5520A
Service Manual
6-36
Refer to Figure 6-6 for proper setup connections. Set the Calibrator Mainframe to SCOPE
mode, with the Edge menu on the display. Press O on the Calibrator Mainframe to
activate the output. Then follow these steps to verify Edge frequency.
1. Set the PM 6680’s FUNCTION to measure frequency on channel A with auto trigger,
measurement time set to 1 second or longer, 50 Ω impedance, and filter off.
2. Using the BNC cable, connect the SCOPE connector on the Calibrator Mainframe to
PM 6680 channel A.
3. Program the Calibrator Mainframe to output 2.5 V at each frequency listed in Table
6-25.
4. Allow the PM 6680 reading to stabilize, then record the PM 6680 reading for each
frequency listed in Table 6-25. Compare to the tolerance column of Table 6-25.
Table 6-25. Edge Frequency Verification
Calibrator Mainframe
Frequency
(output @ 2.5 V p-p)
PM 6680 Reading (Frequency) Tolerance
1 kHz 0.0025 Hz
10 kHz 0.025 Hz
100 kHz 0.25 Hz
1 MHz 2.5 Hz
10 MHz 25 Hz
6-53. Edge Duty Cycle Verification
This procedure uses the following equipment:
• PM 6680 Frequency Counter
• BNC cable supplied with the SC600
Refer to Figure 6-6 for proper setup connections. Set the Calibrator Mainframe to SCOPE
mode, with the Edge menu on the display. Press O on the Calibrator Mainframe to
activate the output. Then follow these steps to verify Edge duty cycle.
1. Set the PM 6680’s FUNCTION to measure duty cycle on channel A with auto
trigger, measurement time set to 1 second or longer, 50 Ω impedance, and filter off.
2. Using the BNC cable, connect the SCOPE connector on the Calibrator Mainframe to
PM 6680 channel A.
3. Program the Calibrator Mainframe to output 2.5 V at 1 MHz.
4. Allow the PM 6680 reading to stabilize. Compare the duty cycle reading to 50% ±
5%.
6-54. Edge Rise Time Verification
This procedure tests the edge function’s rise time. Aberrations are also checked with the
Tektronix 11801 oscilloscope and SD-22/26 sampling head.
The following equipment is used to verify the edge rise time.
• High Frequency Digital Storage Oscilloscope: Tektronix 11801 with Tektronix SD-
22/26 sampling head