Rolsen RL-20S10, Руководство по обслуживанию

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RL-20S10 SERVICE MANUAL
PAGE:
13
ADJUSTMENT
1.Safety Precautions
1. Never disconnect leads while the TV receiver is on.
2. Don't short any portion of circuits while power is on.
3. The adjustment must be done by the correct appliances. But this is changeable in view
of productivity.
4. Unless otherwise noted, set the line voltage to 230Vac 10%, 50Hz ./ 110Vac, 60Hz
2.Test Equipment required
1. RF signal generator (with pattern generator)
2. Multi meter (volt meter)
3. Oscilloscope
4. LCD Color analyzer
3.RF AGC (Automatic Gain Control) Adjustment
Note!! Adjust a RF AGC of world standard tuner only.
2 in 1 tuner need not AGC adjust.
The RF AGC was aligned at the time of manufacture for optimum performance over a wide
range conditions. Readjustment of RF AGC should not be necessary unless unusual local
conditions exist, such as ;
1) Programme interference in a CATV system.
2) Picture bending and/or color beats, which are unusually due to excessive RF signal
input when the receiver is too close to a transmitting tower or when the receiver is
connected to an antenna distribution system where the RF signal has been amplified. In
this case, the input signal should be attenuated (with pad or filter) to a satisfactory level.
3) Picture noise caused by "broadcast noise" or weak signal. If the broadcast is "clean"
and the RF signal is at least 1mV (60dBu), the picture will be noise free in any area.
Adjusting RF AGC to one end of rotation will usually cause a relatively poor signal to noise
ratio; Adjusting to the other end of rotation will usually cause a degradation of over load
capabilities resulting in color beats or adjacent Programme interference.
Adjustment Note!!
1. Connect RF signal (65dB± 0.5dB) and turn on the TV.
2. Press MENU buttons on TV set and Remote Controller at the same time to get into
SVC mode.
3. Press YELLOW button on the Remote Controller several times to find AGC.
4. Press Volume UP/DOWN button until the AGC Voltage is the same as the Table
below.
5. Press OK button to memorize the data.
6. Press TV/AV button to exit SVC mode.