Adjustment Of The Electrical Circuits; Before Adjustment; If Adjustment Is Required; E Prom Setting - Sharp VL-A111S/H/E Service Manual

5. ADJUSTMENT OF THE ELECTRICAL CIRCUITS

5-1. BEFORE ADJUSTMENT

· Electric circuit adjustment becomes necessary, in most cases, when any of the wear mechanical parts or the video head has been
replaced. Before starting the electric circuit adjustment, be sure to check that the mechanical parts work well (i.e., the mechanical
parts have all been perfectly adjusted). In case a trouble or troubles are found in the electric circuitry, be sure to pinpoint the cause(s)
by using the measuring instruments described below. After locating the trouble spot(s), then proceed to repair, replacement or
adjustment. Do not change the positions of the controls when adequate measuring instruments are not available.
· In order to implement a higher-density, smaller machine, most of the electric circuit parts used on the Circuit Boards are of small-
sized, surface-mounted type. For replacing part(s) as after-sales, service, work with a soldering iron as speedily as possible. The
heat resistance of the surface-mounted components is poor, when compared with the larger-sized discrete parts used for television
sets and stationary decks, owning to their small sizes. Therefore, exercise due care to avoid long-time exposure of the pins of these
parts to the heat of the soldering iron which may possibly damage them. Such care should be exercised especially for chip-layer
capacitor replacement. It is advisable to use a temperature-controlled ceramic soldering iron (temperature at the tip: 250 C, contacting
time: less than 5 seconds).

5-2. If adjustment is required

The electric circuit needs to be adjusted if:
1 The mechanism (including H/A PWB) is replaced.
2 The lens (including CCD PWB) is replaced.
3 The LCD panel is replaced.
4 The main PWB is replaced.
5 E
2
PROM on the IC705 and IC002 are replaced.
2
5-3. E PROM setting
5-3-1. Data setting procedure
0) Remove the backup battery (CR2025).
1) Move the switch on the main unit to VCR for "VTR ADJ", and to CAMERA for "CAM ADJ".
2) Example: For "VTR ADJ" (Basic operations are the same as "CAM ADJ".)
1 After pressing the "CONTINUE" key on the service remote control (RRMCG0033TASA), press the "VTR ADJ" key.
2 Select the corresponding address using the "FF" or "REW" key on the service remote control, and confirm it with the "PLAY" key.
3 Select the target data with the "FF" or "REW" key and press the "PLAY" key to confirm the selection.
4 If you want to change other address data sequentially, press the "STOP" key and repeat steps 2 and 3.
1
VTR ADJ
0000
2
3) Data is written in E PROM by entering the stand-by mode and removing the AC adapter and battery.
5-3-2. [When IC705 is replaced]
1) Following the procedures to change E
2) Perform adjustment of electric circuit, head switching, recording current, audio circuit, and LCD circuit in this order.
5-3-3. [When IC002 is replaced]
1) Following the procedures to change E
2) Perform adjustment of the lens and then camera signal process.
2
VTR ADJ
0003 00
Flashing
2 PROM data, enter and confirm the address data in (Table 1) and (Table 2).
2
PROM data, enter and confirm the address data in (Table 3).
3
VTR ADJ
0003 60
Flashing stops with
"PLAY" key
21
VL-A111S/H/E/AH131S/H/E
VL-AH151S/H/E