Sharp VC-MH85 (serv.man4) Service Manual ▷ View online
50
VC-MH705HM/LM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
YES
YES
NO
Is there signal at pin (100) of IC201?.
Are there MH-AA
harness and the PB
AMP
peripheral parts normal?
No linear sound playback (E-E mode is possible)
NO
Is the azimuth height of
A/C head properly
adjusted?
Check the
AUDIO MUTE (H) line between
pin (99) of IC201 and pin (81) of IC701.
NO
Is there "L" level at pin (99) of IC201.
Is there signal at pin (1
1) of IC201.
YES
YES
Replace IC201.
Clean A/C
head.
Replace A/C
head.
Replace IC201.
Re-adjust azimuth.
NO
YES
YES
YES
YES
PA
L
E
P
ONL
Y
Are there signal at pin(1) of
IC601?
YES
NO
Hi-Fi model ONL
Y
Is there audio signal inputted at
and pin(62) of IC651.
Check line between pin(1
1) of IC201
and pin(62) of IC651.
FLOW CHART NO.25 LINEAR SOUND MODE TROUBLESHOOTING(2)
51
VC-MH705HM/LM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
YES
YES
NO
NO
NO
NO
YES
FLOW CHART NO.26 NICAM/IGR TROUBLESHOOTING
NO
NO
YES
YES
YES
YES
YES
IC1701?
Check peripheral circuit of X1701.
YES
YES
Check peripheral circuit of
TU101.
Check between SIF OUT
of
TU101
and pin(2) of IC1701.
Check between IIC Data
pins(26),(27) of IC701 and
pins(12),(13) of IC1701.
NO
NO
Is there a base band signal at SIF
OUT
of
TU101?
Is there a NICAM/IGR audio signal
at pins(31), (30) of IC1701?
Is there a NICAM/IGR audio signal
at pin(15),(16) of IC2501?
Is there a base band signal at
pin(2) of IC1701?
Check line between pin(39), (40) of
IC2501 and pins(9), (14) of IC651.
See Flow Chart No.21 Hi-Fi SOUND
MODE TROUBLESHOOTING
(1)
For Hi-Fi model
Is 5V supplied at pins(1
1),(19),(1) of
Check PC 5V line.
Is MPX 8V supplied at pin(33) of IC1701?
Check the REG. circuit of D962.
Check PC Motor 12V line.
Check peripheral circuit of IC1701.
Replace IC1701.
Check serial data and clock at
pin(12) and (13) of IC1701.
Is there oscillated 18.432MHz at
pins(5), (6) of IC1701?
No NICAM/IGR sound.
52
VC-MH705HM/LM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
FLOW CHART NO.27 DECODER TROUBLESHOOTING
SELECT
OUTPUT
INPUT
SIGNAL
OUTPUT
SIGNAL
<Hi-Fi
Audio Double scart>
MODE
SIG.
DECODER CIRCUIT
SIG.
FLOW
INPUT
FLOW
(A)
Pin47 of IC701(Y/C video output
E2(L2) video input
Front video input
pin7
pin28
pin25
E1(L1) video output
21PIN CONNECT
OR
(B)
(C)
pin13
pin2
E1(L1) audio output (L-ch)
(A)
(B)
E2(L2) audio input(L/R-ch)
Pin54 of IC651(Audio output R-ch)
pin33
pin1
1
pin1 E1(L1) audio output(R-ch)
pin42
21PIN CONNECT
OR
(C)
(A)
(B)
E2(L2) audio intput(R-ch)
pin34
pin10
pin18 E2(L2) video output(L-ch)
pin43
21PIN CONNECT
OR
(C)
(A)
(B)
E1(L1) video input
Pin47 of IC701(Y/C video output)
pin23
pin7
pin16
pin26
21PIN CONNECT
OR
(C)
(A)
(B)
E1(L1) audio input(L-ch)
pin36
pin2
pin15
pin30
(C)
(A)
(B)
pin37
(
C)
pin1
(A) E2(L2) video input
pin28
(B) E1(L1) video input
pin23
(C)
T
uner video output
pin18
(D)
pin13
(A) E2(L2) audio input(L-ch)
pin33
(B) E1(L1) audio input(L-ch)
pin36
(C) MPX output(L-ch)
pin16
(D)
pin1
1
(A) E2(L2) audio input (R-ch)
pin34
(B) E1(L1) audio input (R-ch)
pin37
(C)
pin15
(D)
pin10
NO
NO
NO
YES
YES
YES
Check STBY
5V line.
Check STBY
12V line.
Check line between pins(21), (22)
of IC2501 and pins(17), (18) of
IC701.
Is there SDA
and SCL
signal
applied to pins(21) and (22) of
IC2501?
