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1
AKAI VS-G760
Matrix
Item
See Model
Book
Mechanical Adjustments ...................................................................... VS-G260
6
Mechanical Alignments ........................................................................ VS-G260
6
Deck Exploded View ............................................................................. VS-G260
6
Deck Parts List ...................................................................................... VS-G260
6
General Information
Also Covers
VS-G765, VS-G767,
VS-G770, VS-G771.
Recommended Safety Parts
Item
Part No.
Description
7
BT-435636N
TRANS POW V1252-M
30
ED-418622N
D SILICON 1N4006N02 T05 800/1 A
36
ED-422420J
D ZENER H MTZJ20C T26
46
EF-394702N
FUSE 218 TIME 250V 2.00A
95
ER-408829N
R FUSE VT05 RF25SCVTP1/4WR11K
96
ER-418648N
R FUSE VT05 RF25SCVTP1/4WR24K
97
ER-400729N
R FUSE VT05 RF25SCVTP1/4WR47K
98
ER-410380N
R FUSE VT05 RF25SCVTP1/4WR91K [SEG]
99
ER-435803N
R FUSE VT05 RF25SVTP1/4W 8R2J
104
ET-422113N
PHOTO COUPLER PS2561-1-V
137
ET-428371N
TR25C4908
138
ET-401091J
TR25D2144S U,V,WT05
C201
EC-422101N1
C MMY V CUT MKTR40 104M 275AC
C202
EC-422101N1
C MMY V CUT MKTR40 104M 275AC
C204
EC-435500N
C CE V CUT CS11 E222M 250AC [SEEK]
C205
EC-435500N
C CE V CUT CS11 E222M 250AC
C206
EC-435500N
C CE V CUT CS11 E222M 250AC
C207
EC-435500N
C CE V CUT CS11 E222M 250AC [SEEK]
C208
EC-435500N
C CE V CUT CS11 E222M 250AC
C209
EC-435500N
C CE V CUT CS11 E222M 250AC
C430
EC-418655N
C DBL LAYER T05 FM0H473Z 5.5DC
D201
ED-418622N
D SILICON 1N4006N02 T05 800/1 A
D202
ED-418622N
D SILICON 1N4006N02 T05 800/1 A
D203
ED-418622N
D SILICON 1N4006N02 T05 800/1 A
D204
ED-418622N
D SILICON 1N4006N02 T05 800/1 A
D227
ED-422420J
D ZENER H MTZJ20C T26
D242
ED-422420J
D ZENER H MTZJ20C T26
FR201
ER-435803N
R FUSE VT05 RF25SVTP 1/4W8R2J
FR202
ER-408829N
R FUSE VT05 RF25SCVTP 1/4WR11K
FR203
ER-400729N
R FUSE VT05 RF25SCVTP 1/4WR47K
FR204
ER-410380N
R FUSE VT05 RF25SCVTP 1/4WR91K [SEG]
FR205
ER-408829N
R FUSE VT05 RF25SCVTP 1/4WR11K
FR401
ER-418648N
R FUSE VT05 RF25SCVTP 1/4WR24K
FR402
ER-400729N
R FUSE VT05 RF25SCVTP 1/4WR47K
FR403
ER-418648N
R FUSE VT05 RF25SCVTP 1/4WR24K
F201
EF-394702N
FUSE 218 TIME 250V 2.00A
L201
EO-428349N
COIL LF UF1922C4-152Y1R5-01 [EXCEPT EA,EDG]
L202
EO-428417N1
COIL LF HF2022-333Y0R3-01
PH201
ET-422113N
PHOTO COUPLER P52561-1-V
P201
EJ-416590N
SOCKET INLET CCT-2302-0371 2P
R201
ER-422189N
R CT P BGR3N 3W 4R7K [EXCEPT EA,EDG]
FR201
ER-435803N
R FUSE VT05 RF25SVTP 1/4W 8R2J
FR202
ER-408829N
R FUSE VT05 RF25SCVTP 1/4WR11K
FR203
ER-400729N
R FUSE VT05 RF25SCVTP 1/4WR47K
FR204
ER-410380N
R FUSE VT05 RF25SCVTP 1/4WR91K [SEG]
FR205
ER-408829N
R FUSE VT05 RF25SCVTP 1/4WR11K
FR401
ER-418648N
R FUSE VT05 RF25SCVTP 1/4WR24K
FR402
ER-400729N
R FUSE VT05 RF25SCVTP 1/4WR47K
FR403
ER-418648N
R FUSE VT05 RF25SCVTP 1/4WR24K
F201
EF-394702N
FUSE 218 TIME 250V 2.00A
L201
EO-428349N
COIL LF UF 1922C4-152Y1R5-01 [EXCEPT EA,EDG]
L202
EO-428417N1
COIL LF HF2022-333Y0R3-01
PH201
ET-422113N
PHOTO COUPLER PS2561-1-V
P201
EJ-416590N
SOCKET INLET CCT-2302-0371 2P
R201
ER-422189N
R CT P BGR3N 3W 4R7K [EXCEPT EA,EDG]
T201
BT-435636N
TRANS POW V1252-M
10-A
EW-430842N
AC CORD 200S SF200 SF201 E [EXCEPT EA,SE,EK,EOH-N[S]
10-B
EW-425599N
AC CORD 200S CW2101CW4771 B S [EA,EOH-N[S]]
10-C
EW-436245N
AC CORD 200S SF628 SF201 B [SE,EK]
MULTI FUNCTION MENU MODE
This is an on-screen display of the various
modes you can programme via the TV screen.
