Testing germanium diodes. If you have an analog VOM, you may be surprised how high the short circuit current is on the Rx1 range. Mine runs 120mA. Note that this is sufficient current to destroy a ...

This circuit can also be used to check forward voltage drop across diodes and LEDs at a pre-setted value of current. Here the maximum test current is near 12 mA with the 2.7K ballast resistor (R3) ...

The simple Diode and LED Tester presented here costs under £5 to build ... If the diode being tested were open-circuit both LEDs on the unit would remain lit. A stable Multivibrator ...

For testing diodes, the waveform generator is configured to a ±2.5-V ramp signal at 100 Hz. This is a low-frequency test, so the high-resolution mode is used to reduce noise.

The circuit is simple enough: it uses a capacitor, a resistor, and a pair of diodes (one of them a zener diode). He uses this basic circuit to drive simple regulators with input and output filter ...