Sony IFB-12 User manual

IFB-12 World
IFB-12 World
IFB-12A World
SIGNAL INTERFACE BOARD
J: S/N 030,001 to 031,450
U/C, AEP: S/N 040,001 to 041,750
J: S/N 031,451 and later
U/C, AEP: S/N 041,751 and later
SERVICE MANUAL
MODEL DEST.
............... .........

IFB-12/12A
!WARNING
This manual is intended for qualified service personnel only.
To reduce the risk of electric shock, fire or injuly, do not perform any servicing other than that
contained in the operating instructions unless you are qualified to do so. Refer all servicing to
qualified service personnel.
ATTENTION!!
AFIN D’EVITER TOUT RISQUE D’ÉLECTROCUTION
PROVENANT D’UN CHÂSSIS SOUS TENSION, UN
TRANSFORMATEUR D’ISOLEMENT DOIT ETRE UTILISÉ LORS
DE TOUT DÉPANNAGE.
LE CHÂSSIS DE CE RÉCEPTEUR EST DIRECTEMENT
RACCORDÉ Á L’ALIMENTATION SECTEUR.
ATTENTION AUX COMPOSANTS RELATIFS ÁLA
SÉCURITÉ!!
LES COMPOSANTS IDENTIFIÉS PAR UNE MARQUE !SUR
LES SCHÉMAS DE PRINCIPE, LES VUES EXPLOSÉES ET LES
LISTES DE PIECES SONT D’UNE IMPORTANCE CRITIQUE
POUR LA SÉCURITÉ DU FONCTIONNEMENT. NE LES
REMPLACER QUE PAR DES COMPOSANTS SONY DONT LE
NUMÉRO DE PIÉCE EST INDIQUÉ DANS LE PRÉSENT MANUEL
OU DANS LES SUPPLÉMENTS PUBLIÉS PAR SONY.
WARNING!!
AN INSULATED TRANSFORMER SHOULD BE USED DURING
ANY SERVICE TO AVOID POSSIBLE SHOCK HAZARD,
BECAUSE OF THE LIVE CHASSIS.
THE CHASSIS OF THIS RECEIVER IS DIRECTLY CONNECTED
TO THE AC POWER LINE.
SAFETY-RELATED COMPONENTWARNING!!
COMPONENTS IDENTIFIED BY A !!
!!
!MARK ONTHE SCHEMATIC
DIAGRAMS, EXPLODED VIEWS AND IN THE PARTS LIST ARE
CRITICAL TO SAFE OPERATION. REPLACE THESE COMPO-
NENTSWITH SONY PARTSWHOSE PART NUMBERS APPEAR
AS SHOWN IN THIS MANUAL OR IN SUPPLEMENTS PUB-
LISHED BY SONY.

IFB-12/12A
1. OPERATING INSTRUCTIONS
2. CIRCUIT DESCRIPTION
2-1. GENERAL ............................................................................................... 2-1(E)
2-2. POWER SUPPLY CIRCUIT .................................................................... 2-1(E)
2-3. INPUT MODE.......................................................................................... 2-1(E)
2-4. OUTPUT MODE...................................................................................... 2-2(E)
3. SEMICONDUCTORS
4. EXPLODED VIEWS
4-1. MAIN UNIT (IFB-12 (OLD))....................................................................... 4-1
4-2. MAIN UNIT (IFB-12 (NEW), IFB-12A) ..................................................... 4-2
5. ELECTRICAL PARTS LIST
6. BLOCK DIAGRAMS
7. DIAGRAMS
7-1. SCHEMATIC DIAGRAMS AND PRINTED WIRING BOARDS.............. 7-1
SCHEMATIC DIAGRAMS
• IFB-12 (OLD) (1/3) Board......................................................................... 7-5
• IFB-12 (OLD) (2/3) Board......................................................................... 7-6
• IFB-12 (OLD) (3/3) Board......................................................................... 7-7
• IFB-12 (NEW), IFB-12A (1/3) Board....................................................... 7-11
• IFB-12 (NEW), IFB-12A (2/3) Board....................................................... 7-12
• IFB-12 (NEW), IFB-12A (3/3) Board....................................................... 7-13
PRINTED WIRING BOARDS
• IFB-12 Board (OLD) .................................................................................. 7-4
• IFB-12 Board (NEW).................................................................................. 7-9
• IFB-12A Board.......................................................................................... 7-10
IFB-12 (OLD) : J: S/N 030,001 to 031,450
U/C, AEP: S/N 040,001 to 041,750
IFB-12 (NEW): J: S/N 031,451 and later
U/C, AEP: S/N 041,751 and later
TABLE OF CONTENTS
1(E)
()
()

1-1(E)
IFB-12/12A
1
SECTION 1
OPERATING INSTRUCTIONS This section is extracted
from operation manual.

