Introducing: The Oscilloscope

252 Hacking Electronics

● It displays how much current is being consumed. ● You can limit the current consumption. ● You can use it in constant current mode when testing LEDs. ● You can adjust the voltage easily.

The control panel has an Output switch that turns the output voltage on and off, and two knobs that control the voltage and current.

If I am powering up some project for the first time, I will often follow this procedure:

1. Set the current to its minimum setting. 2. Set the desired voltage. 3. Turn on the output (the voltage will probably drop). 4. Increase the current and watch the voltage rise, making sure that the current isn’t rising to an unexpected level.

Introducing: The Oscilloscope

Oscilloscopes (Figure 11-8) are an indispensable tool for any kind of electronics design or test where you are looking at a signal that changes over time. They are a relatively expensive

Figure 11-7 A lab power supply

Figure 11-8 A low-cost digital oscilloscope