Tools and measuring circuit diagrams

Signal Tracer and Injector

A simple test circuit to fault find audio and radio equipment. Can be used to inject a square wave signal, rich in harmonics, or used with headphones as an audio tracer.

Zener Diode Tester

I have teamed up with Magazine Mikro Elektronica for this project. Please visit their site. I am very grateful to Aleksandar Dakic for the kind translation into Serbian and Romanian languages.

AC Current Monitor

Senses high current-flow into power cables No wire-cutting, three versions available

LM317 Regulator Tester

This is both a useful and very handy test circuit for quickly diagnosing faulty regulator IC's. In addition, Abu has a novel and innovative solution to quickly connect all 3 regulator pins - just by using an 8 pin DIL socket.

Flashing-LED Battery-status Indicator

Signals when an on-circuit battery is exhausted. 5V to 12V operating voltage.

Battery Status Indicator

There are many circuits available on the net, for indicating battery status.

Cheap Transistor 'Beta' Meter

Measures the hfe of NPN and PNP transistors. Requires a digital or analog Multimeter.

Connection Tester

A low resistance ( 0.25 - 4 ohm) continuity tester for checking soldered joints and connections.

Static Detector Negative Ion Detector

A sensitive detector for static electricity based around a single Field Effect Transistor It can also be used to detect the presence of negative ions, or test a negative ion generator.

Infra Red Remote Control Tester

A simple IR receiver to facilitate in testing of Infra Red Remote Control handsets.