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Best Choice eMagTech 
eMagTech 50PCS PC817 Optocoupler in-Line 2.54mm Pitch 4-pin DIP-4 Mounting Transistor Output Opticalcoupler for Computer Feature : Integrated circuits have the advantages of small size, light weight, small solder joints, long life, high reliEMSea 
EMSea 50x Op Amp Timer Darlington Optocoupler Low Input IC Assortment Kit 10 Type Package includes: In total 50pcs 10 size, each size per 5pcs. You will get LM324, LM358, LM386, LM393, UA741, NE5532, NEBest Value SING F LTD 
SING F LTD 4X 1-Channel PC817 Optocoupler Isolation Module (3-5V) Suitable for Photoelectric Isolator Signal Ssolation 1-Channel PC817 Optocoupler Isolation module adopts 5.0 pitch screw terminals for easy wiring.Senzooe 
2PCS PC817 2 4 8 Channel Optocoupler Insulated Circuit Board Voltage Converter Adapter Module 3.6-30V Driver Light Insul 2PCS PC817 2 4 8 Channel Optocoupler Insulated Circuit Board Voltage Converter Adapter Module 3.6-30V Driver Light InsulKHADBXCP 
5PCS PC817 4 Channel Optocoupler Insulated Circuit Voltage Converter 3.6-30V Driver Light Insulation Shield 5PCS PC817 4 Channel Optocoupler Insulated Circuit Board Voltage Converter Adapter Module 3.6-30V Driver Light InsulatioSING F LTD SING F LTD 4X 1-Channel PC817 Optocoupler Isolation Module (12V) Suitable for Photoelectric Isolator Signal Ssolation an 1-Channel PC817 Optocoupler Isolation module adopts 5.0 pitch screw terminals for easy wiring.Senzooe 
2PCS PC817 2 4 8 Channel Optocoupler Insulated Circuit Board Voltage Converter Adapter Module 3.6-30V Driver Light Insul 2PCS PC817 2 4 8 Channel Optocoupler Insulated Circuit Board Voltage Converter Adapter Module 3.6-30V Driver Light InsulECSiNG ECSiNG 2Pcs 1 Channel 12V Relay Module with Optocoupler Isolation Expanding Board Support Low-Level Trigger Or High-Leve Our relays have a fault-tolerant design, even if the control line is broken, the relay will not operate, making it saferYINETTECH YINETTECH 4Pcs VTL5C3 Opto-Coupler VTL5C DIP-4 Audio Opto-Coupler (Vactrols) Linear Opto-Isolator Suitable for Many Guit Applications: Commonly used in tremolo and vibrato circuits within guitar pedals and amplifiers to create distinctive moReland Sun 5PCS 5V 9V 12V 24V 1 Channel Relay Module with Optocoupler Isolation Support High or Low Level Trigger (5V) 5PCS 5V 9V 12V 24V 1 Channel Relay Module with Optocoupler Isolation Support High or Low Level TriggerFafeicy Fafeicy Relay Module Board 1 Channel Relay Module High & Low Actuator Optocoupler for Home (5V) Fault-Tolerant Design: Fault-tolerant design,even if the control line breaks,the relay will not move.cizihuu 1pcs PC817 Optocoupler Isolation Board Voltage Converter Adapter Module,8 Way Jumper Cap Can Achieve Output Port Is High POtential Or Pull Down OutputDIANN DIANN 10pcs DC 5V Relay Module 1 Channel Relay Board with Optocoupler Support High/Low Level Trigger Relay Board Maximum Load: AC 250V/10A; DC 30V/10A With Power and Relay Action Indicator;Trigger Current: 5mAReland Sun 5PCS 5V 9V 12V 24V 1 Channel Relay Module with Optocoupler Isolation Support High or Low Level Trigger (24V) 5PCS 5V 9V 12V 24V 1 Channel Relay Module with Optocoupler Isolation Support High or Low Level TriggerEC Buying EC Buying 5Pcs 3-5V Optocoupler Isolation Board Optoelectronic Isolator EL817 PC817 Card Rail Bracket Input 3-5 V Optoco 1-way optocoupler isolation module with EL817 features, providing input