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TC-14RM12LP/TC-14RM12LP(.)/ TC-20RA12LP/TC-20RA12LP(.)/TC-20RM12LP/TC-20RM12LP(.)
ADJUSTMENTS
NECESSARY INSTRUMENTS:
ITEM / PREPARATION
PROCEDURE
BUZZING CONFIRMATION (AUDIO CIRCUIT)
1. Connect the oscilloscope with a 7kHz filter between the
speakers terminals L+ to G4-4, L- to G4-3, R+ to G4-1
and R- to G4-2.
2. Adjust volume control to maximum.
3. Adjust the others controls as above:
SOUND MENU
DIALOG
EQUALIZER
NORMAL
BALANCE
CENTER
HYPER BASS
OFF
LOUDNESS
OFF
AVL
OFF
SURROUND
OFF
CONFIRMATION
:
1.
Supply a colorbar signal with local frequency adjusted
and the AFC ON (Channel with sound bearer and without
modulation).
2.
Assure that the width in the buzzing waveform is smaller
than 500 m Vp-p.
RF AGC ADJUSTMENT
1. Supply a color bar PHILIPS pattern and adjust the RF
input signal of 69 dB mV (75W opened channel 7 RF
freq.: 175.25 MHz).
2. Connect the digital multimeter in TPA15.
ADJUSTMENT
:
1. Select “RF AGC” on “CHK2” service mode.
2. Adjust "RF AGC" by pressing VOL(+) or (-) until obtaining
2.2±0.1V in TPA15.
3. Increase the input level by +2 dB and confirm that the
voltage decreases in TPA15.
CONFIRMATION
1. Connect a voltage meter between TPA16 and ground and
confirm that the vB is within a range of 141,0V± 2V
2.
Connect a high frequency voltage meter (VRMS) among
the heater, and confirm that the voltage is
according to
the table below:
3.
Connect the high voltage meter in the CRT anode pin,
and confirm that the high voltage is be among 25,2~23KV
for 14” CRT and 27,2~25KV for 20" CRT .
ANODE AND HEATER VOLTAGE CONFIRMATION
1. Supply a crosshatch signal.
2. Adjust the current beam to zero. (0 beam).
3. Adjust “SCREEN VR” and “CONTRAST” to minimum.
Note:
(When using a high voltage meter resistive type, it is
necessary to use an electrostatic meter type to verify the
values)
14” 6,15 ± 0,25 Vrms
20” 6,15 ± 0,25 Vrms
PROTECTION CIRCUIT (SHUTDOWN)
CONFIRMATION OF OPERATION
1.
Supply a
crosshatch pattern
signal
and adjust the
CONTRAST and BRIGHT DAC controls to minimum.
(Ibeam=0
µ
A)
CONFIRMATION:
1. Connect the voltmeter in TPA22 and confirm that the
voltage is smaller than [
A
].
2. Connect a DC source in TPA22 and confirm that the
protection circuit doesn't act when the voltage is [
B
].
3. Confirm that the protection circuit acts with smaller voltage
than [
C
].
Condition
A
B
C
14”
22,8
23,9
26,7
20”
23,3
24,5
27,4
smaller than
500 m Vp-p
7K Hz Filter
• CW GENERATOR
• DUAL-TRACE OSCILLOSCOPE VOLTAGE RANGE
0.001 V TO 50 VDIV.
FREQUENCY RANGE DC TO 50 MHZ
PROBES 101, 11
• SPECTRUM ANALISER
• NTSC VIDEO PATTERN GENERATOR
• DVM (DIGITAL VOLT METER)
• POWER SUPPLY DC 30V
• ATENUADOR
• ISOLATION TRANSFORMER (VARIABLE)
• DEGAUSSING COIL
• WHITE PATTERN GENERATOR
• AUDIO GENERATOR
