NEC MultiSync V520 Service Manual page 64

11.Output of the parabola and bow-shaped parabola (Pin 14):
The amplitude and the polarity of the ramp signal are controlled by means of the PARA CNTRL (Pin
12), and the amplitude and polarity of the parabola are controlled by the BOW CNTRL (PIN 13).
In both cases, the control is carried out in the DC mode.
12.V Dyn Focus control (Pin 15):
The voltage is within the 0V to 4V range. When the voltage falls within the 2V-4V range, the parabola
becomes positive. On the other hand when the voltage falls within the 0V-2V range, the parabola
becomes negative.
13.V Dyn Focus (Pin 16)
14.ALC Cap (Pin 18):
This is the Automatic level Controller (ALC) capacitor, and the recommended value is 4.7 uF.
15.Frequency doubling capacitor:
This is the vertical oscillator that locks at a frequency twice as high as the vertical synchronization
frequency. Its capacitance is 0.47 uF.
16.OSC Cap (Pin 20):
The value of the capacitance is 0.1 uF.
17.Rvert (Pin 21/22):
The vertical resistor has the function of determining the gain of the vertical ramp current generator.
18.–V drive (Pin 23) and +V drive (PIN 24):
–V is the negative portion of the vertical ramp output current of the object of the operation.
The ramp current waveform is superimposed on the DC current of the approximately 315 uA.
The voltage corresponding to the output (typically 10 k
Ω
) is typically 6V.
61