LANGUAGE : To select a language for the on-
screen displays.
PS SET : To preset or cancel TV stations.
CLOCK SET : To set the clock and AUTO
ADJUST TV : station.
MODE : To set BSP (blank skip play ON/OFF),
OSD (on screen display ON/OFF), AV MUTE
(ON/OFF), 16:9 (REC ON/OFF, PB ON/OFF),
SCART2 (DECODER/ AV2), CM SKIP (30/60/
150/OFF), SYST. (colour system PAL
MESECAM/NTSC .PAL/NTSC 4.43), TV/
VCR, DIMMER (FLD bright-ness 1,2,3),AUTO
OFF (auto power off), SP/LP, THEATRE (ON/
OFF), I-HQ (ON/OFF), LOUDNESS (ON/OFF),
(repeat ON/OFF)
FEATURES: To perform
(return to counter
zoro), BLANK (blank search), INTRO (intro
scan) or T. TUNING (tape tuning) functions.
PROGRAM : To set manual timer recording.
PROGRAM LIST : To review the times, dates or
cancel programs that you have entered for timer
recording.
If necessary, refer to the respective sections in
the operator's manual for detailed information.
Some modes are not available on certain
models.
1. Press the "MENU" button on the remote
control unit. The menu list screen will be
displayed on the TV screen.
2. Select the desired menu with the "v" or "w"
button.
3. Press the "OK" button. The selected menu
screen will be displayed on the TV screen.
4. Select the desired mode (or function) with the
"w" or "v" button. The number of the modes
(or functions) depends on the sort of the
menu.
5. Set the each mode (or function) by pressing
the "w" or "v" button and ">" or "<" button.
6. Press the "OK" button. The selected menu
screen will be disappeared few seconds after
the "OK" button is pressed. This means the
setting has been completed correctly.
MANUAL TRACKING/PICTURE/STABILITY
ADJUSTMENT
Using the remote control, the VCR can be
adjusted for tracking and picture sharpness
anytime during the playback mode.
· Manual tracking control
Press the "<" or ">" button repeatedly until the
picture is clear. During manual tracking
adjustment, the tracking position is shown on
the TV screen, and disappears automatically
after adjustment has been completed. Use
this function when performing the A/C HEAD
phase adjustment.
· Picture sharpness control
Press the "v" button repeatedly to sharpen
the picture or press the "w" button to soften
the picture.
· Stability adjustment
1) To correct picture shake during the slow
motion or still mode: Press the "v" or "w"
button repeatedly until the picture shake is
corrected.
2) To correct tracking during the still mode:
Press the "<" or ">", button repeatedly until
the picture is clear
ERROR ANNOUNCEMENT
When a malfunction occurs, the following error
indicators appear on the FL display to indicate
the problem when the power is turned off.
Err 1 : AL power supply has short circuited.
Err 2 : The loading motor has stopped.
(When the mechanism position detect switch is
not able to read the specified code, that is to say
not able to reach the specified position within
the specified time.)
Err 3 : The drum motor has stopped. (When the
drum motor does not rotate due to condensa-
tion, etc.)
Err 4 : The capstan motor has stopped.
PRESETS IN THE TEST MODE
1) Engaging the "TEST MODE"
To set the VCR to the test mode, firstly short the
reset circuit pattern located on the bottom as
shown below, with a flat head screw driver (This
will ground the reset pin of the system
control MI-COM). Next, plug in the AC power
cord while pressing and holding both the
"STANDBY/ON" and "STOP/ EJECT" buttons
(on the FRONT PANEL) at the same time.
Short the reset circuit pattern to disengage the
"TEST MODE". (The test mode is not disen-
gaged, even if the AC power cord is discon-
nected, without shorting the reset circuit.
NOTE: Once the system control MI-COM is
reset, clock and program data will be cancelled.
2) Model code preset
1. Engage the "test mode". (Never turn the
power on.) The model code will be displayed
in the FL display in 8 digit form.
