Torture Rack

How can you find out how stable a lab or benchtop supply is? You can get a good impression of the stability of a power supply under various conditions by loading the output dynamically. This can be implemented using just a handful of components.Apart from obvious factors such as output voltage and current, noise, hum and output resistance, it is also important that a power supply has a good regulation under varying load conditions. A standard test for this uses a resistor array across the output that can be switched between two values.