voltage of DC 3V ~ 5V and output voltage suitablDIANN DIANN 10pcs DC 12V Relay Module 1 Channel Relay Board with Optocoupler Support High/Low Level Trigger Relay Board Maximum Load: AC 250V/10A; DC 30V/10A With Power and Relay Action Indicator;Trigger Current: 5mACreate idea Create idea 5pcs 817 2-Channel Optocoupler Isolation Voltage Control Switching Module 3.6-24V Driver Photoelectric Isola This module is used when it is necessary to isolate the control in actual work and voltage conversion.It can realize 3.3Reland Sun 5pcs 5V 12V 24V 2 Channel DC Relay Module with Optocoupler High/Low Level Trigger Expansion Board (24V) 5pcs 5V 12V 24V 2 Channel DC Relay Module with Optocoupler High/Low Level Trigger Expansion BoardMadifei AU 5Pcs 12V 8 Channel Relay Module Interface Board with Optocoupler 5Pcs 12V 8 Channel Relay Module Interface Board with OptocouplerCHENBO 4 pcs DC 5V 1 Channel Relay Module Board Shield High/Low Level Trigger with Optocoupler for Arduino The module uses genuine quality relay, normally open interfacesReland Sun Reland Sun 10pcs 4N38 4N37 4N36 4N35 4N33 4N32 4N27 4N28 4N25 4N26 DIP-6 IC Optocoupler (4N35) 10pcs 4N38 4N37 4N36 4N35 4N33 4N32 4N27 4N28 4N25 4N26 DIP-6 IC Optocouplercizihuu 1pcs PC817 Optocoupler Isolation Board Voltage Converter Adapter Module,4 Way Jumper Cap Can Achieve Output Port Is High POtential Or Pull Down Outputcizihuu 1pcs PC817 Optocoupler Isolation Board Voltage Converter Adapter Module,2 Way Jumper Cap Can Achieve Output Port Is High POtential Or Pull Down OutputYIQFOCA 5 Set 3V 1 Channel Relay Power Switch Board, High Level Driver Optocoupler Module Isolated Drive Control Board for ESP82 You will recevie 5Pcs 3v Relay 1 Channel power switch module compatible with 10A 250VAC and 10A 30VDC load.5pcs * 2.5 mmNikovoke 2Pcs 3V Relay Module Switch Board, 1 Channel Optocoupler Module with Isolation Control, Compatible for IoT ESP8266 and A [Rapid Response Time] This 3V Relay Module Switch Board features an ultra-fast response speed of less than 20 milliseconPhipps Electronics 5v 1 Channel Low Level Relay Module with Optocoupler 5V 1 Channel Low Level Relay Module with OptocouplerJimcat star 2PCS DC 3.3V 5V NPN Low Level Output 8-Channel Optocoupler Isolation Board Signal Converter Opto Voltage Isolation Modul 2PCS DC 3.3V 5V NPN Low level output 8-Channel Optocoupler Isolation Board Signal Converter Opto Voltage Isolation ModulHOBBYIN HOBBYIN 5PCS 1 Channel Optocoupler Isolation Module,DC12V Optocoupler Isolation Module EL817 Opto PNP NPN Signal Convert Reliable Optocoupler Isolation: The 5 PCS Optocoupler Isolation Board is designed to provide reliable signal isolation aCHENBO 2 pcs 5V 2 Channel DC 5V Relay Module with Optocoupler High/Low Level Trigger Expansion Board for Arduino Maximum load: AC 250V/10A, DC30V/10AOiyagai Oiyagai 5pcs LM393 Chip Motor Measuring Comparator Speed Sensor Module Slot Type IR Optocoupler for MCU Arduino Product Name : Speed Sensor Module;Working Voltage : DC 3.3-5VOiyagai Oiyagai 5pcs LM393 Chip Motor Measuring Comparator Speed Sensor Module Slot Type IR Optocoupler for MCU Arduino Product Name : Speed Sensor Module;Working Voltage : DC 3.3-5VZopsc Zopsc 4 Channel Voltage Converter Optocoupler Isolated Board Adapter Module, 3.3V/5V to 3.6V/24V, Strong Anti-Interferen 【Easy for Use】It can realize 3.3V or 5V to control the interface of 3.6--24V voltage level. After the control terminal iGeneric 4 Channel DC 12V