HP TM 11-6625-2779-14&P manual Front Panel Trouble Analysis Contd, Front Panel Troubleshooting

Model 3555B				Section V
	Table 5-6. Front Panel Trouble Analysis (Cont'd)
		3555B SHOULD INDICATE	SET ACTUALLY	CORRECTIVE
INPUT CONDITIONS	FUNCTION	(RANGE + METER)*	INDICATES	ACTION
LEVEL -30dBm	Change RANGE to -30dBm	-30dBm ±0.2dBm		See Paragraph 5-35
LEVEL 40dBm	Change RANGE to 400dBm	-40dBm ±0.2dBm		See Paragraph 5-35,
				Table 5-9
LEVEL -500dBm	Change RANGE to -50dBm	-50dBm ±0.2dBm		See Paragraph 5-35,
				Table 5-9
LEVEL -60dBm	Change RANGE to -60dBm	-60dBm ±0.2dBm		See Paragraph 5-35,
				Table 5-9
LEVEL -70dBm	Change RANGE to -70dBm	-70dBm ±0.2dBm		See Paragraph 5-35,
				Table 5-9
LEVEL -80dBm	Change RANGE to -80dBm	-80dBm ±0.2dBm		See Paragraph 5-35,
LEVEL 0dBm	RANGE to 0dBm	0dBm		Table 5-9
	INPUT: TMS, TERM	Measure 270mV ac
		±0.2dBm at
NG CHECK		AC MON jacks		See Paragraph 5-38
75 UNBAL, Connect	RANGE: 0dBm	Adjust oscillator
UNBAL signal	FUNCTION: VF/Nm	level for 0dBm
between tip and ring	600 BAL	on 3555B meter
Change input	Depress NG button	-40dBm		Refer to Table 5-8
connection. Connect	Change RANGE to 40dBm
signal between tip
and ring and sleeve		*Some meter jitter may
(tip and ring shorted		be experienced, but the
together), ground		reading should be within
lead to sleeve		the tolerance indicated.

c.Schematics-- The schematic diagrams contain dc voltage levels and signal levels for a specified input condition. This will assist in troubleshooting individual circuits.

5-31. FRONT PANEL TROUBLESHOOTING.

5-32. Before attempting to troubleshoot the set, first determine from the front panel controls exactly which functions are performing properly and which ones are not. In this way, many troubles can be isolated to a specific area and sometimes to a component.

5-33. Table 5-6is a step by step procedure for checking out the front panel controls. This table indicates what the results should be for each check along with the specified tolerance. A space is provided to enter your results. If these spaces are completed for each check, they will be of great assistance in making

further troubleshooting checks. Whenever a discrepancy exists between your results and those

indicated in column 3, refer to the "corrective action" column.

NOTE

This table is designed to help locate catastrophic failures. If your set is only out of the specified tolerances,

a complete adjustment and calibration procedure should be performed as described in Paragraph 5-14.

5-34. FUNCTION TROUBLESHOOTING.

a.First determine from the Front Panel Analysis chart (Table 5-6)exactly which function is defective. Refer to Table 5-7for the probable cause of the malfunction in the FUNCTION switch assembly.

5-35. RANGE TROUBLESHOOTING.

5-13