1-2(E) IFB-12/12A
9
For the customers in the USA
This equipment has been tested and found to comply with the limits for
a Class B digital device, pursuant to Part 15 of the FCC Rules. These
limits are designed to provide reasonable protection against harmful
interference in a residential installation. This equipment generates,
uses, and can radiate radio frequency energy and, if not installed and
used in accordance with the instructios, may cause harmful
interference to radio communications. However, there is no guarantee
that interference will not occur in a particular installation. If this
equipment does cause harmful interference to radio or television
reception, which can be determined by turning the equipment off and
on, the user is encouraged to try to correct the interference by one or
more of the following measures:
– Reorient or relocate the receiving antenna.
– Increase the separation between the equipment and receiver.
– Connect the equipment into an outlet on a circuit different from that
to which the receiver is connected.
– Consult the dealer or an experienced radio/TV technician for help.
You are cautioned that any changes or modifications not expressly
approved in this manual could void your authority to operate this
equipment.
For the customers in Canada
This Class B digital apparatus complies with Canadian ICES-003.
English
WARNING
10
The IFB-12A signal interface board is a PC board to be mounted on
the projector or the signal interface switcher, etc. so that RGB and
audio signals from a computer, etc. can be input or output1) to a signal
interface switcher.
Location and Function of Parts
R/P R
G/Y
B/P
B SYNC/HD VD
L
R
AUDIO
(MONO)
123456
OUTIN
R-Y/VIDEO Y/Y
B-Y/C
ON
123 54
1IN/OUT (input/output) selector
By setting the IN/OUT selector, the BNC connectors 3function as
the input/output1) connectors.
2Indicator (red)
Lights up when the IFB-12A is selected or the IN/OUT selector is
set to OUT.
3Input/Output connector (BNC type)
When the IN/OUT selector is set to IN
Accepts RGB, component, HDTV2), S-VIDEO, VIDEO signals.1)
When the IN/OUT selector is set to OUT (Refer to the manual of
the equipment to be connected also.)
Output RGB, component and HDTV signals.1)
4AUDIO (L(MONO)/R) connectors (phono jack)
When the IN/OUT selector is set to IN
Connect to the AUDIO OUT connector on a VTR, etc. When
connecting a monaural audio source, connect it to L (MONO).
When the IN/OUT selector is set to OUT
Connect to the AUDIO IN connector of a monitor, etc.1)
1) Refer to the attached paper about the products on which the IFB-12A can be
mounted.
2) HDTV: 1125/60 interlaced HDTV Studio Standard.

1-3(E)
IFB-12/12A
11
5DIP switch
Set the position of the DIP switch according to the input signal.
(Refer to “Setting the DIP switch”.)
Mounting the IFB-12A
Note
Mounting or removal of signal interface boards must be performed by
qualified personnel only.
This section is for qualified service personnel only.
1 Loosen the screws completely and remove the panel.
2 Push in the IFB-12A along the rail.
3 Tighten the screws.
When removing the IFB-12A, loosen the screws completely and pull it
out.
12 3
Setting the Switches
Note
Be sure not to change the setting of the SW6, 7 and JP-3, 4, 5
connectors, as this may damage the equipment connected to this unit.
12
Rotary switch
Never change the
setting of the JP5
connector.
ON OFF MIX
RGB
JP1
JP1
JP5
JP5
JP2
JP2
75Ωterminate
switches 3, 4, 5 RGB/MIX switch
Setting the 75Ωterminate switches 3, 4, 5
Set the 75Ωterminate switches 3, 4, 5 to the appropriate position
according to how the computer and monitor are connected.
Normally set to the ON side.
Set to the OFF side when the IFB-12A is connected to a monitor and a
personal computer simultaneously.
Setting the RGB/MIX switch
Set the RGB/MIX switch to RGB when connecting the switcher to the
RGB input connectors on the monitor using the output board.
Set the RGB/MIX switch to MIX when connecting the switcher to the
projector.
If the Computer to be Connected Outputs
Monochrome Video Signal
Before connecting the computer, make sure that the IN/OUT selector of
the IFB-12A is set to IN side.
1 Connect the video output connector of the computer to the G/Y
connector of the IFB-12A.
2 Set the position of the JP-1, JP-2 connectors on the PC board.
The picture on the screen is displayed in monochrome.
Note
If step 2 is not performed, the picture on the screen is displayed in green.

