TM 11-6625-2781-14&P-2
Section VIII
Table 8-4. System Test and Troubleshooting Procedure (cont' )
d
TEST
FAULT
PROCEDURE
14.
Set LOG REF LEVEL to -30
AMPL CAL
See System Test and Troubleshooting
dBm (-30 +0). Adjust AMPL
does not vary
Procedure in 8552 Operating and
CAL so that the top of the signal
signal level.
Service Manual.
is exactly on the LOG REF (top)
graticule of the CRT. Proceed to
test 15.
15.
Set LOG/LINEAR to LINEAR
AMPL CAL
See System Test and Troubleshooting
and LINEAR SENSITIVITY to
can not be
Procedure in 8552 Operating and Ser-
1 mV/Div. The CRT deflection
adjusted for
vice Manual and Service Sheet 3. Probable
should be adjusted by the AMPL
7.07 division
trouble is in linear amplifier compensation
CAL control to 7.07 divisions.
display
circuit or 8552 Lin/Log Amplifier Assy.
If display is correct proceed to
test 16.
16.
Set analyzer controls as follows:
See System Test and Troubleshooting
SCAN WIDTH ................ 0-100 MHz
Procedure in 8552 Operating and
SCAN WIDTH
Service Manual.
PER DIVISION .................... 10 MHz
BANDWIDTH ....................... 10 kHz
LOG/LINEAR .......................... .LOG
LOG REF LEVEL............... -10 dBm
Turn BASE LINE CLIPPER
Bottom two
Check base line clipper circuit.
full ccw.
divisions of
CRT not
blanked.
Switch SCAN TIME PER
Scan does
Check scan generator circuit.
DIVISION through its range.
not occur in
all positions
Return SCAN TIME PER DI-
VISION to 2 ms.
Set SCAN WIDTH to PER
DISPLAY
Refer to Service Sheet 12. Probable
DIVISION
UNCAL does
cause of trouble is in the analogic circuit
not illuminate
or switching circuits.
Check DS1.
8-19
