Standard Circuit Diagram - JVC AV28BT7ENS Service Manual

AV28BT7ENS / AV28BT7ENB
AV28BT7EES / AV28BT7EEB
AV28BT7EPS / AV28BT7EPB
WAVEFORM DIAGRAMS
MAIN PWB
Q802 D IC401 6pin
8Vp-p(H) 1.7Vp-p(H)
IC401 17pin IC401 30pin
0.7Vp-p(H) 0.8Vp-p(H)
IC401 20pin IC401 21pin
2Vp-p(H) 2Vp-p(H)
IC401 47pin IC701 1pin
0.6Vp-p(V) 4.8Vp-p(V)
CRT SOCKET PWB
IC901 7pin IC901 8pin
35Vp-p(H) 35Vp-p(H)
2-4
IC050 6pin IC050 17pin
0.7Vp-p(H) 1.4Vp-p(H)
IC401 29pin IC401 19pin
0.9Vp-p(H) 2Vp-p(H)
IC401 40pin Q605 C
1Vp-p(H) 450Vp-p(H)
IC701 9pin IC501 34pin
0.5Vp-p(V) 1.2Vp-p
IC901 9pin
35Vp-p(H)
No.51883
AV28BT7ENS / AV28BT7ENB
AV28BT7EES / AV28BT7EEB
AV28BT7EPS / AV28BT7EPB

STANDARD CIRCUIT DIAGRAM

NOTE ON USING CIRCUIT DIAGRAMS
1.SAFETY
The components identified by the symbol and shading are
critical for safety. For continued safety replace safety critical
components only with manufactures recommended parts.
2.SPECIFIED VOLTAGE AND WAVEFORM VALUES
The voltage and waveform values have been measured under the
following conditions.
(1)Input signal : Colour bar signal
(2)Setting positions of
each knob/button and
: Original setting position
variable resistor
when shipped
(3)Internal resistance of tester
:DC 20k /V
(4)Oscilloscope sweeping time
:H 20µS/div
:V 5mS/div
:Others
Sweeping time is
specified
(5)Voltage values
:All DC voltage values
Since the voltage values of signal circuit vary to some extent
according to adjustments, use them as reference values.
3.INDICATIONS ON THE CIRCUIT DIAGRAM
(1)Resistors
Resistance value
No unit :[ ]
K :[K ]
M
:[M ]
Type
No indication :Carbon resistor
OMR :Oxide metal film resistor
MFR :Metal film resistor
MPR
:Metal plate resistor
UNFR
:Uninflammable resistor
FR :Fusible resistor
Composition resistor 1/2 [W] is specified as 1/2S or Comp.
(2)Capacitors
Capacitance value
1 or higher :[pF]
less than 1
:[µF]
AV28BT7ENS / AV28BT7ENB
AV28BT7EES / AV28BT7EEB
AV28BT7EPS / AV28BT7EPB
Withstand voltage
No indication :DC50[V]
Others :DC withstand voltage [V]
AC indicated :AC withstand voltage [V]
Electrolytic Capacitors
47/50[Example]:Capacitance value [µF]/withstand voltage[V]
Type
No indication :Ceramic capacitor
MM
:Metalized mylar capacitor
PP :Polypropylene capacitor
MPP
:Metalized polypropylene capacitor
MF :Metalized film capacitor
TF :Thin film capacitor
BP
:Bipolar electrolytic capacitor
TAN
:Tantalum capacitor
(3)Coils
:[ µ H]
No unit
Others :As specified
4.NOTE FOR REPAIRING SERVICE
This model's power circuit is partly different in the GND. The
difference of the GND is shown by the LIVE side GND and the
ISOLATED(NEUTRAL) side GND.Therefore, care must be
taken for the following points.
(1)Do not touch the LIVE side GND or the LIVE side GND and the
ISOLATED(NEUTRAL) side GND simultaneously. If the above
caution is not respected, an electric shock may be caused.
Therefore, make sure that the power cord is surely removed from
the receptacle when, for example, the chassis is pulled out.
(2)Do not short between the LIVE side GND and ISOLATED(NEUTRAL)
side GND or never measure with a measuring apparatus measure
with a measuring apparatus ( oscilloscope, etc.) the LIVE side GND
and ISOLATED(NEUTRAL) side GND at the same time.
If the above precaution is not respected , a fuse or any parts will be broken.
Since the circuit diagram is a standard one, the circuit and
circuit constants may be subject to change for improvement
without any notice.
NOTE
Due improvement in performance, some part numbers show
in the circuit diagram may not agree with those indicated in
the part list.
When ordering parts, please use the numbers that appear
in the Parts List.
Jan. 2002 No. 51883