Clear and stable sound output Lightweight and space-saving Suitable for low-power audio applications Easy to install in custom enclosures Ideal for DIY, repair and OEM applications 📋 Technical Specifications Product Type: Internal Magnet Speaker Speaker Size: 45mm (1.75 Inch) Dimensions: 45 × 23 × 23mm Impedance: 4Ω Power Rating: 3W Magnet Type: Internal Magnet Frame Type: With Mounting Frame Speaker Type: Dynamic Full Range Speaker Audio Type: Mini Full Range Speaker Mounting: Frame / Panel Mount Application: Compact Audio & Embedded Electronics 🔧 Applications DIY Speaker Projects Portable Audio Devices Bluetooth Speaker Projects Multimedia Speaker Systems Alarm Systems Toys and Sound Modules Intercom Systems Embedded Electronics Educational Electronics Kits Replacement Speaker Repairs Smart Gadgets OEM Product Manufacturing Mini Amplifier Projects 🛠️ Installation Mount the speaker securely inside the required enclosure or panel using its mounting frame. Connect it to a compatible amplifier with an output suitable for 4Ω speakers and a power rating appropriate for the 3W speaker. Proper mounting helps reduce unwanted vibration and improves overall sound performance. 📦 Package Includes 1 × 45mm Internal Magnet Speaker with Frame – 4Ω 3W ⚠️ Precautions Match the 4Ω impedance with the amplifier output. Do not exceed the 3W rated power. Do not apply direct DC voltage to the speaker. Ensure correct wiring polarity during installation. Avoid exposure to moisture and excessive dust. Mount securely to prevent vibration and unwanted noise. Do not apply physical pressure to the speaker cone or diaphragm. Use a compatible audio amplifier module for proper operation.
2 Inch 4 Ohms 5Watt Internal Magnet Speaker with Frame
[Speakers] 2-Inch Internal Magnet Speaker with Frame – 53×29×23mm 4Ω 5W The 2-Inch Internal Magnet Speaker with Frame is a compact and efficient audio driver designed for DIY electronics, portable audio devices, alarms, toys, embedded systems, and other space-constrained applications. Featuring an internal magnet design and durable frame construction, this speaker provides clear and balanced sound output while maintaining a compact footprint. With dimensions of 53×29×23mm, 4Ω impedance, and a 5W power rating, this speaker is suitable for small amplifier projects and electronic devices requiring a compact audio solution. The mounting frame makes installation convenient in custom enclosures and equipment. ⭐ Key Features 2-Inch compact speaker design Internal magnet structure 4Ω impedance 5W power rating Durable metal frame construction Clear and balanced sound output Compact and space-saving design Easy mounting with frame and screw slots Suitable for low and medium-power audio applications Ideal for DIY and OEM applications 📋 Technical Specifications Product Type: Dynamic Internal Magnet Speaker Speaker Size: 2 Inch Dimensions: 53 × 29 × 23mm Impedance: 4Ω Power Rating: 5W Magnet Type: Internal Magnet Magnet Material: Ferrite Shape: Rectangular Frame Type: Metal Frame Cone Material: Paper / Mylar Diaphragm depending on variant Speaker Type: Full Range / Dynamic Speaker Mounting: Frame with Screw Slots Application: Compact Audio & Embedded Electronics 🔧 Applications DIY Speaker Projects Portable Audio Devices Bluetooth Speaker Projects Alarm Systems Toys and Sound Modules Intercom Systems Embedded Electronics Educational Electronics Kits Replacement Speaker Repairs Smart Gadgets OEM Product Manufacturing Mini Amplifier Projects 🛠️ Installation Connect the speaker to a compatible amplifier output matching the speaker's 4Ω impedance and 5W power rating. Secure the speaker firmly using the mounting frame to reduce unwanted vibration and noise during operation. 📦 Package Includes 1 × 2-Inch Internal Magnet Speaker with Frame – 4Ω 5W ⚠️ Precautions Match the 4Ω impedance with the amplifier output. Do not exceed the 5W rated power. Avoid applying direct DC voltage to the speaker. Avoid exposure to moisture and excessive humidity. Mount the speaker securely before operation. Do not apply physical pressure to the speaker cone or diaphragm. Avoid short circuits at the speaker terminals. Keep the speaker away from excessive heat and magnetic interference.
2.25-Inch 8ohms 8W Full Range Speaker for Compact Audio Applications
[Speakers] 2.25-Inch 8Ω 8W Full Range Speaker for Compact Audio Applications The 2.25-Inch 8Ω 8W Full Range Speaker is a compact and efficient audio driver designed for small electronic and embedded sound applications. Featuring an 8Ω impedance and 8W power rating, this speaker delivers clear and balanced sound output while maintaining low power consumption and excellent efficiency. Its compact size makes it ideal for projects where installation space is limited, including portable speakers, DIY electronics, toys, alarm systems, intercom devices, and mini speaker enclosures. The full-range design allows it to reproduce a broad range of audio frequencies, making it suitable for both voice and music playback applications. Built with durable materials and designed for reliable long-term performance, this speaker is an excellent choice for electronics hobbyists, engineers, and product developers working on custom audio projects. ⭐ Key Features 2.25-Inch compact speaker driver 8Ω impedance 8W power rating Full-range audio reproduction Clear and balanced sound output Lightweight and compact design Easy to mount in enclosures and panels Suitable for low to medium-power audio applications Durable construction for long-term use Ideal for DIY and embedded audio systems 📋 Technical Specifications Product Type: Full Range Speaker Speaker Size: 2.25 Inch Impedance: 8Ω Power Rating: 8W Speaker Type: Full Range Mounting Type: Enclosure / Panel Mount Application Type: Audio Output 🔧 Applications Portable Speaker Systems DIY Audio Projects Bluetooth Speaker Modules Toys and Educational Kits Alarm and Notification Systems Embedded Electronic Devices Mini Amplifiers and Sound Modules Intercom Systems Robotics Projects Custom Speaker Enclosures ⚠️ Precautions Do not exceed the 8W rated power. Use an amplifier compatible with an 8Ω speaker load. Avoid exposure to moisture and excessive dust. Mount securely to minimize vibration and distortion. Do not apply direct pressure on the speaker cone. 📦 Package Includes 1 × 2.25-Inch 8Ω 8W Full Range Speaker
57mm (2.25-Inch) Internal Magnet Speaker 4Ohms 3W Full Range Audio Speaker