1-4(E) IFB-12/12A
13
RG-59B/U up to 0.5 m up to 12 m up to 25 m up to 50 m
(3C-2V) cable
RG-6A/U up to 1 m up to 25 m up to 50 m up to 100 m
(5C-2V) cable
Position 1234
Setting the DIP Switch
Set the DIP switch to the appropriate position according to the input
signal.1)
Input mode can be selected
RGB signal input
Component signal
input
HDTV YPBPR
signal input
HDTV GBR signal
input
VIDEO signal input
S-VIDEO signal input
123456
ON
123456
ON
On Compensation Cable
Turn the rotary switch on the PC board (IFB-12A) to the appropriate
position according to the type and length of the BNC cables connecting
the MONITOR OUT connectors and a projector or monitor.
123456
ON
123456
ON
123456
ON
123456
ON
4
3
2
1
1) Refer to the attached paper about the products on which the IFB-12A can be
mounted.
14
Specifications
Input connectors
R/R-Y/PR/VIDEO connector (BNC type): Red signal input, 0.7 Vp-p ±2 dB,
75 ohms terminated
Component R-Y signal input, 0.7 Vp-p ±2 dB, 75 ohms terminated
HDTV PRsignal input, ±0.35 Vp-p ±2 dB, 75 ohms terminated
HDTV R signal input, composite 1 Vp-p ±2 dB, 75 ohms terminated
(Tri-level sync ±3 Vp-p, sync negative 0.3 Vp-p)
Non-composite 0.7 Vp-p ±2 dB, 75 ohms terminated
Composite video signal input, 1 Vp-p, 75 ohms terminated
G/Y /Y/Y connector (BNC type): Green signal input, 0.7 Vp-p ±2 dB, 75 ohms
terminated
Sync-on-green signal input, 1 Vp-p ±2 dB, 75 ohms terminated
Component Y signal input, 1 Vp-p ±2 dB, sync negative, 75 ohms
terminated
HDTV Y signal input, 1 Vp-p ±2 dB, 75 ohms terminated
(Tri-level sync ±3 Vp-p, sync negative 0.3 Vp-p)
HDTV G signal input, composite 1 Vp-p ±2 dB, 75 ohms terminated
(Tri-level sync ±3 Vp-p, sync negative 0.3 Vp-p)
Non-composite 0.7 Vp-p ±2 dB, 75 ohms terminated
S-VIDEO Y signal input, 1 Vp-p ±2 dB, 75 ohms terminated
B/B-Y/PB/C connector (BNC type): Blue signal input, 0.7 Vp-p ±2 dB, 75 ohms
terminated
Component B-Y signal input, 0.7 Vp-p ±2 dB, 75 ohms terminated
HDTV PBsignal input, ±0.35 Vp-p ±2 dB, 75 ohms terminated
HDTV B signal input, composite 1 Vp-p ±2 dB, 75 ohms terminated
(Tri-level sync ±3 Vp-p, sync negative 0.3 Vp-p)
Non-composite 0.7 Vp-p ±2 dB, 75 ohms terminated
S-VIDEO C signal input, 0.286 Vp-p ±2 dB, 75 ohms terminated (NTSC),
0.3 Vp-p ±2 dB, 75 ohms terminated (PAL)
SYNC/HD connector (BNC type): Composite sync signal, horizontal sync input,
0.6 to 8 Vp-p, high impedance, positive/netagive
HDTV tri-level sync signal input, ±0.3 Vp-p, sync negative, 0.3 Vp-p,
75 ohms terminated
VD connector (BNC type): Vertical sync signal input, 0.6 to 8 Vp-p, high
impedance, positive/negative
HDTV tri-level sync signal input, ±0.3 Vp-p, sync negative, 0.3 Vp-p, 75
ohms terminated
AUDIO connector (Phono jack): Audio signal input, 500 mVrms, impedance
47 kohms
Design and specifications are subject to change without notice.

