BELINEA 10 55 70, Руководство по обслуживанию

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Transistor ON
(a) Base Input voltage
(b) Current through transistor
(c) Current through diode
(d) Capacitor current
(e) Current through deflection yoke
Voltage generated in deflection yoke
3-7 Horizontal Output Voltage/Current Waves
curve to the linear ramp, resulting in
linearity errors in the displayed image.
In addition to the AC coupling of the deflection
yoke, another major difference is that the
damper diode is split into two diodes. A second
resonant circuit comprising of
and
are connected at this point. This second reso-
nant circuit acts exactly as a smaller version of
the
circuit. A ramp current is set up in
proportional to the voltage at output
of the diode modulator circuit, VDM. A small
voltage is also created across as
a result of this. Consequently, voltage
across the yoke winding is the difference
tween the constant heigh main
seen across and smaller, variable
pulse seen across As the current
flowing in the yoke is proportion to this differ-
ence, the deflection current (and therefore the
VDM. This voltage is derived from the output
of 4353 after buffering by a unity voltage gain
amplifier formed by 4354 and 4355.
The voltage seen in the output stage require
special attention. The B+ supply can varying
between
180. The main pulse seen
across and associated components is
around 1200V. Consequently, appropriate pre-
cautionary measures must be taken when serv-
icing the monitor.
In addition to the basic topology as
arc a
of
additional
dcviccs. and 4309 can bc
on or off logic control.
switch addition capacitors, C3 I3 and
C324 in parallel with C3 I to alter the amount
of ‘S’ correction at different horizontal scan
frequencies.
displayed image width) can hence D308 and D309 set up a positive and a negative
by varying the diode modulator voltage, supply rail with respect to the main B+ supply.