Precor C960 Service Manual page 5

C960 Series Commercial Treadmill
SCR and PWM Upper PCAs
Note:
Upper PCA part number 33663-10X is used on C960s & C962s. Upper PCA part number 33662-
10X is used on C964s. There are currently three versions of the upper PCA that may be
encountered in the field. Versions -101 through 105 were only used on SCR treadmills and have
a fixed 11 MHZ clock frequency. Treadmills manufactured starting October 10, 1995 used the
version -106. Theses boards could be used on either SCR or PWM treadmills and could be set
for either 11 MHZ (SCR) or 16 MHZ (PWM) operation (see diagram 1.1). On August 6, 1997 on
version -108 the jumper selection was changed to indicate SCR or PWM (see diagram 1.2).
Diagram 1.1 - UPCA jumpers versions -106 & -107
Diagram 1.2 - UPCA jumpers versions -108 and higher
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