9. Impulse Bandwidth Adjustments

9.Impulse Bandwidth Adjustments

Reference IF-Display Section

A4A9 IF Control

Related Performance Impulse Bandwidth Accuracy Test

Test

Description The CAL OUTPUT signal is connected to the SIGNAL INPUT 1. Each of the adjustable resolution bandwidths is selected and adjusted for the proper impulse bandwidth.

Equipment No test equipment is required for this adjustment.

Procedure 1. Position the instrument upright and remove the top cover.

2.Set the LINE switch to On, press [INSTR PRESET), and select

SIGNAL INPUT 1.

3.Connect CAL OUTPUT to SIGNAL INPUT 1.

4.Key in (CENTER FREQUENCY) 100 MHz, [FREQUENCY SPAN] 5 MHz

Cm) 3 MHz, and m.

5.Press [REFERENCE LEVEL) and adjust the DATA knob to place the signal peak near the top CRT graticule. The signal should be centered about the center line on the graticule.

6.Press [PEAK SEARCH), MKR 4 (%J, and MARKER @.

7.Using the DATA knob, adjust the marker down one side of the display signal to the 7.3 dB point; CRT MKR A annotation indicates 0.430 X

8.Adjust A4A9R60 3 MHz for MKR In] indication of 1.5 MHz while maintaining the marker at 0.430 X using the DATA knob. Refer to Figure 4-8 for the adjustment location.

9.Press MARKER In]. Adjust the marker to the 7.3 dB point on the opposite side of the signal (CRT MKR A annotation indicates 1.00 X. There are now two markers; one on each side of the signal at the 7.3 dB point.

10.CRT MKR A annotation now indicates the impulse bandwidth of the 3 MHz bandwidth. Impulse bandwidth should be 3.00 MHz 50.60 MHz

11.Key in [RESBW) 1 MHz, [FREQUENCY SPAN) 2 MHz, [PEAK SEARCH),

and CMKR). If necessary, readjust by pressing

[REFERENCE LEVEL) and using the DATA knob to place the signal peak near the top of the graticule.

12.Press MARKER IOFF) then MARKER [al.

Option 462 4-27