Rf Pattern Testing - NAD C 541 Service Manual

RF PATTERN TESTING

TESTING PROCEDURE
(1) Load the test disc (Sony Test CD YEDS-7) and set the unit into PLAY mode.
(2) Connect the scope to R132 (Pin 41 of U101) and DGND (J334).
Scope setting:
(3) Observe the waveform is 2.0V p-p +/-5% and the eye pattern is at its best shape (see FIG. 1).
FIG. 1 (a)
3T 4T 5T — 11T
Testing Point
NAD - C 541 PCB TESTING POINTS DIAGRAM
Coupling
Vertical sensitivity
Horizontal time base
R132
: AC.
: 0.2 V/ div.
: 0.5 µS/div.
FIG. 1 (b) Poor eye pattern
FIG. 1 (C) Good eye pattern
9
Testing
Point
J334