![background image](http://html1.mh-extra.com/html/viewsonic/a91f-1/a91f-1_service-manual_1020119005.webp)
5-4 Move the resistor connection to each exposed metallic part and measure the voltage.
5-5 Reverse the polarity of the AC plug in the AC outlet and repeat the above measurement.
5-6 Voltage measured must not exceed 7.5 volt RMS, from any exposed metallic part to ground A leakage current
tester may be used in the above hot check, in which case any current measured must not exceed 5.0 milliamp. In
the case of a measurement exceeding the 5.0 milliamp value, a rework is required to eliminate the chance of
shock hazard.
Note
:
High voltage is present when this CRT display is operating. Always discharge the anode of the picture
tube to the display chassis to prevent shock hazard.
AC VOLTMETER
TO
INSTRUMENT'S
EXPOSED
METAL PARTS
1500
Ω
10W
0.15
μ
F
Fig. 1
(EARTH
GROUND)
6.
IMPLOSION
PROTECTION
Picture tubes are equipped with an integral implosion protection system, but care should be taken to avoid damage and
scratching during installation.
Use only Panasonic replacement picture tubes.
7.
X-RADIATION
WARNING
:
The only potential source of X-Radiation is the picture tube. However when the high voltage circuit is
operating properly there is no possibility of X-Radiation problem. The basic precaution which must be exercised is to
keep the high voltage at the following factory-recommended level.
Note
:
:
:
:
It is important to use an accurate periodically calibrated high voltage meter.
7-1 The procedure for adjusting high voltage is shown on page 21.
7-2 If
can not be adjust 25.0 KV at
immediate service is required to prevent the possibility of premature
component failure.
7-3
To prevent X-Radiation possibility it is essential to use the specified picture tube.
IMPORTANT SAFETY NOTICE
There are special components used in this CRT displays
which are important for safety. These parts are identified
by the international symbol
!
on the s
c
hematic
diagram and on the replacement parts list. It is essential
that these critical parts should be replaced with
manufacture’s specified parts to prevent X-RADIATION,
shock, fire, or other hazards. Do not modify the original
design or this will void the original parts and labor
guarantee.
2
ViewSonic
Corporation
Co
nfidential
-
Do
Not
Copy
A91f+-1
Summary of Contents for A91f+-1
Page 27: ...1 2 3 4 5 6 24 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 28: ...7 8 9 10 11 12 25 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 29: ...13 14 15 16 17 18 26 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 30: ...19 20 21 22 23 24 27 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 31: ...25 26 27 28 29 30 28 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 32: ...31 32 33 34 35 36 29 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 33: ...37 38 39 40 41 42 30 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 34: ...43 44 45 46 47 48 31 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 35: ...49 50 51 52 53 54 32 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 36: ...55 56 57 58 33 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 41: ...C PCB defined 38 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 62: ...59 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 63: ...60 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 64: ...61 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 65: ...62 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 66: ...63 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 67: ...64 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 68: ...65 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 69: ...66 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 70: ...67 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 71: ...68 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 72: ...69 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 73: ...70 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 74: ...71 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 75: ...72 ViewSonic Corporation Confidential Do Not Copy A91f 1...
Page 76: ......
Page 77: ......
Page 78: ......
Page 79: ......
Page 80: ......
Page 81: ......
Page 82: ...79 ViewSonic Corporation Confidential Do Not Copy A91f 1...