[Speakers] 57mm (2.25-Inch) Internal Magnet Speaker – 4Ω 3W Full Range Audio Speaker The 57mm (2.25-Inch) Internal Magnet Speaker is a compact and reliable full-range audio speaker designed for DIY electronics, multimedia devices, embedded sound systems, and portable audio applications. Featuring a 4Ω impedance and 3W power rating, this speaker delivers clear and balanced sound output while maintaining a slim and lightweight design. Its internal magnet structure provides a compact profile, making it ideal for applications where installation space is limited. The durable mounting frame allows easy integration into speaker enclosures, control panels, intercom systems, audio modules, and custom electronic projects. Designed for consistent audio performance, this speaker is suitable for voice playback, music, alerts, and general audio output in both portable and embedded electronic devices. ⭐ Key Features 57mm (2.25-Inch) compact speaker 4Ω impedance 3W power rating Internal magnet design Full-range audio reproduction Built-in mounting frame Clear and balanced sound output Compact and lightweight construction Easy installation in custom enclosures Suitable for portable and embedded audio applications Ideal for DIY electronics and speaker projects 📋 Technical Specifications Product Type: Internal Magnet Speaker Speaker Size: 57mm (2.25 Inch) Impedance: 4Ω Power Rating: 3W Speaker Type: Full Range Magnet Type: Internal Magnet Frame Type: With Mounting Frame Mounting: Frame / Panel Mount Application: Embedded Audio Systems 🔧 Applications DIY Electronics Projects Audio Modules & Music Players Intercom and Communication Systems Toys and Educational Devices Portable Audio Systems Alarm and Notification Devices Embedded Audio Applications Mini Speaker Enclosures Multimedia Devices Robotics and Automation Projects ⚠️ Precautions Do not exceed the 3W rated power. Use an amplifier compatible with a 4Ω speaker load. Ensure proper wiring polarity during installation. Avoid exposure to moisture and dust. Mount securely to reduce vibration noise. Do not apply direct pressure on the speaker cone. 📦 Package Includes 1 × 57mm (2.25-Inch) 4Ω 3W Internal Magnet Full Range Speaker
45mm (1.75-Inch) Internal Magnet Speaker 2 Ohms 10W Full Range Audio Speaker
[Speakers] 45mm (1.75-Inch) Internal Magnet Speaker – 2Ω 10W Full Range Audio Speaker The 45mm (1.75-Inch) Internal Magnet Speaker is a compact and powerful audio driver designed for DIY electronics, portable speakers, multimedia devices, toys, embedded audio systems, and custom speaker enclosures. Featuring a 2Ω impedance and 10W power rating, this speaker provides strong audio output when paired with a compatible amplifier. Its internal magnet design provides a compact profile while maintaining efficient magnetic performance. The built-in mounting frame makes installation easy in custom enclosures and electronic devices. With its 2Ω low-impedance configuration, this speaker is suitable for compatible Class-D amplifier modules where higher output power is required from a compact speaker driver. ⭐ Key Features 45mm (1.75-Inch) compact speaker 2Ω impedance 10W power rating Internal magnet design Full-range audio reproduction Compact and lightweight construction Built-in mounting frame Clear and powerful sound output Easy to install in custom enclosures Suitable for portable and embedded audio applications Ideal for DIY speaker projects 📋 Technical Specifications Product Type: Internal Magnet Speaker Speaker Size: 45mm (1.75 Inch) Impedance: 2Ω Power Rating: 10W Speaker Type: Full Range Magnet Type: Internal Magnet Frame Type: Mounting Frame Mounting: Frame / Panel Mount Application: Embedded & Portable Audio 🔧 Applications DIY Bluetooth Speaker Projects Portable Speaker Systems Mini Audio Amplifiers Multimedia Devices Toys and Educational Kits Intercom Systems Alarm and Notification Systems Embedded Audio Devices Custom Speaker Enclosures Robotics Projects Electronic Projects ⚠️ Precautions Use an amplifier that supports a 2Ω load. Do not exceed the 10W rated power. Check amplifier output impedance before connecting. Observe correct speaker polarity during installation. Avoid excessive mechanical pressure on the speaker cone. Keep away from moisture and excessive dust. Mount securely to minimize unwanted vibration and distortion. 📦 Package Includes 1 × 45mm (1.75-Inch) 2Ω 10W Internal Magnet Full Range Speaker
2.25 Inch 4 Ohm 10 Watt Full Range Speaker with Neodymium Magnet
[Speakers] 2.25-Inch Speaker Driver • 4 Ohm Impedance • 10W Power Rating • Neodymium Magnet • Compact Full Range Audio Speaker The 2.25 Inch 4 Ohm 10 Watt Full Range Speaker with Neodymium Magnet is a compact and high-performance speaker driver designed for portable audio systems, DIY speaker projects, multimedia devices, embedded electronics, and custom sound enclosures. Featuring a powerful neodymium magnet, this speaker delivers clear vocals, balanced midrange, and improved bass response while maintaining a lightweight and compact design. With a 4 ohm impedance and 10 watt power rating, the speaker is suitable for use with small audio amplifiers, Bluetooth amplifier modules, DIY portable speakers, mini sound systems, toys, alarm systems, educational kits, and embedded electronic devices. The full-range design allows it to reproduce a wide spectrum of audio frequencies without requiring additional tweeters for many compact applications. Its durable construction and lightweight neodymium magnet assembly make it ideal for applications where both performance and space efficiency are important. ⭐ Features Compact 2.25-inch full range speaker Powerful neodymium magnet 4 ohm impedance 10 watt power rating Clear and balanced sound output Enhanced vocal clarity and midrange performance Lightweight and compact construction Easy to mount in custom enclosures Suitable for portable and embedded audio systems Ideal for DIY electronics and audio projects 📋 Technical Specifications Product Type: Full Range Speaker Driver Speaker Size: 2.25 Inch Impedance: 4 Ohm Power Rating: 10 Watt Magnet Type: Neodymium Speaker Type: Full Range Mounting Type: Enclosure / Panel Mount Application Type: Audio Output Frame Material: Metal Cone Material: Paper Composite Color: Black 🔧 Applications Suitable for: Portable Speaker Systems Bluetooth Speakers DIY Audio Projects Mini Sound Systems Multimedia Devices Toys and Educational Kits Alarm and Notification Systems Embedded Electronic Devices Mini Amplifiers Sound Modules Intercom Systems Custom Speaker Enclosures Robotics and Electronics Projects 📦 Package Includes 1 × 2.25 Inch 4 Ohm 10 Watt Full Range Speaker with Neodymium Magnet ⚠️ Precautions Do not exceed the 10W rated power. Use an amplifier compatible with 4 ohm speakers. Avoid exposure to moisture, water, and excessive dust. Mount the speaker securely to minimize unwanted vibration. Do not apply direct pressure to the speaker cone or surround.
