Nassau Community College
Electronics and Telecommunications
Reference Sheet

 

Oscilloscope Initial Setup

There are four sections of the oscilloscope that must be considered when initially setting up the oscilloscope for use. These include the screen controls, the triggering controls, the time base controls and the vertical amplifier controls. This reference sheet will discuss each set of controls as they pertain to setting up the oscilloscope for basic voltage or period measurements.

 

Triggering Controls:

Remember that the trigger section of the oscilloscope determines when the oscilloscope starts tracing the signal on the display. The trigger controls let you stabilize repeating waveforms.

To set up the triggering for a basic measurement:

  1. Set the SOURCE control (1 above) to INT (internal) for most signals or LINE when working with power supplies. EXT (external) triggering will not be discussed, since it is not used in basic measurements.
  2. The EXT COUPLING (2) control may be in any position and nothing should be connected to the EXT INPUT BNC connector (4).
  3. The INT (3) switch should be set to the channel whose signal is being used to trigger the trace. This is usually set to CH. 1
  4. The MODE (5) switch should be set to AUTO.
  5. The SLOPE (6) switch is usually set in the UP to the select positive slope triggering.
  6. Adjust the LEVEL control (7) until a stable trace is seen on the display. You may also have to adjust the VAR HOLDOFF (8) to stabilize the trace.

 

 

Screen Controls:

The screen controls adjust the appearance of the trace on the screen.

Setting The Screen Controls:

  1. Adjust the AUTO INTENSITY (2 above) control to yield the dimmest visible trace possible. Reducing the intensity of the trace produces a thinner line on the screen, increasing the accuracy of your measurements.
  2. Adjust the AUTO FOCUS (3) control to yield the sharpest trace possible.
  3. The BEAM FIND (4) control is used to "find" the beam when it is off the screen.

 

 

Vertical Amplifier Controls:

Remember the vertical amplifier controls the height of the trace on the screen. Itís like the zoom control on a microscope. The signal size doesnít change, only how we look at the signal. There are two channels on the 2213, allowing us to look at two signals simultaneously.

Setting The Vertical Amplifier Controls:

  1. Connect the probe to the Ch. 1 and or Ch. 2 BNC connectors (1 above ).
  2. Set the VERT MODE ADD-ALT-CHOP switch (2) to ALT.
  3. Set the VERT MODE CH1-BOTH-CH2 switch (4) to the channel which you wish to see.
  4. Set the coupling switch (5) to AC. If the DC level of a signal must be known set the switch to DC.
  5. Adjust the VOLTS/DIV control (3) for the channel you are viewing to get the largest possible trace without going off the top or bottom of the screen. You may have to adjust the POSITION control (6) to move the trace up or down as you change the VOLTS/DIV control.

 

 

Time Base Controls:

Remember the time base determines how fast the trace moves across the screen. The time base sets the value of each horizontal division.

Setting The Time Base:

  1. Set the HORIZONTAL MODE (1 above) switch to NO DLY (No Delay).
  2. Since delay is not being used, the DELAY TIME and MULTIPLIER controls (2) may be set to any position.
  3. Adjust the SEC/DIV (4) to yield one or two cycles of the signal on the screen.
  4. The POSITION (3) control may be adjusted to position the signal as desired.