4-14 Service Guide
Start Troubleshooting Here 8719ET/20ET/22ET
Power Supply Check 8719ES/20ES/22ES
RF Network Analyzers
Power Supply Check
Check the Rear Panel LEDs
Switch on the analyzer and look directly at the rear panel. Notice the condition of the two
LEDs on the preregulator (A15). (See Figure 4-3.)
• The upper (red) LED should be off.
• The lower (green) LED should be on.
Figure 4-3 A15 Preregulator LEDs
Check the Post Regulator (A8) LEDs
Remove the analyzer's top cover. Switch on the power. Inspect the green LEDs along the
top edge of the post-regulator (A8) assembly.
• All 9 green LEDs should be on.
• The fan should be audible.
In case of difficulty, refer to Chapter 5 , “Power Supply Troubleshooting.”