Hitachi 50V500/LC37, 60V500A/LC37 (NTSC) System TV adjustments - Power board circuit diagram

Lamp replacement, memory initialization SMPS schematic, Factory reset and more ..

Leakage Current Hot Check
Plug the AC line cord directly into a 120V AC 60Hz outlet (do not use an isolated transformer for this check). Turn the AC power ON. Using a Leakage Current Tester (Simpson’s Model 228 or equivalent), measure for current from all exposed metal parts of the cabinet (antennas, screw heads, overlays, control shafts, etc.) particularly any exposed metal part having a return path to the chassis or to a known earth ground (water pipe, conduit, etc.). Any current measured must not exceed 0.5 MIU.

Leakage Current Cold Check
With the AC plug removed from the 120V AC 60Hz source, place a jumper across the two plug prongs. Using an insulation tester (DC500V), connect one lead to the jumper AC plug and touch the other lead to each exposed metal part (antennas, screw heads, metal overlays, control shafts, etc.), particularly any exposed metal part having a return path to the chassis should have a minimum resistor reading of 2.4M and a maximum resistor reading of 5.2M. Any resistance value below or above this range indicates an abnormality which requires corrective action. An exposed metal part having a return path to the chassis will indicate an open circuit.

The lamp in this product contains Mercury.  Dispose of properly in accordance with applicable environmental laws. For Recycling and Disposal information, contact your respective governmental agencies or the Electronic Industries Alliance at www.eiae.org (in the U.S.) or Electronic Product Stewardship Canada at www.epsc.ca (in Canada).

Electrostatically Sensitive (ES) Devices
Some semiconductor (solid state) devices can be damaged easily by static electricity. Such components commonly are called Electrostatically Sensitive (ES) Devices. Examples of typical ES devices are integrated circuits and some field-effect transistors and semiconductor “chip” components. 

LAMP REPLACEMENT

Lamp Life

The lamp life may vary based on usage of the LCD Rear PTV. Turning on and off frequently may shorten the life of the lamp.

Lamp Replacement
After extended use, if the TV picture turns dark, the color looks unusual or LAMP INDICATOR light turns on, then it is time to replace the lamp with a new lamp.

The lamp gets very hot. The lamp may explode if improperly handled. To avoid injury, please observe the following
precautions.
✓ Do not open lamp compartment or attempt to remove lamp assembly unless the lamp assembly is being replaced.
✓ Unplug the product’s power cord from the AC outlet before attempting to replace the lamp assembly.
✓ If the lamp is in use when failure occurs or if the lamp has exploded, wait at least 30-45 minutes for the lamp to cool before opening the lamp compartment or touching the lamp assembly or any broken pieces.
✓ Broken lamp pieces can cause injury. Handle with gloves to avoid cuts.
✓ Do not place any foreign objects inside the lamp compartment.
✓ When installing a new lamp, follow handling instruction included with the new lamp. Do not touch glass surface of new lamp.
✓ The lamp in this product contains Mercury. Dispose of properly in accordance with applicable environmental laws. For Recycling and Disposal information, contact your respective governmental agencies or the Electronic Industries Alliance at www.eiae.org (in the U.S.) or Electronic Product Stewardship Canada at www.epsc.ca (in Canada).
CAUTION
 ”LAMP” indicator will light when lamp becomes hot. Unplug product’s power cord from the AC outlet and allow lamp to cool for at least 30-45 minutes. If “LAMP” indicator is still lit, check the lamp unit assembly.

TYPE NAME: LC37 LAMP ASSEMBLY
PART NUMBER: UX21511

Power board schematic

P.W.B. ADJUSTMENT

Memory Initialization: Adjustment Procedure
∆ Enter I2C mode from the front panel by pressing and holding the INPUT and the POWER button for two seconds, then release.
Note: When entering the I2C menu mode, make sure to wait about two minutes after power off. If entering the I2C menu mode immediately after power off, the I2C menu page will appear but remote control operation will not work.
∆ Receive signal on the main picture. (NTSC, SDTV or HDTV).
Some menu pages have I2C adjustments for SDTV and HDTV. 

The set will automatically allow you to set these items only when a SDTV or HDTV signal is input to the COMPONENT jacks on the back of the TV.

∆ Check the OSD using , buttons on the Remote Control to scroll down and cursor [right]  and hold for two seconds to enter the selected Device.

∆ Press the EXIT button to exit I2C ADJUST mode.
∆ Press the EXIT button again to EXIT the I2C menu.

FACTORY PRESET (1)
✓ Cursor right  to select factory reset (Fact Reset) of the OSD and check that the set returns to delivery settings (CH 03).
✓ Do not unplug the set until this operation is completed and do not perform any key operation either, after this operation each setting is resets  automatically.

[When exchanging microprocessor and TV is turned on for first time, it requires initialization of Memory Initial of I2C. 

Enter to I2C Adjustment mode and reset Memory Initialize.]

RGB Amplitude Adjustment
Preparation for adjustment
(1) Recall user menu and select ‘Video’ _ ‘Picture Mode’ _ ‘Day’ _ ‘Reset’.
(2) Input 525p(480p) of RGB amplitude adj. signal into INPUT1 (Component) input.
Adjustment procedure
(1) Receive 525p(480p) signal (ASPECT 16:9 Standard).
(2) Select ‘RGB (480P)’ from Service Adj. Menu.
(3) Press and hold the “RIGHT ” cursor on the remote for 2 seconds or more to perform automatic adjustment.
(4) Wait until ‘Auto Adjusting’ OSD is disappeared.

Sub-contrast adjustment

-Preparation
* Receive Sub-contrast adjustment signal.
-Adjustment
(1) Select ‘SUB CONTRAST’ of Service Adj. Menu.
(2) Press “RIGHT" for over 2 seconds to perform automatic adjustment. When it’s completed, ‘Auto Adjusting’ on the screen will be disappeared.