Relay Module with Optocoupler Isolation Relay Control Board Maximum 250V 10A and DC30V 10A.Reland Sun Reland Sun 10pcs 4N38 4N37 4N36 4N35 4N33 4N32 4N27 4N28 4N25 4N26 DIP-6 IC Optocoupler (4N26) 10pcs 4N38 4N37 4N36 4N35 4N33 4N32 4N27 4N28 4N25 4N26 DIP-6 IC OptocouplerDIANN DIANN 2pcs 4 Channel 12V Relay Module with Optocoupler High or Low Level Trigger Expansion Board Relay Module : Channel: 4 Channel; Working Voltage: DC 12V; Equipped with High-Current Relay, Maximum Load: AC250V 10A,Reland Sun 3.3V 5V 12V 3 Channel Relay Module 5mA With Optocoupler Isolation Signal (3.3V-5V) 3.3V 5V 12V 3 Channel Relay Module 5mA With Optocoupler Isolation SignalGikfun Gikfun OPTOCOUPLER DIP-4 PC817C PC817 for Arduino Diy (Pack of 20pcs) AE1143 Gikfun Packing 20pcs OPTOCOUPLER DIP-4 PC817C PC817ELEGOO ELEGOO 4 Channel DC 5V Relay Module with Optocoupler for Arduino UNO R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 This relay module is 5V active low. Relay output maximum contact is AC250V 10A and DC30V 10A.Sitojart Star 10Pcs 12V 1-Channel PC817 Optocoupler Isolator 10Pcs 12V 1-Channel PC817 Optocoupler IsolatorASHATA Relay Module,8 Channel Optocoupler Relay Module Board High & Low Trigger 5V/12V/24V,Relay Module with Isolated Optocoupl Adopt patch photocoupler isolation, strong driving ability, stable performance. Trigger current is 5mA.Reland Sun Reland Sun NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectio NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectional TransmiPhipps Electronics 5v 2 Channel Relay Module with Optocoupler 5V 2 Channel Relay Module with OptocouplerReland Sun Reland Sun NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectio NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectional TransmiLystin Lystin 8 Channel DC 5V Relay Module Board with Optocoupler for Arduino UNO R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspb DC 5V 8-Channel Relay interface board, each one needs 15-20mA Driver Current.Reland Sun IR Infrared Slotted Optical Speed Measuring Sensor Detection Optocoupler Module for Motor Test Reland SunGeneric DC 12V Relay Module 2-Channel Relay Switch with Optocoupler Isolation High/Low Level Trigger Fault-tolerant design, even if the control line is broken, the relay will not move.NOYITO NOYITO PC817 4-Channel Optocoupler Isolation Board Voltage Converter Adapter Module 3.6-30V Driver Photoelectric Isolate Shanrya AC Optocoupler Module, Optocoupler Module 3P Terminal Connected to The Microcontroller Input for Workshop for Laboratory Output TTL level, can be detected with the microcontroller. The power supply can be 3‑5V.Reland Sun 5V 12V 24V 8 Channel Relay Module Interface Board for 51/AVR/AVR/ARM with Optocoupler Protection (12V) 5V 12V 24V 8 Channel Relay Module Interface Board for 51/AVR/AVR/ARM with Optocoupler ProtectionELEGOO ELEGOO 8 Channel DC 5V Relay Module with Optocoupler for Arduino UNO R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 5V 8-Channel Relay interface board, each one needs about 70mA Driver Current; Equiped with high-current relay, AC250V 10Reland Sun 5V 9V 12V 24V 1 Channel Relay Module with Optocoupler Isolation Support High or Low Level Trigger (9V) Module uses genuine high quality relay, normally open interface maximum load: AC 250V / 10A, DC 30V / 10AKiBcsLic KiBcsLic Small Optocoupler Detection Device with Indicator Light, 3rd, 4th and 5th. 