T.K. Hareendran

T.K. Hareendran is an Internationally certified Professional Freelance Technical Author and Circuit Designer with more than 25 years of experience in the domain. Now he is actively engaged in the expansion of «TechNode», an advanced, independent electronics R&D lab founded & promoted by him.

Areas of interest of the author: Electronic components Automation Beginners Relay Audio History of Electronics High Voltage Supply Measurement Microcontrollers Usage Analogue Design Oscillators Tools and Technologies Robots Power Security Light Solar

Publications on RadioLocman by the author T.K. Hareendran:

Universal homing sensor: A hands-on guide for makers, engineers
Nov 13, 2025
Hybrid relay basics: Why engineers are switching smarter
Oct 6, 2025
Revisiting µPC1237, a classic audio amplifier
Sep 23, 2025
Hands-on with hobby-grade arc generator modules
Sep 9, 2025
Build automatic transfer switch (ATS) with simple analog electronics
Sep 8, 2025
A practical design guide for lightning detectors
Aug 4, 2025
How hot swap circuits and controllers work
Jun 3, 2025
Ultrasonic mist maker (DIY)
Dec 24, 2024
Handheld electric PCB drill speed controller
Sep 28, 2023
Portable Power Inverter Circuit
Jul 19, 2021
Use Inexpensive Components To Create An Infrared Close-Object Alert Circuit
Dec 10, 2018
Smart Power Supply for Microcontroller Projects
Feb 19, 2017
Low-Cost Impact Sensor Uses Piezoelectric Device
Feb 2, 2014
Outdoor Garden Solar Lights
Oct 12, 2010