2-1(E)
IFB-12/12A
SECTION 2
CIRCUIT DESCRIPTIONS
IFB-12 (OLD): J: S/N 030,001 to 031,450
U/C, AEP: S/N 040,001 to 041,750
IFB-12 (NEW): J: S/N 031,451 and later
U/C, AEP: S/N 041,751 and later
2-1. GENERAL
This board is a 5-BNC analog input/output board which is
able to serve as an input or output board using the IN/OUT
switch. The output board is equipped with a feed
compensation function for cable, and a compensation rate
can be selected with the compensation mode switch
according to the length of the coaxial cable.
2-2. POWER SUPPLY CIRCUIT
+12 V to +15 V power is supplied from the 96-pin
connector CN3 (A4, B4, and C4) (IFB-12 (OLD)), J1 (A4,
B4, and C4) (IFB-12 (NEW), IFB-12A) terminals. The IN/
OUT select switch is used to select the power for the input
or output circuit.
1When the IN/OUT switch is set to the IN side and CN3
(C19) (IFB-12 (OLD)), J1 (C19) (IFB-12 (NEW), IFB-
12A) becomes “LOW”, Q25 is turned OFF, Q28 is
turned ON, and relays RY1 to RY5 (IFB-12 (OLD)),
RL1 to RL5 (IFB-12 (NEW), IFB-12A) are turned ON
by IC25, and the power supply line is connected to the
input circuit as well as the LED lights up.
2When the IN/OUT switch is set to the OUT side and
RGB/VIDEO terminal CN3 (A17) (IFB-12 (OLD)), J1
Input mode
RGB
COMPONENT
HDTV Y Pr Pb
HDTV GBR
C VIDEO
S VIDEO
DIP SW
1
2
3
4
5
6
RGB/VIDEO
(A17)
H
M
H
H
L
L
VIDEO/YC
(C17)
H
H
L
H
H
L
CODE1
(B16)
H
H
L
L
H
H
Related
transistor
Q4
Q5, Q6
Q5
Q8
Q7, Q8
(A17) (IFB-12 (NEW), IFB-12A) becomes “MIDDLE”
or “HIGH” (+1.7 V to +5.2 V), Q25 is turned OFF,
Q28 is turned ON, and relays RY1 to RY5 (IFB-12
(OLD)), RL1 to RL5 (IFB-12 (NEW), IFB-12A) are
turned OFF by the comparator IC26 and IC25, the
power supply line is connected to the output circuit as
well as the LED lights up. When the RGB/VIDEO
terminal becomes “LOW” (input is a video signal), the
output circuit does not function.
3R208, Q22, Q23, and Q24 serve as a current detection
protector. When excessive current flows (higher than
1.2 A), Q22, Q23, and Q24 are turned ON, and Q28 is
turned OFF (power is shut off) as well as protector
terminal CN3 (A2) (IFB-12 (OLD)), J1 (A2) (IFB-12
(NEW), IFB-12A) is connected to GND, and failure is
indicated to the outside.
2-3. INPUT MODE
When the IN/OUT switch (S2: IFB-12 (OLD)), (SW2:
IFB-12 (NEW), IFB-12A) is set to the IN side and SEL
(C19) terminal becomes LOW, this mode is set.
11
11
1Input mode setting (Table 1)
When the DIP switch is turned ON according to the input
signal, RGB/VIDEO, VIDEO/YC, and CODE1 control
signals are passed through transistors Q2 to Q8 and output
to CN3 (A17, C17, and B16) (IFB-12 (OLD)), J1 (A17,
C17, and B16) (IFB-12 (NEW), IFB-12A) according to the
input mode. This informs external devices such as a
switcher, etc. of the input signal type.
Table 1
()
()