【Compatibility】: Clearly marked pin 1 (with a small dot) on both the optocoupler and test board for accurate alignment d1PZ 1PZ DCR-M70 DC 5V 8 Channel Relay Module Board Solid State Relay with Optocoupler Replacement for Arduino UNO R3 MEGA 25 【Compatibility】 Suitable for all kinds of electronic devicesASHATA Relay Module,8 Channel Optocoupler Relay Module Board High & Low Trigger 5V/12V/24V,Relay Module with Isolated Optocoupl Adopt patch photocoupler isolation, strong driving ability, stable performance. Trigger current is 5mA.EUIOOVM EUIOOVM 24V Optocoupler Isolation Board with Long Wire Button Connection Signal Level Conversion Works Easily with 2K Hz A mini optocoupler isolation,signal level conversion moduleKAIYUEMAOYI KAIYUEMAOYI Optocoupler Test, Mini USB Or Type-C Power Supply, Easy to Use, 3rd, 4th and 5th Generation 【Easy Use】: Connect the optocoupler test board to a USB or Type C power source, then use the to the optocoupler; a flashGeneric Mini Optocoupler Isolation Module Signal Level Conversion with Signal Input Indicator Light Size 4 X 25mm Optocoupler Is A mini optocoupler isolation,signal level conversion moduleGeneric Versatile Optocoupler Isolation Module Well Suited for 24V Systems Signal Level Conversion Made Easy Mini Optocoupler Is A mini optocoupler isolation,signal level conversion moduleMotiveTech MotiveTech Optocoupler Test Instrument Electronic Repair Sturdy Online Detector 3rd 4TH 5TH Gen 【Reliability】: Maintain good between the test board and optocoupler during measurement for accurate resultsCHICIRIS CHICIRIS One Way Relay Module, 30A High Power Optocoupler Isolation Relay Module for Stable Performance in Industrial Us [SUPERIOR OPTOCOUPLER QUALITY] Crafted with top-notch miniature optocoupler for stable and reliable performance.Generic Signal Level Convert Optocoupler Isolation Board Designed for Seamless Integration in 24V Circuits Size7.4 X 25mm/0.3 X A mini optocoupler isolation,signal level conversion moduleASHATA Relay Module,8 Channel Optocoupler Relay Module Board High & Low Trigger 5V/12V/24V,Relay Module with Isolated Optocoupl Adopt patch photocoupler isolation, strong driving ability, stable performance. Trigger current is 5mA.Tbest Tbest 817 4-Channel Optocoupler Isolated Voltage Converter Module for Safe Isolation Control: This 4-channel optocoupler isolated board is designed for applications requiring isolation control anGeneric Signal Converters for Optocoupler Isolation Modules Greatly Connection Ease Systems Compatible Signals Optocoupler Isola A mini optocoupler isolation,signal level conversion moduleEacam 3 Channel Relay Module, High Voltage Relay Board with Isolated Optocoupler, High Low Level Trigger, for Various Applicat [Efficient & Versatile] This high voltage relay module boasts high efficiency, sleek design, simple , and a wide range oCryfokt Cryfokt 30A High Power Two Way Relay Module with Miniature Optocoupler for Stable Performance, Black Barrier Terminal, I [CUSTOMIZABLE Actuator] Choose between high/low level Actuator options for flexible usage.JESSINIE JESSINIE 3 Channel AC 220V Optocoupler Isolation Module AC Detection Module 220V Testing Module 3 Channel 220V optocoupler isolation module, using NPN transistor to output saturated conduction current up to 100-300MAJESSINIE JESSINIE 3 Channel AC 220V Optocoupler Isolation Module AC Detection Module 220V Testing Module 3 Channel 220V optocoupler isolation module, using NPN transistor to output saturated conduction current