Passive Radiator Bass Diaphragm Rubber Speaker Vibration Plate for DIY Speakers
[Passive Radiator] 🔊 Oval, Square & Round Passive Radiator Bass Diaphragm Rubber Speaker Vibration Plate for DIY Speakers Deep Bass Enhancement • Passive Design • No External Power Required • Ideal for DIY Speaker Projects The Rubber Passive Radiator Bass Diaphragm is a high-quality auxiliary bass vibration plate designed to significantly improve the low-frequency response of speaker systems. Available in Oval, Square, and Round shapes with multiple sizes, this passive radiator enhances bass performance without requiring additional power or amplifier channels. Unlike conventional speakers, a passive radiator does not contain a voice coil or magnet. Instead, it utilizes the air pressure generated by the active speaker driver to vibrate, producing deeper, richer bass while minimizing distortion and unwanted cabinet resonance. Manufactured using premium rubber and durable ABS materials, these passive radiators provide excellent flexibility, durability, and long service life. They are ideal for upgrading Bluetooth speakers, portable speakers, multimedia speakers, subwoofers, soundbars, and custom DIY audio projects. Whether you're repairing an existing speaker or building a custom enclosure, these passive bass diaphragms help deliver powerful low-frequency performance while maintaining compact enclosure sizes. ⭐ Features Premium quality rubber passive radiator Available in Oval, Square & Round shapes Produces deep and powerful bass response No power supply or wiring required Improves low-frequency performance Reduces speaker distortion Durable rubber suspension Lightweight and compact design Easy to install Ideal for DIY speaker upgrades and repairs 📋 Technical Specifications Product Type: Passive Radiator Bass Diaphragm Material: Rubber + ABS Plastic+Metal Shape: Oval / Square / Round (Depending on Selected Variant) Available Sizes: Multiple Sizes (2040 to 6090 Series) Operation: Passive (No Voice Coil or Magnet) Power Requirement: None Installation Type: Speaker Cabinet Mount Application: Low Frequency Bass Enhancement Color: Black 🔧 Applications Suitable for: Bluetooth Speakers Portable Speakers DIY Speaker Projects Multimedia Speakers Home Audio Systems Bookshelf Speakers Soundbars Subwoofers Wireless Speakers Audio System Repairs Custom Speaker Cabinets DIY Audio Enclosures 📦 Package Includes 1 × Passive Radiator Bass Diaphragm (Size & Shape as Selected) ⚠️ Note This is a passive radiator only and does not contain a voice coil, magnet, or electrical terminals. Product images are for reference only. The actual product may vary slightly in appearance depending on the selected size, shape, or manufacturing batch.
Keltron 3300uF 25V Radial Electrolytic Capacitor High Performance Capacitor
[Through Hole Capacitor] The Keltron 3300uF 25V Electrolytic Capacitor is a high-performance aluminum electrolytic capacitor designed for energy storage, voltage filtering, and ripple suppression applications. It is widely used in power supply circuits, audio amplifiers, inverter systems, battery chargers, and industrial electronics. In addition, the capacitor provides excellent filtering capability by reducing voltage fluctuations and unwanted electrical noise. As a result, it helps improve circuit stability and enhances overall system performance. Because of its 3300uF high capacitance value, the capacitor is ideal for smoothing DC power rails and handling transient current demands. Furthermore, the 25V DC voltage rating makes it suitable for a variety of low-voltage electronic applications. The radial lead design allows easy PCB installation and secure mounting. Moreover, Keltron capacitors are known for their dependable quality, stable electrical characteristics, and long operational life. This capacitor is commonly used in audio amplifier power supplies, SMPS circuits, LED power supplies, inverter systems, battery chargers, and DIY electronics projects. 🔹 Key Features Genuine Keltron capacitor High capacitance 3300uF value Rated voltage of 25V DC Excellent ripple filtering performance Suitable for audio and power supply circuits Low leakage current Long operational life Radial lead through-hole design Reliable and stable performance 🔹 Technical Specifications Brand: Keltron Product Type: Electrolytic Capacitor Capacitor Type: Aluminum Electrolytic Capacitance: 3300uF Rated Voltage: 25V DC Tolerance: ±20% Mounting Type: Through-Hole (Radial Lead) Polarized: Yes Lead Type: Radial Operating Temperature: Up to 105°C (Series Dependent) Application: Filtering, Decoupling, Energy Storage 🔹 Applications This capacitor is suitable for: Audio amplifier circuits Power supply filtering SMPS circuits Inverter systems Battery chargers LED driver circuits Industrial electronics DIY electronics projects Electronic repair applications 🔹 Package Includes 1 × Keltron 3300uF 25V Radial Electrolytic Capacitor
Portable USB Bluetooth Audio Music Receiver Dongle Adapter – Wireless Audio Receiver
[Audio Receiver] The Portable USB Bluetooth Audio Music Receiver Dongle Adapter instantly converts any car stereo, home speaker, PC speakers, or audio system into a wireless Bluetooth-enabled music receiver. Simply plug the dongle into a USB power source, connect its audio output to AUX, and enjoy seamless wireless music streaming from your smartphone, tablet, or laptop. This compact Bluetooth receiver delivers crisp, high-quality audio with stable transmission—making it perfect for cars without built-in Bluetooth, wired speakers, home audio systems, and portable sound setups. It supports all Bluetooth-enabled devices and offers quick pairing, low power consumption, and wide compatibility. Whether you're upgrading your car audio or converting old speakers into wireless ones, this USB Bluetooth receiver provides an easy and affordable solution. ✅ Features Convert any speaker or car stereo into a Bluetooth audio receiver Provides high-quality wireless music streaming from mobile, tablet, or laptop USB-powered – plug into car charger, power bank, or USB port Stable Bluetooth connection with fast pairing Compatible with car stereos, home speakers, multimedia systems, and amplifiers Ultra-compact, lightweight, and easy to carry Supports all major Bluetooth audio devices No drivers required – plug & play operation **** 3.5mm jack or cable not included***** 📘 Specifications Device Type: USB Bluetooth Audio Receiver Bluetooth Version: Standard high-quality audio support Input Power: USB 5V Output: 3.5mm AUX audio Transmission Distance: Approx. 8–10 meters Compatibility: Android, iOS, laptops, tablets, car stereos, speakers, amplifiers Usage: Car audio upgrade, home audio wireless streaming, mobile speaker enhancement Design: Compact & portable
BC557 PNP General Purpose Transistor – TO-92-3 Package