2. While pressing both the "FF" and "RWD"
buttons, reset the system control MI-COM and
keep holding the "FF" and "RWD" buttons until
the address number (typically, Fc or Fb)
appears. The address number will be shown
in 2 digits in the hours display of the FL
display and its data will be shown in 2 digits in
the minutes display.
3. Select address "Fc" by pressing the "FF" or
"FWD" button if the address "Fc" is not
appeared.
4. Choose the data in the address Fc column,
that corresponds to the model number you
are working on, from the following list. Set the
chosen data value by pressing the "STOP/
EJECT" or "PLAY" button.
(On the FL display, B, C and D are indicated
with small letters.)
5. Memorize the data into the EEP ROM IC by
pressing the "REC" button.
6. The address "Fd" and its data will be shown
in the FL display approx 2 seconds later
automatically. Repeat the presetting (steps 4
to 5) for addresses "Fd", "FE" and "FF" in the
same manner as address "Fc".
7. Reset the system control MI-COM to
disengage the model code preset mode.
NOTE : This model code preset is absolutely
necessary when the IC406 (EEP-ROM) on the
MAIN PCB is replaced.
3) Video switching point preset
1. Engage the "test mode" and press the
"POWER" button.
2. Connect CH-1 of an oscilloscope to VIDEO
OUT and CH-2 to the TP502 (V-SWP) on the
MAIN PCB for triggering.
3. Play back the reference tape TF-530RFS
(Part No. AT-751775). Check the channel
display of the FL display so that "1F" (center
position in the tracking range) is indicated at
this point. If not indicated, press the "<" or ">"
button on the remote control until "1F" is
indicated.
4. Press the "REC" button during playback.
5. Confirm that the switching point is positioned
6.5
± 0.3 H before the left edge of the V-sync
as shown.
Service Information
NOTE :
a) Make sure that the A/C head phase adjust-
ment has been adjusted correctly before
making video switching point preset. (Refer to
step 4-3)
b) This switching point preset is absolutely
necessary after the folllowing replacements.
· When the video head Assy is replaced.
· When the DRUM MOTOR PCB is replaced.
· When the SERVO/SYSCON MI-COM or EEP
ROM IC (IC406) on the MAIN PCB is
replaced.
4) Memorization of the reference RF enve-
lope detect voltage (l-HQ)
For correct operation of the I-HQ tape tuning
system, memorization of the reference RF
envelope detect voltage is absolutely necessary.
When the VIDEO HEAD Assy or EEPROM IC in
the MAIN PCB is replaced for any reason,
memorize the reference RF envelope detect
voltage according to the following procedure.
1. Engage the test mode.
2. Turn the VCR power ON.
3. Set the tape speed to "LP mode".
4. Insert the I-HQ test tape "TF-556AT" (AT-
751822J) and then perform tape tuning by
pressing both the "I-HQ" and "REC" buttons
simultenuously.
5. Make a recording on the I-HQ test tape for
more than minute and then rewind it to the
point where the recording was started.
6. Play back the tape. Reference RF envelope
detect voltage data in the memory is dis-
played in 2 digits in the minutes display part
of the FL display and the present envelope
detect voltage data is displayed in 2 digits in
the seconds display part (the data is dis-
played in hexadecimal numbers).
7. After the auto tracking has been activated,
press the "CANCEL" button on the remote
control unit. So present RF envelope detect
voltage data will be transferred to the minutes
part's 2 digits and memorized in the EEPROM
IC.
8. Next, set the tape speed to "SP mode" and
repeat the steps 4 to 7.
9. Terminate the test mode.
5) Other facilities in the test mode
1. Tracking position display
In the "SP play" mode, tracking position data
can be displayed on the FL display. Data is
displayed in 64 steps in hexadecimal numbers
from "00" to "3F" in the channel display part on
the FL display. Pressing the "TV/VCR" button on
the remote control unit during playback directly
sets the tracking to the maximum "3F" position
and pressing the "COUNTER RESET" button
sets it to the minimum "00" position.
Pressing the "PLAY" button during playback sets
tracking to the center position "iF" automatically.
If "IF" does not appear even when the "PLAY"
button is pressed, keep pressing the "<" or ">"
cursor button on the remote control until "1 F" is
indicated and then press the "OK" button to
memorize the position.
2. Suspension of the tape protection system
When the VCR is not in the "test mode", the
"REC PAUSE" mode will be released after 30
minutes in order to protect the tape. The "STILL"
mode will also be released after 5 minutes.
During the "test mode", however this tape
protection system will not operate.
Video head rotation will stop 5 mm. after the
"REC PAUSE" mode has been engaged even
during the test mode.


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2
AKAI VS-G760
Audio Diagram


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3
AKAI VS-G760
Front PCB Diagram
VIF Diagram (EDG)


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4
AKAI VS-G760
HiFi IF Diagram
VIF Diagram (SEG)


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5
AKAI VS-G760
Head Amp Diagram