up to 100-300MALeeQinersw LeeQinersw Optocoupler Test Online Testing Tool Small Reliability Easy Use 4 Pin PCB Repair 【Reliability】: Maintain good between the test board and optocoupler during measurement for accurate resultsReland Sun Reland Sun NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectio NPN Output Four-Way optocoupler Isolation PLC Level Voltage Conversion Board 1.8V 3.3V 5V 12V 24V Unidirectional Transmiperfk Perfk Optocoupler Detection Instrument Online Detection Tools Small Easy Install with Indicator Light 3rd 4TH 5TH Gen PC 【Material】:The Optocoupler Test Instrument is made from PC polycarbonate material, ensuring long time use and sturdyEacam 8 Channel AC Optocoupler Isolation Module Voltage Detect Board for PLC Access, Small Size Easy to Carry Green 2P 5.0 Ter [Versatile Applications] Ideal for various settings, ensuring good performance and ease of storage and transport.perfk Perfk Optocoupler Detection Instrument Online Detection Tools Small Easy Install with Indicator Light 3rd 4TH 5TH Gen PC 【Material】:The Optocoupler Test Instrument is made from PC polycarbonate material, ensuring long time use and sturdyKaifucy Kaifucy Optocoupler Tester Online Test Detection Tool for Electronic Repair Special 4 Pin Optocoupler Test PCB Repair Gr 1, test to confirm that the board under test has been powered off, and the electrolytic capacitors of the motherboard daShanrya 4 Channel Optocoupler Isolation Board, 817 Optocoupler Voltage Converter Adapter Module for Optical Isolation It can drive high voltage driving applications such as high power transistors and MOS tubes, and also directly drive lowKaifucy Kaifucy Optocoupler Tester Online Test Detection Tool for Electronic Repair Special 4 Pin Optocoupler Test PCB Repair Gr 2, confirm the optocoupler pin 1 (with a small dot on the foot test board also has the corresponding 1 feet of the logo)TYSQXQ 1pcs D207 ILD207T optocoupler SMD SOP8 Dual-Channel optocoupler Model Number: ILD207Tzozii zozii Optocoupler Tester Kit 555 Application Circuit Board Practice Welding DIY Electronic Spare Parts Kit Without DC Ca Optocouplers, also known as optocouplers, are commonly used electronic components that are difficult to test with ordinapredolo predolo Optocoupler Detection Instrument 3rd 4TH 5TH Gen Reliability Test Board USB Or 【Reliability】: Maintain good between the test board and optocoupler during measurement for accurate resultsIOIUSKKU IOIUSKKU Optocoupler Isolation Modules Mini Size 4 X 25mm Provide Effective Signal Level Conversion Effortlessly Optocou A mini optocoupler isolation,signal level conversion moduleIndependently published Electronic Components: A Beginner’s Guide To Diodes, Resistors, Capacitors, Transistors, Inductors, Integrated Circuits, Domzhili Domzhili Optocoupler Tester Online Test Detection Tool for Electronic Repair Special 4 Pin Optocoupler Test PCB Repair G 3, the optocoupler test board connected to the USB power cord, the test board probe contact need to test the optocouplerzozii zozii Optocoupler Tester Kit 555 Application Circuit Board Practice Welding DIY Electronic Spare Parts Kit with DC Cable Optocouplers, also known as optocouplers, are commonly used electronic components that are difficult to test with ordinaMarhynchus Marhynchus Optocoupler Isolation Relay Module, High Level Actuator 3 Channel Relay Module with Optocoupler Isolation, DC [Independent Control] This 3 channel relay module ensures