[Transistor] BC557 PNP General Purpose Transistor – TO-92-3 Package BC557 PNP General Purpose Transistor 45V 100mA BC557 is a semiconductor device used to amplify or switch electronic signals and electrical power. This transistor composed of semiconductor material usually with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor’s terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. This product is known as BC557, BC557BTA, BC557ATA, BC557BTF, BC557B, BC557C, BC557A, BC557CBK, BC557BBK Features: Low current (max. 100 mA) Low voltage (max. 65 V). Low error voltage Fast switching speed Full-voltage operation High power and current handling capability Features/Specs: Product Type: BJTs – Bipolar Transistors Transistor Polarity: PNP Configuration: Single Collector- Emitter Voltage VCEO Max: 45 V Collector- Base Voltage VCBO: 50 V Emitter- Base Voltage VEBO: 5 V Pd – Power Dissipation: 500 mW Gain Bandwidth Product fT: 100 MHz DC Collector/Base Gain hFE Min: 125 DC Current Gain hFE Max: 125 at 2 mA, 5 V Minimum Operating Temperature: – 65°C Maximum Operating Temperature: + 150°C Mounting Style: Through Hole Package/Case: TO-92-3 Applications: Driver Modules like Relay Driver, LED driver etc.. Amplifier modules like Audio amplifiers, signal Amplifier etc.. Darlington pair Datasheet: BC557 PNP Transistor Package Includes: 1 x BC557 PNP General Purpose Transistor – TO-92-3 Package Note: Product Images are shown for illustrative purposes only and may differ from actual product
ZK-MT21 bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
[Amplifier Board] ZK-MT21 2.1 Channel Bluetooth 5.0 Audio Amplifier Module – 50W × 2 + 100W Subwoofer The ZK-MT21 2.1 Channel Bluetooth Audio Amplifier Module is a compact high-power stereo amplifier board designed for DIY Bluetooth speaker and home audio projects. It supports Bluetooth 5.0 and AUX audio input and provides dedicated left, right and subwoofer channels with adjustable volume, bass, treble, subwoofer volume and subwoofer frequency controls. With a suitable DC power supply and properly matched speakers, the module can deliver up to 50W + 50W for the left/right channels and up to 100W for the subwoofer channel. The board includes protection against reverse connection, overheating, overcurrent and short circuit. ⭐ Key Features Model: ZK-MT21 2.1 channel stereo audio amplifier Bluetooth 5.0 wireless audio input Bluetooth transmission distance up to approximately 15 meters under suitable conditions AUX wired audio input Left + Right + Subwoofer output Output up to 50W × 2 + 100W subwoofer Supports 4Ω–8Ω speakers Adjustable main volume Adjustable bass and treble for left/right channels Adjustable subwoofer volume Adjustable subwoofer frequency Subwoofer frequency adjustment range 20Hz–200Hz Reverse-polarity protection Overheat protection Overcurrent protection Short-circuit protection Compact amplifier board design Suitable for DIY Bluetooth speaker projects 📋 Technical Specifications Product Name: 2.1 Channel Audio Amplifier Module Model: ZK-MT21 Bluetooth Version: 5.0 Bluetooth Range: Approximately 15m Bluetooth Shielding: No shielding Audio Input: AUX + Bluetooth Channel: 2.1 Input Sensitivity: 500mV Amplifier Chip Solution: Domestic power amplifier chip Power Supply: DC 12–24V Recommended Supply Current: 5A or above Left Channel Output: <50W Right Channel Output: <50W Subwoofer Output: <100W Total Configuration: 50W × 2 + 100W Compatible Speaker Impedance: 4–8Ω Recommended Speaker Power: 20–100W Subwoofer Frequency Adjustment: 20Hz–200Hz Product Dimensions: 93 × 90 × 22mm Package Weight: Approximately 185g Protection: Reverse connection, overheat, overcurrent and short circuit ⚠️ Power Supply Warning:Do not connect this module directly to a 24V battery pack. Use a suitable regulated DC power supply as specified for the module. 🎛️ Control Functions MAIN-VOLUME: Controls the overall volume of the left, right and subwoofer channels. R&L CHANNEL-BASS: Adjusts bass level for the left and right channels. R&L CHANNEL-TREBLE: Adjusts treble level for the left and right channels. SUBWOOFER-VOLUME: Controls the subwoofer volume. SUBWOOFER-FREQ: Adjusts the subwoofer cutoff frequency from approximately 20Hz to 200Hz. 🔊 Speaker Selection Left and right channels can be connected to 4Ω–8Ω full-range or mid/high-frequency speakers. Recommended speaker power is 20W–100W. The subwoofer output should be connected to a suitable subwoofer speaker, not a regular full-range speaker. The subwoofer should have suitable low-frequency performance, with the source information recommending a frequency capability of at least 50Hz. Speaker impedance and power should be matched correctly with the amplifier. 🔌 Power Supply Selection The power supply is important for achieving proper amplifier performance and sound quality. A power supply with excessive ripple may increase background noise. Recommended supply: 18V / 19V / 24V with current above 5A Lower-voltage or lower-current supplies can be used, but available output power will be reduced. Insufficient supply current can cause voltage drop, abnormal operation or poor sound quality. If the amplifier is operated near maximum volume, an inadequate power supply may result in distortion. The power supply should have sufficient capacity for the actual amplifier load. Higher supply voltage can provide greater available output power within the module's specified operating range. 📱 Bluetooth & AUX Input The ZK-MT21 provides two audio input methods: Bluetooth Bluetooth 5.0 wireless audio input Bluetooth is the preferred input mode according to the supplied product information. Bluetooth supports automatic reconnection. Once Bluetooth is successfully connected, the module operates in Bluetooth mode. AUX Connect an external audio source through the AUX input. When using AUX, ensure the Bluetooth connection has been disconnected if necessary. 🔧 Applications DIY Bluetooth speakers 2.1 channel speaker systems Home audio projects Portable audio systems Subwoofer amplifier projects Custom speaker cabinets Desktop speaker systems Multimedia speaker systems Electronics and audio DIY projects Replacement/custom amplifier systems 🛠️ Installation & Usage Connect a suitable DC 12–24V power supply to the amplifier module. Connect the left and right speakers to their respective output terminals. Connect a suitable subwoofer to the subwoofer output. Ensure the speaker impedance is within the supported 4–8Ω range. Connect the audio source through Bluetooth or AUX. Adjust the main volume, bass, treble, subwoofer volume and frequency according to your requirements. Start with a low volume and gradually increase it. Ensure adequate ventilation and heat dissipation during high-power operation. ⚠️ Important Precautions Do not connect directly to a 24V battery pack. Use a suitable regulated DC power supply. Do not reverse the power supply polarity. Do not short-circuit the speaker outputs. Do not exceed the recommended speaker power and impedance. Ensure the power supply can provide sufficient current. Insufficient power may cause distortion or abnormal operation. Excessive load can cause the amplifier to heat up and activate thermal protection. Provide adequate ventilation during high-power operation. If distortion occurs at high volume, reduce the volume or use a more suitable power supply. The amplifier's actual output depends on the power supply, speaker impedance, audio input and overall system configuration. 📦 Package Includes 1 × ZK-MT21 Bluetooth 5.0 2.1 Channel Audio Amplifier Module