2-2(E) IFB-12/12A
22
22
2Video signal
Video signals input from the BNC terminal are passed
through relays RY1, 2, and 3 (IFB-12 (OLD)), RL1, 2, and
3 (IFB-12 (NEW), IFB-12A) and are input to +6 dB
amplifier ICs 19, 20, and 21. This input signals are usually
terminated with the 75 Zterminator switches S3, 4, and 5
(IFB-12 (OLD)), SW3, 4, and 5 (IFB-12 (NEW), IFB-
12A). When JP 1 and 2 connectors are set to the G-R and
G-B sides, only G signal is generated, and a black-and-
white image is output.
RGB signals input from ICs 19, 20, and 21 are passed
through RY7, 8, and 9 (IFB-12 (OLD)), RL7, 8, and 9
(IFB-12 (NEW), IFB-12A) and are output to CN3 (21, 25,
and 29) (IFB-12 (OLD)), J1 (21, 25, and 29) (IFB-12
(NEW), IFB-12A) terminals.
33
33
3SYNC signal
A 75 Zor 1 K Ztermination resistance can be selected for
SYNC/HD and VD signals input from the BNC terminal
using terminator switches S6 and 7 (IFB-12 (OLD)), SW6
and 7 (IFB-12 (NEW), IFB-12A).
Q10, Q11, and IC (1/2), and Q14, Q15, and IC (2/2), and
Q12, 27 (IFB-12 (NEW), IFB-12A) serve as a peak
detection circuit for SYNC/HD and VD signals. These
signals are compared with the intermediate value of the
peak value, are converted to TTL level SYNC signals by
IC3 and output to CN3 (12, 14) (IFB-12 (OLD)), J1 (12,
14) (IFB-12 (NEW), IFB-12A). Also with IFB-12 (NEW),
IFB-12A, when input signal is recognized as TTL level,
SYNC/HD, VD, which is input from BNC terminal, is
input to relay RL6 as it is, then it is output to J1 (12, 14) by
control of this relay. When the SYNC signals are used to
process signals synthesized with video signals, JP3 and 4
are set to the VIDEO side.
By switching JP5 to GS side, SYNC signals CS and VS are
input from IC2 for input signals such as SYNC ON
GREEN, Y signal, etc.
44
44
4Audio signal
AUDIO L and R signals input from the pin jack terminal
are input to the buffers Q16 and Q17, and are output to
CN3 (A7, A8) (IFB-12 (OLD)), J1 (A7, A8) (IFB-12
(NEW), IFB-12A) by the analog IC4 switch.
2-4. OUTPUT MODE
When the IN/OUT switch (S2: IFB-12 (OLD)), (SW2:
IFB-12 (NEW), IFB-12A) is set to the OUT side and RGB/
VIDEO signal level of CN3 (A17) (IFB-12 (OLD)), J1
(A17) (IFB-12 (NEW), IFB-12A) becomes MIDDLE or
HIGH, this mode is set. IN/OUT terminal of CN3 (B23)
(IFB-12 (OLD)), J1 (B23) (IFB-12 (NEW), IFB-12A)
becomes LOW and informs the outside of the output mode.
11
11
1Video signal
RGB signals input from CN3 (B3, B5, and B7) (IFB-12
(OLD)), J1 (B3, B5, and B7) (IFB-12 (NEW), IFB-12A)
are terminated with the 75 Ztermination resistors R50, 90,
and 130, and are passed through buffer ICs 7, 8, and 9 to
be distributed for four outputs. These signals become four
signals in which high-frequency is emphasized by R and C,
and cable compensation elements CR1, CR2, and CR3.
Analog switch ICs 10, 11, and 12 are used to select one
compensation rate required from these four signals
according to the mode S8 (IFB-12 (OLD)), SW8 (IFB-12
(NEW), IFB-12A). These signals are amplified by the 7
times output amplifier ICs 13, 14, and 15, are passed
through relay RY1, RY2, and RY3 (IFB-12 (OLD)), RL1,
RL2, and RL3 (IFB-12 (NEW), IFB-12A), and are output
to the BNC terminal. Q18, 19, 20, IC16, and IC17 serve as
corresponding feedback clamp circuits, detects black level
of output signals, and applies DC bias
to the output amplifier.
22
22
2SYNC signal
SYNC HS and VS signals input from CN3 (B8 and B10)
(IFB-12 (OLD)), J1 (B8 and B10) (IFB-12 (NEW), IFB-
12A) are passed through buffer IC5 (IFB-12 (OLD) only)
and relay RY4 (IFB-12 (OLD)), RL4 (IFB-12 (NEW),
IFB-12A) and are output to the BNC terminal.
33
33
3Audio signal
AUDIO L and R signals input from CN3 (B1 and B6)
(IFB-12 (OLD), J1 (B1 and B6) (IFB-12 (NEW), IFB-
12A) are passed through relays RY6 and RY5 (IFB-12
(OLD)), RL5 (IFB-12 (NEW), IFB-12A), and output to the
pin jack terminal.
44
44
4Others
When the NOR/MIX switch S12 (IFB-12 (OLD)), SW12
(IFB-12 (NEW), IFB-12A) on the board is switched to
NOR or MIX, “HIGH” or “LOW” voltage is output to
CN3 (B31) (IFB-12 (OLD)), J1 (B31) (IFB-12 (NEW),
IFB-12A) terminal. The signal type to be output (monitor
output or projector output) can be indicated to an external
switcher, etc.