Check +14V Short Protection Circuit; Load Short Protection Circuit Operation Check; Weak Electric Field Check; Remo-Con Operation Check - Hitachi 36UX59B Service Manual

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R906
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4. CHECK + 14V SHORT PROTECTION CIRCUIT.
Adjustment Preoaration
(1) Set "CONTRAST" to maximum and
"BRIGHTNESS to center.
Adjustment Procedure
(1) Connect a 47kD 1/8W Resistor between Q909
base and ground, check that picture disappears.
R952
ih!
47kfi 1/8W Resistor
To D939
(2) Immediately disconnect the power cord.
(3) Discharge C905A as follows.
R906
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5. LOAD SHORT ;ROTEC;ION CIRCUIT
OPERATION CHECK.
Adiustment Procedure
(1) Receive circle pattern signal.
(2) Set "CONTRAST" to maximum and
"BRIGHTNESS" to center.
(3) After turning on the CTV set, confirm the DC
voltage of D008, DOOF, D753 and D952, each
cathode side. These voltages should be more
than 1.5V.
(4) Short-circuit both ends of R961 and check that
the picture disappears within 2-3 sec.
(5) Disconnect short-circuit of R961 and the TV set
power cord.
(6) Discharge C905A as follows.
R906
6. WEAK ELECTRIC FIELD CHECK
Adjustment Preoaration
(1) Connect one side of the 300 ohm feeder to 75
ohm - 300 ohm antenna adapter. Connect the
antenna adapter to the VHF antenna terminal
board as shown below.
(2) Turn to no signal condition.
Adiustment Procedure
(1) Check that the phenomena such as oscillation
and abnormal beat, etc. do not occur in all the
channel.
/Antenna Terminal board
&GZZOO ohm adaptor
VI. REMO-CON OPERATION CHECK
1. DIRECT CHANNEL SELECTION
Adiustment Procedure
(1) Input 2 or 3 digits of channel number with the
buttons of the Remo-con "O-9." Check that the
input number and the on-screen display number
are the same. (At 1 OOCH selection, press "1" and
after 2 seconds, press "0" two times.
l---l---
After
2 seconds
2. LST-CH (LAST CHANNEL RECALL)
Adiustment Procedure
(1) Check that the set receiver alternates between
the channel which is being received and the
channel which was previously received with each
press of the "LST-CH" button of the Remo-con.
3. MUTE
Adiustment Procedure
(1) Check that the sound alternates between SOFT
MUTE, MUTE and MUTE OFF by every pressing
of "MUTE" button on the Remo-con. At this time,
check the MUTE indication:
MUTE off Yellow
SOFT MUTE Magenta
MUTE Magenta
(2) Check that sound level goes to l/2 level at SOFT
MUTE.
(3) Check that sound level goes to 0 at MUTE mode.
4. EXIT/RECALL/CS
Adiustment Procedure
(1) Check that on-screen channel no. indication
and the COMMERCIAL SKIP Icon appears by
pressing the "EXIT/RECALL/CS" button of the
Remo-con.
5. P IN P
Adiustment Preparation
(1) Connect signal to ANT A and receive it.
(2)
39
Connect signal to VIDEO: 1 Input.