In this article we talk about a few simple yet accurate transistor tester circuits which can used to identify whether a transistor is good or bad. Note: Please test *only* BJTs and MOSFETs (enhancement or depletion) with these circuits. Simple Good/Bad Transistor Checker using a Single LED Do you have a lot of strange old transistors […]
Tester
Simple Soil Moisture Tester Circuit with a Single IC 741
A very simple mud or soil moisture tester circuit can be built by using a single opamp and a few passive components, I have explained the details through the following article. Circuit Objective After water and sunlight the earth or the soil is the next most important natural gift that this planet has provided us […]
Simple Transistor Diode Tester Meter Circuit
In this post I have explained how to make a simple yet efficient transistor/diode tester circuit, that will not only test the quality of a BJT, but will also help to identify whether it is is an NPN or a PNP. The circuit was designed and contributed by Mr. Henry Bowman. Circuit Operation Referring to […]
Simple MOSFET Tester and Sorter Circuit
This simple MOSFET tester does a quick job of testing both enhanced mode type N and P-channel mosfets. It checks for shorts between gate, drain and source. Designed By: Henry Bowman It also distinguishes between N and P-channel mosfets. Once the connections are correctly made to the mosfet, all testing is done without reversing connections. […]
Circuit Tester Probe – PCB Fault-Finder
This simple circuit tester probe can be used for detecting short circuits, abnormal resistance conditions, continuity breaks etc inside an assembled circuit board or a PCB. The indication will be through an audible buzzer sound or an LED illumination. The described designs are all extremely safe to use even with PCBs that may have highly […]
Remote Control Infrared Tester Circuit
We all use remote control handsets for controlling various household devices such as TV, AC, Music systems, curtains etc, and sometimes we seem to have problems with these devices, or even a newly purchased remote controller unit occasionally seem to malfunction, and identifying the issue becomes quite difficult for us. This simple 2 transistor infrared […]