**Oscilloscopes**

The two controls on an oscilloscope we are interested in are;

**Y-gain**in volts/division, 1 v/div.**Time base**in time/division, e.g. 0.002 s/div.

Input connected to ground (**zero volts**) and **timebase switched off**, oscilloscope trace is a spot in the middle of the screen.

**3 volts** from a **dc** battery (**Y gain set to 1V/div, timebase off**), the oscilloscope trace is a spot which moves 3 squares (divisions) up.

Input connected to ground (**zero volts**) and **timebase switched on**, trace appears as a horizontal line in the middle of the screen.

**3 volts** from a **dc** battery (**Y gain set to 1V/div, timebase on),** trace appears as a horizontal line 3 squares above the middle.

**3 volts** from an **ac** power supply (**Y gain set to 1V/div, timebase off**), trace appears as a vertical line 6 squares long.

**3 volts** from an **ac** power supply (**Y gain set to 1V/div, timebase on 0.002 s/div**), sine like trace appears.

The **peak voltage** (amplitude) is 3V.

The** time period** (T) is 8 squares x 0.002 = 0.016 s.

We can **calculate the frequency** (f) in hertz (Hz) using the equation below;

f = 1 divided by 0.016 = 62.5 Hz