independent control without interference, for home automationKNACRO KNACRO DC 5V 2 Channel Relay Module with optocoupler Isolation Support High Level Low Level Triggered Module using genuine quality relay, normally open interfaces Maximum load: AC 250V / 10A, DC 30V / 10A;koolsoo koolsoo Optocoupler Detection Instrument 4 Pin Professional Mini Sturdy Practical Test 【Reliability】: Maintain good between the test board and optocoupler during measurement for accurate resultsTENOL TENOL Optocoupler Test Online Testing Tool Easy Use USB or Type C Power Source Test Board Compact Reliability 4 Pin PCB 【Easy Use】: Connect the optocoupler test board to a USB or Type C power source, then use the to the optocoupler; a flashPerfeclan Perfeclan Optocoupler Detection Instrument 4 Pin Easy Install Sturdy Mini Practical Professional Online Detection Tools 【Material】:The Optocoupler Test Instrument is made from PC polycarbonate material, ensuring long time use and sturdyEigell Eigell Optocoupler Detection Instrument 3rd 4TH 5TH Gen USB Or Type C Power Source 【Compatibility】: Clearly marked pin 1 (with a small dot) on both the optocoupler and test board for accurate alignment dMetieFasia MetieFasia Online Test Tool for Optocouplers: Easy to Use, USB Or Type-C Powered, Compact and Reliable Test Board, Circu 【Easy Use】: Connect the optocoupler test board to a USB or Type C power source, then use the to the optocoupler; a flashTENOL TENOL Optocoupler Test Online Testing Tool Easy Use USB or Type C Power Source Test Board Compact Reliability 4 Pin PCB 【Easy Use】: Connect the optocoupler test board to a USB or Type C power source, then use the to the optocoupler; a flashGeneric 5PCS/LOT AQH3223 Optocoupler DIP-7 Optoisolator Optocoupler AQH3223 DIP-7 （5pieces）Gump's grocery Gump's grocery PC817 4-Channel Voltage Converter Module Optocoupler Isolation Driving Module 1.Driving Port Signal Voltage:3.6-24VKaifucy Kaifucy Optocoupler Tester Optocoupler Test Detection Tool Optocoupler Online Test Module Optocoupler Electronic Repair Before testing, the motherboard must be powered off and then discharged. Testing cannot be carried out while the power iharayaa harayaa Optocoupler Test Instrument PCB Repair USB Or Type C Power Source Sturdy Mini 【Note】: Ensure the tested board is powered off and the main electrolytic capacitor is fully discharged before testing; nKNACRO KNACRO 1 Channel Relay Module DC 24V 30A with optocoupler Isolation Support High-Level Low-Level Triggered Authentic quality module 30A relay, normally open interfaces Maximum load: AC 250V / 30A, DC 30V / 30A;Folpus Folpus Optocoupler Test Instrument Electronic Repair with Indicator Light Practical Mini 3rd 4TH 5TH Gen Online Detectio 【Material】:The Optocoupler Test Instrument is made from PC polycarbonate material, ensuring long time use and sturdyKaifucy Kaifucy 2X Optocoupler Tester Online Test Detection Tool for Electronic Repair Special 4 Pin Optocoupler Test PCB Repair 2, confirm the optocoupler pin 1 (with a small dot on the foot test board also has the corresponding 1 feet of the logo)Abbraccia Abbraccia Optocoupler Test 4 Pin Easy Install Sturdy Test Board Mini with Indicator Light Online Testing Tool Electronic 【Reliability】: Maintain good between the test board and optocoupler during measurement for accurate resultsReland Sun 5PCS/LOT IR Infrared Slotted Optical Speed Measuring Sensor Detection Optocoupler Module for Motor Test Reland Sun