Question

Sine wave measurement:

Images 6.9 – 6.12 show a sine wave. Note that Image 6.9 is a close up of the function generator’s frequency display.

BK PRECISION ® 4011A 5MHz FUNC KHz Hz • 2 E19 GATE OFF ON FREQUENCY COARSE FINE [Image 6.9 - Function Generator Frequency Display]

Using images 6.10 – 6.12, determine the amplitude of the sine wave. Be sure to include proper units:

# of vertical divisions
VOLT/DIV
Amplitude

Determine the period and calculate the frequency:

# of horizontal divisions
TIME/DIV
Period
Frequency

Assuming that the frequency displayed in Image 6.9 is more accurate than the oscilloscope, what is the % error in frequency?

% Error

Calculate the RMS voltage for this sine wave:

Voltage (RMS)

Answer 1

Volt/Div = 0.5

Amplitude,A = 0.5 X 2.5 = 1.25 V

Time/Div = 0.1 ms

Period,T = 0.1 X 4.5 = 0.45 ms

Frequency, f = $f = \frac{1}{T} = \frac{1}{0.45 * 10^{-3}} = 2222.22 Hz$

Percent Error, $= \frac{\left | 2222.22 - 2279\right |}{2279}*100 = 2.49$

Percent Error = 2.49 %

Voltage (RMS), $V_{rms} = \frac{V}{\sqrt{2}} = \frac{1.25}{\sqrt{2}} = 0.88 V$