Sharp 20CT-250 Service Manual page 10

FUNCTION CHECK (VIDEO AND AUDIO)
No. Adjusting point Adjusting procedure/conditions
1 Contrast key 1. Receive the E-5CH signal.
2. Select the contrast on the P-MODE screen.
3. Check whether the Contrast is OK or not with Up/
Down keys.
2 Colour key 1. Receive the E-12CH signal.
2. Select the colour on the P-MODE screen.
3. Check whether the Colour is OK or not with Up/
Down keys.
3 Brightness 1. Receive the E-5CH signal.
key 2. Select the brightness on the P-MODE screen.
3. Check whether the Brightness is OK or not with
Up/Down keys.
4 Tint key 1. Receive the NTSC colour bar signal. (A/V In Only)
2. Select the tint on the P-MODE screen.
3. The tint must be changeable toward green with
the UP key and toward red with the DOWN key.
5 PIC-Normal. 1. Press the Normal key on the P-MODE screen to
key make sure all the displayed items are at normal
settings.
See below for the normal settings.
» Contrast
: MAX
» Colour
: CENTER
» Brightness : CENTER
» Tint
: CENTER
» Sharpness : CENTER
6 Sharpness key 1. Receive the E-5CH signal.
2. Select the sharpness on the P-MODE screen.
3. Check whether the Sharpness is OK or not with
Up/Down keys.
Waveform and others
* The contrast, colour, brightness,
tint and sharpness settings are
all normal when these items do
not appear on the screen.
10-1
No. Adjusting point Adjusting procedure/conditions
7 Channel sign 1. The display colour of all the channel (0-99) signs
display colour must be green Under the AFT on mode.
8 COLOUR 1. Receive the NTSC 3.58 colour bar (A/V) signal.
SYSTEM key Using the COLOUR SYSTEM key, select a mode
other than N3.58 and make sure the colour sys-
tem does not work properly.
9 Bilingual Key 1. Receive Bilingual sound signal, press the "Bilin-
gual" key. Check whether there is change
SOUND-1 to SOUND-2.
10 Noise mute 1. Receive the PAL Colour Bar signal.
check 2. Turn up the sound volume to maximum and make
sure the sound is heard normally from the speak-
ers. Then cut off the signal.
3. Make sure the sound muting functions.
4. Finally turn down the sound volume to minimum.
Waveform and others
10-2