TPA3116D2 XH-M543 120W Dual Channel High Power Original Digital Power Amplifier Board
[Amplifier Board] Build your own music system with 120 watts of stereo output. TPA3116D2 XH-M548 Dual Channel 120W Digital Power Amplifier Board is newly designed digital audio amplifier board with fine quality is practical to install and use also has good performance. It features high-efficiency class D audio power amplifier with the latest and original TPA3116D2 core technology the BTL bridge circuit is more efficient than before. This product uses the double power supply transformer with a dynamic power supply range from 12V to 24V with high efficiency small quiescent current. Additionally, it is equipped with Perfect protection functions like overvoltage protection and output current limit. Features: A strong TPA3116D2 chip is a digital power amplifier chip, with low idle loss characteristics, makes it work well and quickly. Onboard, front-facing IC to improve the input sensitivity, high-definition sound quality. It can be used for car vehicle computer speaker, family audio and video, and empty square. This product has the characteristics of loud sound, the capacitance is large, excellent sound quality. There is no solder joint on the back of the circuit board, the chip capacitors, and the solder board together, so there is no possibility of short circuit. Package Includes: 1 x TPA3116D2 XH-M543 120W Dual Channel High Power Digital Power Amplifier Board
XH-M312 TPA3118D2 45W*2 Digital Amplifier Board Dual Channel Audio Amplifier Board Module
[Amplifier Board] Description XH-M312 TPA3118D2 Dual-Channel Digital Amplifier Board – 45W Output Upgrade your audio experience with the XH-M312 Digital Amplifier Board, powered by the advanced TPA3118D2 digital amplifier chip. This high-performance board delivers 45W output per channel, offering exceptional audio clarity and power. Designed for hobbyists and audio enthusiasts, it features user-friendly terminal blocks, making it a perfect ready-to-use solution for your electronic projects. Key Features: Powerful Dual-Channel Output: Delivers 45W per channel, perfect for driving a pair of 30W double speakers. Advanced Protection Mechanisms: Built with a brand-new C chip that includes: Over-voltage protection Over-current protection Over-heat protection Short-circuit protection This ensures reliable performance and longevity, even during demanding operations. Easy Connectivity: Equipped with 2P audio output terminals with a 5mm pitch, allowing secure and straightforward speaker connections. Versatile Application: Ideal for DIY audio projects, home audio systems, and electronic enthusiasts seeking high-quality sound performance. Compatibility: Perfect for superior audio output, making it suitable for custom speaker setups, audio experiments, or enhancing your existing audio systems. Boost Your Audio Performance Today! Bring your projects to life with the XH-M312 TPA3118D2 Dual-Channel Digital Amplifier Board—a reliable, high-power, and easy-to-use solution for outstanding sound quality. Why Choose the XH-M312 Amplifier Board? Whether you’re a seasoned DIYer or new to electronics, this amplifier board is built for convenience and reliability. The terminal block design simplifies connections, while the robust protection features safeguard your setup, ensuring worry-free operation. Package Includes: 1 x XH-M312 TPA3118D2 45W*2 Digital Amplifier Board
Out of stockTPA3116D2 Audio Dual Channel Stereo Digital Amplifier Board 80W+80W
[Amplifier Board] This is TPA3116D2 Audio Dual Channel Stereo Digital Amplifier Board 80W*2. The TPA3116D2 Audio Dual Channel Stereo Digital Amplifier Board is a popular and versatile amplifier module known for its performance and efficiency. Here are its key characteristics: Amplification: Capable of delivering 80 watts per channel (80W*2) in a dual-channel stereo configuration. Digital Amplifier: Utilizes digital amplification technology for high efficiency and reduced power dissipation compared to traditional analog amplifiers. Class-D Amplifier: Falls under Class-D amplifier topology, which offers high efficiency and low heat generation. Stereo Configuration: Provides two independent channels for left and right audio, ideal for stereo sound setups. Audio Quality: Known for delivering clear and high-quality audio output with minimal distortion. Wide Input Voltage Range: Compatible with a wide range of input voltages, providing flexibility in power supply options. Protection Features: May include built-in protection mechanisms such as overvoltage protection, overcurrent protection, and thermal shutdown to safeguard the amplifier and connected speakers. Compact Design: Usually comes in a compact module or board form factor, suitable for integration into various audio systems or DIY projects. Applications: Commonly used in audio systems, home theaters, DIY speaker projects, and other audio amplification applications. When using the TPA3116D2 amplifier board, connect appropriate power supplies, and take necessary precautions to optimize its performance and protect connected equipment from potential damage. Features: Dual-channel stereo configuration Output power of 80 watts per channel (80W*2) Utilizes digital Class-D amplifier technology High efficiency with reduced power dissipation Clear and high-quality audio output Wide input voltage range compatibility Built-in protection features for safety Compact and easily integrable design Input impedance: 1KΩ Input impedance: 4-8Ω Amplifier Board Suitable for various audio applications and DIY projects Package Includes: 1 x TPA3116D2 Audio Dual Channel Stereo Digital Amplifier Board 80W+80W
Out of stockTPA3116D2 50Wx2+100W Original IC 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
[Amplifier Board] This is TPA3116D2 IC 50Wx2+100W 2.1 Channel Amplifier Board 12V-24V. DC12-24V TPA3116D2 2.1 Channel Digital Subwoofer Power Amplifier Board adopts two high-quality TPA3116D2 digital amplifier chips. Sound quality is very good, high efficiency and amplifying power. 50W x 2+100W 2.1 channels (left/right channel and subwoofer channel), high efficiency and low-heat. Users can adjust the volume by themselves easily. It is powered by DC 12-24V, wide input voltage. You can check our others amplifier boards here. Features: Adopts two high-quality TPA3116D2 digital amplifier chips. Good sound quality, high efficient device and power amplifying feature. 50W x 2+100W 2.1 channels(left/right channel and subwoofer channel), high efficiency and low-heat. Powered by DC 12-24V, wide input voltage. User can adjust the volume by themselves easily. Applicable speaker impedance: 4-8 ohm. Just connect the power supply and loudspeaker box, enjoy pure digital music!. Specification Supply Voltage DC 12-24V Main Chip TPA3116 x 2 Channel Type 3 Channels(Left Channel, Right Channel, Subwoofer) Output Power 50W x 2 + 100W x 1 Subwoofer Output Match 4-8 ohm Audio Output Terminals Frequency Response Range 14-100KHz SNR 100dB Switching Frequency 1.2MHz PCB Board Size (LxWxH) mm 100 x 70 x 30 Weight 113g Shipping Weight 0.13 kg Shipping Dimensions 14 × 10 × 3 cm Package includes: 1 x TPA3116D2 50Wx2+100W Original IC 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
