NAD C660 Service Manual page 26

ALPC Logic circuit check
Execute 'E. LD On' of 'How to
use Test Tool (Dragon)':
'CD-R Recording Mode'
IC310 Pin 33 (CDR/RW) = "H"?
YES
IC310 Pin 34 (WR/RE) = "H"?
YES
IC310 Pin 27 (WGATE) = "H"?
YES
IC108 Pin 50 (WLDON) = "H"?
YES
Are
IC310 pin 29 (EFM1),
30 (EFM2), 42 (RESAMP1),
2 (RESAMP2), 41 (ROPC1)
pulse signals?
YES
Are IC108 pin
38 (WFPDSH), 39 (RFPDSH),
40 (WBLSH), 41 (SPDSH), 42 (MPDSH)
pulse signals?
YES
Are PN101
pin30 (ODON) 31 (W/XR)
pulse signals?
YES
Dragon : Execute LD 'off'
K
NO •Check the connection of IC320 pin 20.
•Check and replace the IC320.
•Check the connection of IC320 pin 7.
NO
•Check and replace the IC320.
•Check the connection of IC301 pin 166.
NO
•Check and replace the IC301.
•Check the connection of IC310 pin 13.
NO
•Check and replace the IC310.
•Check the connection lines of IC301.
NO
•Check and replace the IC301.
•Check the connection lines of IC310.
NO
•Check and replace the IC310.
•Check the connection lines of
NO
IC310 pin 21,18.
•Check and replace the IC310.
Dragon : Execute LD 'off'
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