Motorola R-20010 Maintenance Manual page 194

7 .2.5 INTENSITY CONTROL
The INTENSITY LEVEL signal from the front
panel control is gated with the SCOPE Z-AXIS signal
hy the intensity-level gate (Q6). The gated signal is
summed (U25) with the HIGH VOLTAGE REF and
INTENSITY SAMPLE VOLTAGE signals, to pro-
vide the INTENSITY TRACKING VOLTAGE (TV)
signal.
T he INTENSITY TV is the low-frequency
control path which drives the intensity opto-isolator in
the High-Voltage Supply.
7.2.6 FOCUS CONTROL
The FOCUS TRACKING VOLTAGE (TV) signal
is obtained by comparing the FOCUS LEVEL control
line to the FOCUS SAMPLE VOLT signal. The TV
signal drives an opto-isolator circuit in t he High-Volt-
age
Supply which controls the CRT focus voltage.
7-2
7.2.7 ASTIGMATISM, GEOMETRY, AND TRACE
ROTATION
The CRT alignment controls fo r astigmatism ,
geometry and trace rotation are obtained from the
respective wipers of three potentiometers . Each
potent iometer is connected between supply voltages
eq ual to the required adjustment range.