TG113 Bluetooth Speaker Circuit Board Module
[Audio Receiver] TG113 Bluetooth Speaker Circuit Board Module This simple Music player Board is actually what you need when you are looking for making a music system or your home theatre. It is a very perfect and small size music player, which all the makers and hobbyists can use to design their music player device like an iPod. his module has some built-in features like Bluetooth, FM, USB, SD-Card Slot, Aux & FM along with a very small amplifier which can only drive the speaker of earphones or a very low watt speaker of .2 watt – 5 watt. But, it’s always advisable to use a good quality amplifier with this module which can drive the speaker of your requirements as there is a lot of variation in the wattage rating of speakers available in the market so its hard to predict the speaker of your choice will work with this module or not. Features: Output: Single channel Digital Audio Output Input:- USB/SD Card Slot/Bluetooth/FM/AUX. DIY speakers and modified audio/car rare weapon Support MP3/WMA/WAV/ format music Power Source: USB & Battery Battery supply voltage: 5V Features/Specs: New and improve microchip technology Working voltage: 3.7V-5V DC Inbuilt sound sensor or mic for recording purposes Support: mp3/Bluetooth/USB/aux/FM Push buttons for easy handling Excellent sound quality Widely used in portable speakers Can drive a normal speaker directly Length: 43 mm Width: 38 mm Height: 11.5 mm Weight: 8 gm Applications: Stereo Headphones Wired stereo headsets and headphones Portable Bluetooth Stereo Speakers Datasheet: Package Includes : 1 x TG113 Bluetooth Speaker Circuit Board Module Note: Product Images are shown for illustrative purposes only and may differ from the actual product.
MH-M18 Wireless Bluetooth Audio Receiver Board Module BLT 4.2 MP3 Lossless Decode
[Audio Receiver] MH-M18 Wireless Bluetooth Audio Receiver Board Module – Bluetooth 4.2 MP3 Lossless Decoder The MH-M18 Wireless Bluetooth Audio Receiver Module is a compact, low-power Bluetooth 4.2 audio receiver designed to add wireless audio functionality to existing speakers, amplifiers, DIY audio systems and other projects. It supports stereo two-channel audio output and lossless decoding of WAV, WMA, FLAC, APE and MP3 formats. The module can operate from 3.7–5V and provides a transmission range of up to 20 meters under suitable conditions. ⭐ Key Features Bluetooth 4.2 wireless audio receiver Converts conventional speakers/amplifiers into Bluetooth-enabled audio systems Supports stereo dual-channel audio output Supports WAV/WMA/FLAC/APE/MP3 audio decoding Bluetooth automatic connection support Maximum transmission distance up to 20 meters in open/low-interference conditions Low power consumption Can be powered from a 3.7–4.2V lithium battery or 5V supply Compact PCB suitable for DIY projects Supports Bluetooth audio protocols including HFP, A2DP and AVRCP 📋 Technical Specifications Model: MH-M18 Bluetooth Version: Bluetooth 4.2 Operating Voltage: DC 3.7–5V Maximum Operating Current: Approximately 20mA Current in Deep Sleep: Approximately 3µA Transmission Distance: Up to 20 meters Sensitivity: -87dBm Operating Temperature: -40°C to +85°C Audio Output: Stereo, dual channel Supported Formats: WAV, WMA, FLAC, APE, MP3 Bluetooth Protocols: HFP V1.7, A2DP V1.2, AVRCP V1.5, AVCTP V1.2, AVDTP V1.2 Approx. Module Size: 23 × 16mm; some listings specify approximately 23 × 16.5 × 3mm depending on version. 🔧 Applications Convert old speakers into Bluetooth speakers DIY Bluetooth speaker projects DIY audio amplifiers Portable speaker projects Home audio systems Car audio Bluetooth upgrades Wireless audio receiver projects Custom audio and electronics projects 🛠️ Basic Connection VCC: Power input GND: Ground L: Left audio output R: Right audio output Connect the L/R audio outputs to an external amplifier. This module is an audio receiver/decoder and should not be treated as a high-power speaker amplifier. 💡 Bluetooth Indicator Fast flashing: Bluetooth not connected Steady light: Bluetooth connected Slow flashing: Bluetooth audio playback in some versions ⚠️ Important Notes Do not supply more than the specified operating voltage. For lithium-battery operation, use a suitable 3.7–4.2V supply. The maximum 20m transmission distance depends on obstacles, interference and the connected Bluetooth device. This is a Bluetooth audio receiver module, not a power amplifier. Audio output should be connected to a suitable amplifier input. IC Variant Note: This product may be supplied with different compatible IC variants, including MH-M18 or JL AS208PO1429-25C4. Functionality is specified as equivalent for this product, and the variant will be shipped randomly depending on stock. 📦 Package Includes 1 × MH-M18 Wireless Bluetooth Audio Receiver Board Module
Wuzhi Audio ZK-MT21 Bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
[Amplifier Board] Tip: Only when the audio input is sufficient and the power supply voltage/current is sufficient, there will be sufficient output power. The higher the power supply voltage, the greater the output power, and the smaller the speaker impedance, the greater the output power. Please make sure that the power of the adapter power supply is greater than the actual working power of the amplifier! You can check our others amplifier boards here. FAQ: 1. How to choose a power supply? The power supply with the board is very important. The ripple of the selected power supply must be small. A power supply with a large ripple will cause the bottom noise of the power amplifier board to become larger and there will be current noise. The higher the voltage, the greater the current, and the more adequate the output power. The power supply is 12V1A and can be equipped with 3-4inch speakers. If it is above 19V 5A, there is no problem with 8-10 inches, and the power supply must be highly regarded. If the voltage is too low, the amplified sound will easily cause sound distortion. If the current is too low, the speaker will pull down the voltage, which will result in abnormal operation or poor sound quality. It is recommended to use a power supply of 18V19V24V with a current above 5A. If you only have 9V12V or 1A 2A power supply, it can be used but the power is low. When the volume is selected close to the maximum, it may be distorted and affect the sound quality. 