Sony BVH-2000, Руководство по эксплуатации и обслуживанию

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(5-7-6. R L-12 Board)
3. Reel Tension AC Feedback loop
Frequencies created by resonance between the tension arms,
of
for the CPU and are therefore handled by an AC feedback loop
A frequency beyond the band used by the servo system is used
onto the control signal as the carrier, in the low-pass filter so
The tape tension is detected by the potentiometers connected to
S T it
IT board The tape tension signals are converted into
unbalanced first
then input into the AC feedback loop.
The
variable attenuators, and amplifiers. The unstable elements
which the of the
springs and reels bring to the loop are compensated by the
compensators. variable attenuator compensates
the fluctuation of the frequency response caused by the reel
inertia and tape diameter, and controls the
gain in accordance with the amplitude characteristics. This is a
PWM type of variable attenuator and its on/off ratio is switcned
the CPU and its attenuation level is varied
Je2L (CTC) is triggered by the clock pulses with a frequency of
the 10MHz clock pulse input into pin-34A JC2L counts
2.5 and
pulse corrresponding to the value loaded into IC2L can be
BVH-2000(U/C)/PS/PM
BVH-2180( U/C)/PS/PM
SERVO SYSTEM
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