NAD T 975 C/AH, Service Manual, Page: 6 / 40

For example; all 7 channels at 50W/4 ohms for 10 minutes or 5 minutes or even less (as
long as the fan can starts turning). Turn off the signal but still keep the unit operating for 1
minute. Then run all 7 channels at 1kHz,
0.25W
at 4 ohms load, monitor the voltage at
TP1 J201. Adjust RV201 to get the voltage from negative to positive to ensure
that the Fans are turned off. Then run all 7 channels at 1kHz,
0.5W
at 4 ohms
load, monitor if the voltage at TP1 of J201 is negative, if not, adjust Pot RV201 just
to the point that TP1 changes from positive to negative (to get the fans just start turning).
Finally, turn off the signal and monitor if fans stop turning within about 30s Maximum.
- 6 -