2. How to choose a speaker? Regarding speaker types: commonly used speakers are generally 4-8 ohms, which can be used. The left and right channel speakers need to be connected to full-range speakers or mid- to high-frequency speakers, and the power is between 20W-100W. The subwoofer speaker cannot be connected to an ordinary speaker, and a speaker with a subwoofer speaker must be connected with a power between 20-100. The dive frequency of the subwoofer speaker must be at least 50 Hz. If your speaker has a low power, such as between 20W-50W, it can be used. You need a lower power supply voltage to prevent the speaker from burning after amplifying the sound. For example, choose a power supply below 15V. If you are a 50W-100W speaker, don't worry about the problem of speaker burnout. You can choose a 12-24V power supply. The higher the selected voltage, the greater the sound or power that can be output. The speaker power should not exceed 100W, otherwise it will affect the sound quality. 3. Introduction to audio input mode This audio power amplifier module has two audio input methods: one is Bluetooth input, the other is AUX input, Bluetooth mode is preferred. Bluetooth can be connected in any mode. As long as the Bluetooth connection is successful, it is in Bluetooth mode, and the Bluetooth mode supports automatic connection back. When Bluetooth is not connected, AUX plug-in is in AUX mode. It should be note that when using AUX mode, you need to confirm that the Bluetooth connection of this module has been disconnected. 4. How to adjust the main volume? The MAIN—VOLUME knob adjusts the main volume. Right-handed main volume increases, left-handed main volume decreases. The main volume affects the volume of the left and right channels and the subwoofer. 5. How to adjust the left and right channel high and low sounds? The R&L CHANNEL—BASS knob controls the bass, right-turning bass enhancement, left-turning bass attenuation. When the knob is in the rightmost position, the bass is neither enhanced nor attenuated. The R&L CHANNEL—TREBLE knob controls the treble, the right-handed treble is enhanced, and the left-handed treble is attenuated. When the knob is in the middle position, the high pitch is neither enhanced nor attenuated. Note when adjusting the treble and bass: when the treble or bass is adjusted to the maximum by turning right, if the sound is distorted, the gain of the treble or bass adjustment is too large. You need to turn the treble or bass knob to the left to lower the gain or turn the right Turn the MAIN-VOLUME knob to the left to reduce the total volume. 6. How to adjust the subwoofer? SUBWOOFER—VOLUME knob is used to control the volume of the subwoofer. Right-handed volume increases, and left-handed volume decreases. The SUBWOOFER—FREQ knob controls the cutoff frequency of the subwoofer. The right-hand frequency increases, and the left-hand frequency decreases. The frequency adjustment range is 20HZ-200HZ. 7. The voice is small and okay. When the voice becomes louder, the voice becomes muddy? The sound is distorted, please turn down the total volume or change to a higher voltage adapter power supply. 8. The sound is small, but when the sound becomes louder, the sound freezes? If the input power is insufficient, the power supply itself is protected against intermittent power failure. Please replace it with a higher-power power supply; or if the power is too large, the power amplifier board will generate serious heat and thermal protection has occurred. Reduce power usage or enhance heat dissipation. 9. What factors are related to the sound quality? The sound quality is not only related to the power amplifier module, but also related to the power supply, sound source, and the entire audio system. Basically, every aspect of the audio system will affect the sound quality, among which the main links are the audio transmission line, the audio power supply, the tone circuit, the power amplifier circuit, the speakers and the surrounding environment. The sound quality is the best only when the sound source, power supply, amplifier module and speakers are matched. Feature: Product Name: 2.1 channel audio amplifier module Product Model: ZK-MT21 Bluetooth Version: 5.0 (no shielding, 15 meters) Input Sensitivity: 500mV Audio Input: AUX + Bluetooth Channel: 2.1 Chip Solution: Domestic power amplifier chip Power Range: DC 12-20 V / 5A above (Do not connect to 24V battery pack) Adapter Speaker: 20-100 W, 4-8 Ω Output Power: Left and right channels <50W, Subwoofer <100W Protection Mechanism: Anti reverse connection. Overheat. Overcurrent. Short circuit Product Dimensions: 93mm*90mm*22mm Package Weight : about 185g (packaging) Package Includes: 1 x ZK-MT21 bluetooth 5.0 Subwoofer Amplifier Board 50WX2+100W 2.1 Channel Power Audio Stereo Amplifier Tone Board Bass AMP AUX
Stepper Motor(28YBJ-48) with SMD ULN2003 Driver Board
[Servo Motor] The 28BYJ-48 Stepper Motor with ULN2003 Driver Board is a compact, reliable, and low-cost 5V geared stepper motor kit designed for Arduino, robotics, automation, and embedded control applications. This motor features a 4-phase, 5-wire configuration with an integrated reduction gearbox, delivering high torque and precise positioning at low speeds. One of the biggest advantages of a stepper motor is its ability to operate accurately in an open-loop control system, eliminating the need for expensive feedback sensors or encoders. The motor position is precisely controlled by simply counting the input step pulses. The included ULN2003 driver board acts as a signal amplifier, allowing low-power control signals from microcontrollers such as Arduino, Raspberry Pi, ESP32, and 8051 to safely drive the stepper motor. The driver board also features four LED indicators (A, B, C, D) that display the working status of each phase in real time, making testing and debugging easy. With its compact size, plug-and-play connector, stable operation, and high reliability, this stepper motor kit is ideal for robot arms, CNC projects, camera sliders, 3D mechanisms, automation systems, and educational electronics projects. ⭐ KEY FEATURES ✔ 28BYJ-48 Mini Geared Stepper Motor – 5V DC✔ 4-Phase, 5-Wire Configuration✔ Includes ULN2003 Stepper Motor Driver Board✔ Open-Loop Precise Control – No encoder required✔ Built-in Gear Reduction for Higher Torque✔ Plug-and-Play Interface – Easy connection✔ Phase LED Indicators on driver board✔ Compact size, lightweight & reliable✔ Perfect for Arduino, robotics & automation projects 🔧 TECHNICAL SPECIFICATIONS Stepper Motor Model: 28BYJ-48 Supply Voltage: 5V DC (commonly used version) Number of Phases: 4 Wires: 5 Stride Angle: 5.625° × 1/64 (with gearbox) Gear Reduction Ratio: 1:64 (approx.) Dimensions: 44 × 44 × 28 mm (L × B × H) Type: Geared Stepper Motor Driver Board Driver Model: ULN2003 Input Interface: Standard 5-pin connector Indicators: 4 Phase LED status indicators Function: Signal amplification & motor driving 🎯 APPLICATIONS Arduino & microcontroller projects Robotics & automation systems Camera sliders & pan-tilt systems CNC & 3D motion mechanisms Educational electronics kits Smart home & IoT projects 📦 PACKAGE INCLUDES 1 × 28BYJ-48 5V Stepper Motor 1 × ULN2003 Stepper Motor Driver Board
