Alignment and Adjustments
4. Alignment and Adjustments
4-1 General Alignment Instructions
1. Usually, a color TV-VCR needs only slight5. Avoid overload. Excessive signal from a
touch-up adjustment upon installation. Checksweep generator might overload the front-end
the basic characteristics such as height, of the TV. When inserting signal markers, do
horizontal and vertical sync and focus. not allow the marker generator to distort test
results.
2. Observe the picture for good black and white
details. There should be objectionable color 6. Connect the TV only to an AC power source
shading; if color shading is present, with voltage and frequency as specified on the
demagnetize, perform purity and convergencebackcover nameplate.
adjustments described below.
7. Do not attempt to connect or disconnect any
3. Use the specified test equipment or its wires while the TV is turned on. Make sure
equivalent.that the power cord is disconnected before
replacing any parts.
4. Correct impedance matching is essential.
8. To protect against shock hazard, use an
isolation transformer.
4-2 Automatic Degaussing
A degaussing coil is mounted around theIf the chassis or parts of the cabinet become
picture tube, so that external degaussing aftermagnetized, poor color purity will result. If
moving the TV should be unnecessary. Butthis happens, use an external degaussing coil.
the receiver must be properly degaussed uponSlowly move the degaussing coil around the
installation.faceplate of the picture tube and the sides and
front of the receiver. Slowly withdraw the coil
The degaussing coil operates for about 1to a distance of about 6 feet before turning
second after the power is switched ON. If thepower OFF.
set is moved or turned in a different direction,
the power should be OFF for at least 10If color shading persists, perform the
minutes.following Color purity and Convergence
adjustments.
4-3 High voltage Check
CAUTION : There is no high voltage adjustment
on this chassis. The B+ power supply should be
+135 volts (with full color- bar input and normal
picture level).
1. Connect a digital voltmeter to the second
anode of the picture tube.
2. Turn on the TV. Set the Brightness and
Contrast controls to minimum (zero beam
current).
3. Adjust the Brightness and contrast controls to
both extremes. Ensure that the high voltage
does not exceed 32 KV under any conditions.
4-1 |
ACEC
