To test a diode, follow this procedure:
a. Connect the horizontal or sweep probe of the scope to the X terminal of
the tester (fig 3-14) and adjust the display to a 2-centimeter horizontal line
(common scope lead to reference).
b. Remove the X lead and connect the vertical probe of the scope to the Y
terminal of the tester (fig 3-14) and adjust the vertical display on the scope to 4
centimeters by adjusting the variable AC input to the tester.
c. Reconnect the X lead as mentioned above.
display on the scope as illustrated in Figure 3-15a.
d. Connect the diode between the diode terminals on the tester and compare
the trace on the oscilloscope with those shown in Figure 3-15.
e. Determine the condition of the diode.
By testing known good diodes you
can make your own trace patterns for comparison with other diodes.