Bluetooth MP3 Decoding Board Module with inbuilt SD Card Slot / USB / FM / and Remote Control
[Audio, Audio Receiver] Bluetooth MP3 Decoder Board Module with USB, SD Card, FM Radio, AUX & Remote Control The Bluetooth MP3 Decoder Board Module is a compact and versatile multimedia audio player designed to add multiple audio playback options to DIY speakers, amplifier systems, home theaters, car audio systems, portable speakers, and custom audio projects. It combines Bluetooth, USB, SD/TF card, AUX input, and FM radio functions in a single convenient module. The module can be connected to a compatible audio amplifier board to create a complete multimedia audio system. It features a clear LCD display for displaying playback information, input mode, track details, and FM frequency. An included IR remote control allows convenient wireless operation from a distance. With support for popular audio formats including MP3, WMA, WAV, FLAC, and APE, the module provides flexible playback options for different music sources. ⭐ Key Features Bluetooth wireless audio receiver Built-in USB port for music playback Built-in SD/TF card slot FM radio function AUX audio input Supports USB / SD / Bluetooth / FM / AUX source selection Stereo digital audio output LCD display for playback information Includes IR remote control Supports folder selection and organized playback Supports Bluetooth stereo audio Hands-free calling support as specified Compact design for easy installation Suitable for DIY audio projects 📋 Technical Specifications Product Type: Bluetooth MP3 Decoder Board Bluetooth: Bluetooth Audio Receiver Audio Output: Stereo Digital Audio Output Input Sources: Bluetooth / USB / SD (TF) Card / AUX / FM USB Support: Yes SD/TF Card Slot: Yes FM Radio: Yes AUX Input: Yes Display: Seven segment Display Remote Control: IR Remote Included Audio Formats: MP3 / WMA / WAV / FLAC / APE Bluetooth Function: Wireless Audio Playback / Hands-Free Calling Playback Function: Folder Selection & Music Playback Installation: Audio Amplifier / DIY Speaker System Application: DIY Speakers, Home Theater, Car Audio, Portable Audio Systems Mounting Type: Panel / Enclosure Mount Power Supply: Refer to the specific module version before connection Output Connection: Connect to a compatible amplifier input Module Type: Multi-Function Audio Decoder Board 🔧 Applications DIY Bluetooth Speakers Portable Speaker Systems Home Theater Upgrades Car Audio Modification Amplifier Projects Multimedia Speaker Repair Custom Audio Systems DIY Music Players Portable Audio Systems Electronic Audio Projects 🛠️ How It Works The module works as a multi-function audio source and decoder. Select Bluetooth, USB, SD/TF card, AUX, or FM radio as the required audio source. The module decodes the selected audio signal and provides a stereo audio output that can be connected to a compatible amplifier board. For a DIY speaker project, connect the decoder module to a suitable amplifier and then connect the amplifier to the speakers. The included IR remote can be used to control playback, mode selection, track selection, volume, and other supported functions. 🔌 Installation Connect the module to a compatible power supply according to the specifications of the particular module version. Connect the audio output to the input of a suitable amplifier board and connect the amplifier output to the speakers. Insert a compatible USB drive or SD/TF card containing supported audio files, or pair the module with a Bluetooth device. AUX input and FM radio can also be selected using the module controls or remote control. 📦 Package Includes 1 × Bluetooth MP3 Decoder Board Module with USB / SD / FM / AUX 1 × IR Remote Control 1 × Power & Signal Connecting Cable ⚠️ Precautions This module is not recommended for beginners without basic electronics knowledge. Check the module's required supply voltage and polarity before powering it. Ensure all wiring is correct before switching on the power. Connect the audio output to a compatible amplifier input. Do not connect speakers directly to the decoder output unless confirmed by the specific module version. Avoid short circuits between power and signal connections. Do not expose the board to water or excessive moisture. We are not responsible for damage caused by incorrect wiring, improper installation, or misuse.
BC547 NPN Good Quality General Purpose Transistor Rapid Make
[Transistor] BC547 NPN General Purpose Transistor TO-92 Package NPN transistor in a TO-92; SOT54 plastic package. PNP complements: BC556 and BC557. This device is designed for switching and amplifier applications.BC547 is a semiconductor device used to amplify or switch electronic signals and electrical power. It is composed of semiconductor material usually with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor’s terminals controls the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits. APPLICATIONS: General-purpose switching and amplification Features/Specs: Part No: C-TBC547B Brand: CDIL Transistor Polarity: NPN Collector-Base Voltage: 50VDC Collector-Emitter Voltage: 45VDC Emitter-Base Voltage: 6VDC Continuous Collector Current: 100mA Output Capacitance: 4.5pF Transition Frequency: 300MHz DC Current Gain: 110-800 Operating Temperature Range: -55 – 150°C Power Dissipation: 625mW Low error voltage Fast switching speed Full-voltage operation High power and current handling capability Package: TO-92 Material: Plastic Package
XH-M139 50Wx2+100W 2.1 Channel Digital Subwoofer Amplifier Board 12V-24V
[Amplifier Board] DC12-24V 2.1 Channel Digital Subwoofer Power Amplifier Board adopts two high-quality digital amplifier chips. Sound quality is very good, high efficiency and amplifying power. 50W x 2+100W 2.1 channels (left/right channel and subwoofer channel), high efficiency and low-heat. Users can adjust the volume by themselves easily. It is powered by DC 12-24V, wide input voltage. Features: Adopts two high-quality digital amplifier chips. Good sound quality, high efficient device and power amplifying feature. 50W x 2+100W 2.1 channels(left/right channel and subwoofer channel), high efficiency and low-heat. Powered by DC 12-24V, wide input voltage. User can adjust the volume by themselves easily. Applicable speaker impedance: 4-8 ohm. Just connect the power supply and loudspeaker box, enjoy pure digital music!. Specification Supply Voltage DC 12-24V Main Chip CS3835E0x 2 Channel Type 3 Channels(Left Channel, Right Channel, Subwoofer) Output Power 50W x 2 + 100W x 1 Subwoofer Output Match 4-8 ohm Audio Output Terminals Frequency Response Range 14-100KHz SNR 100dB Switching Frequency 1.2MHz PCB Board Size (LxWxH) mm 100 x 70 x 30 Weight 113g Shipping Weight 0.13 kg Shipping Dimensions 14 × 10 × 3 cm Package includes: 1 x DC12-24V 2.1 Channel Digital Subwoofer Power Amplifier Board