Adjustment Procedure; Measuring Instruments; Preparatory Inspections - NEC DPro2070SB Service Manual

2.

Adjustment procedure

2.1

Measuring instruments

(1) Signal generator A:
(2) Signal generator B:
(3) DC voltmeter:
(4) High voltage meter:
(5) Luminance meter:
(6) AC voltmeter:
(7) Oscilloscope:
(8) Landing measuring device:
(9) Double scale:
(10)Withstand voltage meter:
(11)Grounding conductivity measuring instrument: CLARE U.K. product
(12)Convergence meter:
2.2

Preparatory inspections

(1) There must be no cracks or remarkable contamination on the PWB.
(2) There must be no remarkable lifting or inclination of the parts on the PWB, and the
parts must not be touching.
(3) The connectors must be securely inserted without crimping faults.
(4) The CRT socket, anode cap and focus lead must be securely mounted.
(5) The lead wires must not be pressed against the edges of the board.
(6) The lead wires must not touch the high temperature parts such as the R-METAL, R-
CEMENT or TR with FIN.
(7) The board must not be bent, remarkably contaminated or scratched.
(8) The CRT has no scratch or chipping.
(9) Each potentiometer must turn smoothly.
(10)Always set each potentiometer to the following positions before turning the power ON.
PWB name IC sources
PWB-MAIN
Astro Design VG-812 or equivalent
Astro Design VG-829 or equivalent
150V 0.5 Class or digital voltmeter
0.5 Class that can measure 40KV
Minolta color analyzer CA-100 or equivalent
150V/300V 0.5 Class or equivalent
Scope with band of 100MHz or more
Felmo product
For width and distortion measurement
Kikusui Model TOS8650 or equivalent
MINOLTA CC-100
Potentiometer default settings
Name (symbol)
VR5A1
H-POSI
FOCUS1
FOCUS2
SCREEN
PWB-MAIN
* look at inside of the monitor from upper side.
Default adjustment position Remarks
Center
Center
Center
Completely counterclockwise
BEZEL
CRT
VR5A1
DY
FBT
2 - 1
FBT
FBT
FBT