Set-Up For Adjustment; Crt Adjustment - Aiwa TV-AS215NH Service Manual

ADJUSTMENT

Set-Up For Adjustment

Because the video signal output from a pattern generator is used as the
adjustment signal input during adjustment, the video signal output from
the pattern generator must conform with the specifications. Measure the
output waveform across 75 Ω load. Confirm that the synchronizing signal
has an amplitude of about 0.3 V, the video signal portion has an amplitude
of about 0.7 V and the burst signal has an amplitude of about 0.3 V with
flat envelope. Confirm that ratio of the burst signal amplitude and the
red signal amplitude is 0.30 : 0.66. If the output signal does not conform
with the specifications, calibrate the pattern generator. (Refer to pattern
generator operation manual.)
Use the LEADER: LCG 404 for the pattern generator.
Approx. 0.7V
1 Vp-p White (Approx.
75%)
Approx. 0.3V
Color bar signal of a pattern generator
Precautions Before Starting Adjustment
Satisfy the following setting conditions before starting adjustment.
• Allow warm-up of 20 minutes or longer. (Do not turn off during warm-
up.)
• Set all picture quality controls of users' setting to initial set-up, unless
otherwise specified.
• Picture quality reset
1. Select "Picture" on the screen menu and press enter button.
2. Select "Normal" and press enter button.
3. Select "Reset" and press enter button.
• Set the pattern generator's output level to 1.0Vp-p (across 75Ω load).
TV display

1. CRT Adjustment

1-1. Precautions
(1) Receive the white raster signal, and then perform aging for at least
20 minutes.
(2) Demagnetize the area surronding the CRT with a degausser before
making adjustments.
(3) Set the picture quality for each mode to the factory setting.
(4) Position the front screen facing the east as much as possible.
1-2. Purpose
(1) Beam landing adjustment (purity magnet)
Set the left/right balance of beam landing. If there is a discrepancy
in this adjustment, a color irregularity will occur. After completion
of the landing adjustment, it is necessary to perform convergence
adjustment.
Burst signal
Before adjustment
Approx.
0.3V
– 8 –
After adjustment
Color Color
Color
irregularity irregularity
Fig. 1-1