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8-13
The H SIZE MAX has two area of memory (H SIZE MAX 1 and 2) which is selected by the below table.
H Frequency Range[KHz]
Selected Memory
101.0 - 115.0
H SIZE MAX 2
82.6 - 101.0
H SIZE MAX 2
69.5 - 82.6
H SIZE MAX 2
52.7 - 69.5
H SIZE MAX 2
49.0 - 52.7
H SIZE MAX 1
41.5 - 49.0
H SIZE MAX 1
36.6 - 41.5
H SIZE MAX 1
33.6 - 36.6
H SIZE MAX 1
30.8 - 33.6
H SIZE MAX 2
6) Rotation Correction Circuit
Raster rotation is corrected by moving the electron beam in the magnetic field produced by current applied
to the Z-coil. The amount of correction is proportional to the current applied to the Z-coil and the correction
can be adjusted with the control voltage (DC) of the D/A converter. The DC voltage output from IC532(D/A
converter) pin 15 generates current to flow in the Z coil, and amount of rotation is determined. User can
adjust the level of rotation by operating OSM menu (Rotate).
(Fig. 2.10) Rotation Correction Circuit
7) H Centering Circuit
Switching regulator generates the floating 5.5 volts which is compared to the deflection circuit power supply
voltage ( high B+ voltage). This voltage is divided by VR581 (H centering) and is supplied to the base of
Q581. The voltage differences of Q581's base and emitters is supplied to L562.
Horizontal centering is manipulated by the current supplied by L562 to the horizontal deflection circuit.