User:Brian P. Josey/Notebook/Junior Lab/2010/08/23

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Junior Lab Notes, Oscilloscope

Brian P. Josey 18:52, 23 August 2010 (EDT) loose disorganized notes for the class, will organize soon when I have a good system worked out.

Things that I've figured out (function generator):

  • Range: changes the order of magnitude that the frequency changes on
  • Duty Cycle: changes the distance between consequitive peaks in the signal
  • CMOS Level: is still a mystery
  • DC Offset: adds or subtracts a constant voltage to the whole of the signal
  • Output Level: the magnitude of the signal
  • Sweep: has two main points and two switches:
    • lin/log: changes whether it sweeps through frequencies linearly or logarithmically
    • ext/int: switches between and internal and external source
    • time: the time it takes to cycle between frequencies
    • width: the range of frequencies that it will sample through

On the oscilloscope:

  • Position knob: changes moves the signal on the screne
  • Volts/div and Sec/div: changes the scale of the graph

Setting up the cursor:

  • hit the cursor button, select what you want to measure on the first button
  • select the channel that you want
  • use the position knobs to change the location of the cursors, a light will come on to indicate that the cursors can be moved with the knobs
  • display will display the difference between the two cursors, and their individual locations
  • channel one will be cursor one, and channel two would be cursor two

Procedure

Using the procedure on the course webpage, here's a link.

Set up the frequency at 250 volts Function goes from two lines below the horizontal, to two above the horizontal, with each line representing 1 volt, giving a measured voltage of 4 volts. Using the cursors we get 3.96 volts. Using the measure function, it oscilates between 3.92 V and 3.88 V, spending equal time at both, so I measure it at 3.90 V, the mean value.

Large Amplitude

  • by grid: 5.5 grid at 5 V per line for 25 V
  • by cursor: 22.6 V delta
  • by measure: 22.8 V

Small Amplitude

  • by grid: 5.5 grid at 500 mV for 2.25V
  • by cursor: delta= 2.18V
  • by measure: 2.18 V

Large DC Offset

  • by grid: 7.75 V
  • by cursor: 7.76 V
  • by measure: 7.76V

If the graph goes off of the screen, the oscilloscope has to estimate the values.

Triggering

Insert information about triggering here.

AC Coupling

.01 μF 10 kΩ

Ideas for set writing up

Notebook bad, need to keep work and school separate so that it's easier to search through them individually. Page with headers as:

  • pre-notes/useful links
  • in lab notes/ raw data and thoughts
  • summary
  • final write up, if applicable
  • tricks and tips? for next year's group (maybe)