Oscilloscopes

A. 1) Calculate the period, T, in seconds, of waves on an oscilloscope trace when one wavelength takes up 2 divisions on the screen and the timebase control is set at 0.1seconds per division (2 div @ 0.1 s/div).

Hint: multiply the number of divisions by the timebase setting.

2) Calculate the number of waves per second (the frequency) in Hertz using the formula f = 1 / T (with T in seconds) - show your working!

B. Repeat question A for these - show your working!

1) 2.5 div @ 0.1 s/div

2) 1.0 div @ 0.2 s/div.

3) 1.8 div @ 1ms /div (remember 1 ms = 1 millisecond = 1 thousandth of a second)

C. A pupil is working with a signal generator and needs to know the range of frequencies it can produce. The pupil connects an oscilloscope to the signal generator to try and find out what these frequencies are. Her notebook contains the following information:

Lowest Frequency: Timebase set at 0.2s/div. Period = 6.5 div.

Highest Frequency: Timebase set at 1 m s/div. Period = 7 div.

First, use these results to calculate the period in seconds - show your working!

Then calculate the frequency of the signal produced in Hertz and convert it to a suitable unit if necessary- show all your working!

D. After having found the maximum and minimum frequencies, the pupil suspects that the frequency scale on the signal generator is inaccurate. She decides to use the oscilloscope to test its accuracy and her notebook contains the following table:

Use her results to calculate the measured frequency of each row in the table, copying and completing the table as you go. How do you find the accuracy of the signal generator?

You will need to show your working separately.