Is voltage 5V applied to the video
section power terminal at pins(24),
(29) of IC2501?
Is voltage 12V applied to the
audio section power terminal at
pins(14) of IC2501?
Check signal line from video and
audio function logic table as shown
below
.
Not output from 21pin connector in video and audio signal.
Pin57 of IC651(Audio output L-ch)
T
uner video output
MPX output(L-ch)
Pin57 of IC651(Audio output(L-ch))
21PIN CONNECT
OR
E2(L2) audio output (L-ch)
pin31
E2(L2) audio output (R-ch)
21PIN CONNECT
OR
Pin31 of IC201
Y/C video input
(Aux. input)
Pin61 of IC651
(Aux. input
Pin52 of IC651
(Audio input (R-ch)
pin5
pin39
pin40
Front audio L-ch input
Front audio R-ch input
Front audio L-ch input
Front audio R-ch input
MPX output (R-ch)
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MPX output(R-ch)
Front video input
(switch)
E1(L1) audio input(R-ch)
Pin54 of IC651(Audio output R-ch)
53
VC-MH705HM/LM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
VC-MH815HM/LM,MH85HM
VC-MH715HM,MH835HM
REPLACEMENT OF IC710(E
2
PROM)
Servicing precautions
When the IC710(E
2
PROM) has been replaced, make the following reprogramming.
Depending on models, the IC710(E
2
PROM) has been factory adjusted for it s memory function.
It s therefore necessary to reprogram the memory function for the model in question.
Note that the servo circuit requires readjustments for the slow and still modes.
Note that the servo circuit requires readjustments for the slow and still modes.
1. Memory function reprogramming.
a. Check the power off.(Power is standby mode)
b. Make for moment short-circuit test point(TP801), located at the front side on the main PWB.
b. Make for moment short-circuit test point(TP801), located at the front side on the main PWB.
Be sure that all the display light up into the TEST mode.
c. Using the CHANNEL(+) AND (—) buttons, select the right function numbers from JP0 to JP39, which appear in the
display, referring to the E
2
PROM map.
Press the DISPLAY button to pickup the functions(ON) and the CLEAR button to discard the functions(OFF).
DISPLAY and CLEAR buttons, are located on the remote control unit.
DISPLAY and CLEAR buttons, are located on the remote control unit.
∗
when the DISPLAY button has been pressed (ON), the memory function number starts flashing.
∗
when the CLEAR button has been pressed (OFF), the memory function number lights up.
d. Example : "ON" and "OFF" are taken as "1" and "0" respectively.
The numbers JP0 to JP39 are divided into four groups and each group s setting is displayed in hexadecimal notation.
JP27 JP26 JP25 JP24
1
1
0
0
↓
C
JP23 JP22 JP21 JP20
0
0
0
0
↓
0
JP19 JP18 JP17 JP16
0
0
0
0
↓
0
JP15 JP14 JP13 JP12
0
1
0
0
↓
4
JP11 JP10 JP9 JP8
0
0
1
1
↓
3
JP7 JP6 JP5 JP4
0
0
0
0
↓
0
JP3 JP2 JP1 JP0
0
0
0
0
↓
0
Also recording level preset number selected from the ten keys on the remote control unit which appear in the
LCD display, referring to the E
LCD display, referring to the E
2
PROM map.
JP39 JP38 JP37 JP36
0
0
0
0
↓
0
JP35 JP34 JP33 JP32
0
0
0
1
↓
1
JP31 JP30 JP29 JP28
0
0
0
0
↓
0
SP n
∗
∗
↑
selection from the
ten keys.
(from "0" to "7")
ten keys.
(from "0" to "7")
EP n
∗
∗
↑
selection from the
ten keys.
(from "0" to "7")
ten keys.
(from "0" to "7")
Out lights
blank
SP p
∗
∗
↑
selection from the
ten keys.
(from "0" to "7")
ten keys.
(from "0" to "7")
LP p
∗
∗
↑
selection from the
ten keys.
(from "0" to "7")
ten keys.
(from "0" to "7")
2. Memory recording preset level reprogramming.
a. Similarly to the above step 1-a and 1-b the same operate.
b. Using the CHANNEL (+) AND (-) buttons, select the right function numbers continued from recording preset number
b. Using the CHANNEL (+) AND (-) buttons, select the right function numbers continued from recording preset number
as has been JP0~JP39, which appear in the LCD display, referring to the E
2
PROM map.
3. Example :
System
p : PAL
n : NTSC
n : NTSC
↓
Tape speed
→
LP or EP
n
∗
∗
↑
↑
Chrominance preset number. (from "0" to "7")
Luminance preset number. (from "0" to "7")
3. Finally make for a moment short-circuit test point(TP801), located at the front side on the main PWB to clear the
TEST mode.
↑
↑
↑
↑
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