Having just built your new masterpiece, it is usually with great trepidation that one applies power. There are few things quite so disheartening as seeing your creation “go up in smoke” just because of a simple mistake.
The easiest way to avoid this is to have a power supply that allows you to adjust the voltage, so you can see that everything works as it should before the main supply is connected. The lab supply shown will current limit at around 800mA (this varies a bit because of the regulators), and can supply from +/-1.2V up to about +/-25V.
Using a dual-gang pot allows both supplies to be set simultaneously to the same voltage, and you can add metering for voltage and current if you want to. These will add substantially to the cost, but can be very useful.
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