Triggering of an Oscilloscope

To learn basic triggering of the Tektronix 2236 oscilloscope, there are three switches that you need to know about.  These switches are located close to the bottom of the triggering section of the scope, they are labeled A & B INT, A SOURCE, and A EXT COUPLING. The A SOURCE switch is used to control where you trigger the scope from INT, LINE, or EXT.  The A EXT COUPLING switch is used to control the external trigger.

To change which channel the oscilloscope triggers off of you should use the switch labeled A & B INT.  This switch has three modes; CH1, Vert Mode, and CH2.  If the picture is not very good make sure that the A SOURCE switch is in the INT position.

The Tektronix 2236 oscilloscope has the option of using an external trigger.  To use the external trigger, you must have the A SOURCE switch in the EXT position, then you can connect a probe to the EXT INPUT connector, which is located at the bottom right of the oscilloscope.

25. A Trigger Mode Switches 26. TRIG'D-READY Indicator 27. A Trigger Level Control 28. Slope Switches 29. A Source Switch 30. A & B INT Switch 31. A EXT Coupling Switch 32. EXT Input Connector 33. B Trigger Level Control 34. VAR HOLDOFF Control