Star Tech Journal
Issue: 1983-September - Vol 5 Issue 7 - Page 14
14
STAR*TECH JOURNAL/SEPTEMBER 1983
New System Preview continued.
•5. Set chroma input level (Rl44) fully clockwise, then rotate slowly counter-
clockwise until color appears, then rotate counter-clockwise ano~er 30°-
400_
6. Connect scope at 1 Ou sec/ div (AC couple) to blue output (P 103-6). Adjust
..,
0
.., ;,;
..,
N
)(
1l
E
cs,>,
-,Cl)
Screw, Mach. Pn Hd, No. 6-32 x 2.00
Washer, Lock, No. 6 Int
25-10571-01
\
PCA Main Board
81-12035-01
,-6
I
(4)
Nut Hex, No. 6-32
25-10557-01 (4)
Ribbon Cable Assy.
87-12093-01
/
Plate, Circuit Mtg
7. With scope at blue output, adjust sul>-brilliance (Rl 30) and contrast pro-
set (Rl 06) for a black level of0.5 volts and a peak white level of 4.0 volts
respectively .
8 . With scope at blue output, adjust sul>-color (Rl 39) so that the peak level
for the grey bar and the peak level for the blue bar are equal.
9. Connect the scope to the green output (P103-5) and adjust the sul>-tint so
that the peak level for the cyan bar and the peak level for the green bar are
equal.
Figure 3·B
25-11756-01 (4)
Ll0l (3.58MHz trap) for minimum of 3.58 MHz carrier riding on video
signal.
10. If necessary, readjust the contrast pro-set(Rl06) for a peak white level of
4.0 volts (3.5v above black level).
•Chroma input level control (Rl44) should not require any field adjustment
However, should the condition occur when no color is obtained at any position
of Rl 39 with all external controls disconnected, the following procedure may
be used
20-12092-01
1. Perform field set-up procedure steps 1 through 5.
\,,
~~
'
PCA ROM
81-12056-01
•
'
.
-~
/
/
Spacer, Nylon, No. 6-1.00
25-11753-02 (4)
/
Screw. Mach. Pn Hd, No. 6-32 x 1 ¼
Figure 3 .c
25-10571-01 (4)
Nut Hex No. 6-32
25-10557-01 (4)
25-11756-01 (4)
Washer, Lock, No. 6 Int
Spacer, Nylon, No. 6 x 'Ml
25-11753-01 (8)
The ROM board is carried piggyback on the PCA CPU board and is one of the
components changed when the unit is changed, or converted to a new game.
Monitor
2. Adjust color control (Rl 39) to the center of its range.
3. Turn chroma input level control (Rl44) to MAX CW position.
4. Turn Rl44 CCW until color just comes into picture. Now rotate Rl 44, 10-
15 degrees CCW.
5. Adjust color control (Rl39) for best color and tint control (Rl36) for
proper tint.
The Electrohome NTSC Decoder Board is designed to provide high quality
video information for display on a standard RGB Monitor. This board takes the
NTSC Output from any video system, i.e., VHS or Beta VCR, video disc, color
or B&W camera, DBS receiver, or personal computer) and provides the RGB
drive signal plus a sync signal for RGB Monitors such as the Electrohome G07
series.
The monitor is a standard Electrohome monitor that has had a decoder board
added to it in order to convert the television signal coming from the disc player
into a signal that can be used by the monitor. The board that has been added is
known as an NTSC Decoder Board and is manufactured by Electrohome. The Electrohome NTSC Decoder Board Specifications
service manual for the monitor,just like the service manual for the game, has not
been completed yet If any servicing is necessary for the monitor, it may be done General Description: The NTSC Decoder Board enables the display of
using a standard Electrohome monitor service manual. The horizontal and NTSC composite color video on any standard RGB Monitor.
vertical sync circuitry are adjusted normally and these instructions are attached Input Impedance: lVP-P ± 10 dB (300mV-3 V P-P)
to the monitor.
The NTSC Decoder Board has several pots for adjustment and I'll give Bandwidth: 6.3MHz
these to you now.
*Power Requirements: 16vdc 50mA (lOOmV ripple max)
Rl 07 is the white drive (this is a very sensitive adjustment).
Video Outputs: Separate R, G, B, and sync outputs
Rl 06 is contrast
Signal Level: White-3.5v ± 0.5v
Rl44 is the color cut-off. (This should be kept fully counter-clockwise.)
(RGB)
Black-0.5v
Rl 3 9 is the tint.
Rise Time: 0 .5 usec Typical
Rl 30 is brightness.
SIN Radio:> 35 dB (reference white lv)
Rl 36 is the hue.
Output Impedance (RGB): 270 ohm
The NTSC board has a specialty IC on it If this board goes bad, simply
Sync: Positive Composite
replace it To align a new control panel or an after market controller, you must
Sync Level: High-4.0v ± l .0v
do the following:
Low-0.5v + 0.2v
NTSC Decoder Board Alignment Procedure
Preliminary:
1. If customer supplied external controls are ~ing used, connect them to P 102
and set all controls to mechanical center. Leave these controls set to center
for the duration of the alignment procedure.
2. Set all six PCB controls to mechanical center except the sul>-contrast
(Rl07) which is set to the full clockwise position.
Set Up:
1. Connect a composite video color bar signal at l .0v pp to the PCB input at
PlOl.
2. Adjust sul>-contrast (Rl07) for maximum contrast with no overdrive.
Overdrive appears as vertical white bars between the color bars, most
noticeable between the yellow and cyan bars.
3. Adjust sul>-brillance (Rl 30) until the black portion of the color bar pattern
just turns black ( raster just extinguished).
4. Critically adjust trimmer capacitor Cl24 to center of color lock-in range. It
is a good idea to power PCB/monitor off for a few seconds, then back on to
ensure color lock.
**Horizontal Resolutlon: 500 lines
Defined as: The number of distinct vertical lines, alternately black and white,
which can be seen in a distance equal to the picture height
Vertical Resolution: 500 lines min.
Defined as: The number of horizontal scanning lines that can be seen on the
screen. Vertical resolution is limited to the number of horizontal lines per frame.
(NTSC system maximum is 525 lines.)
Controls: On board Contrast, Color, Brilliance, White Level, and Tint
External Controls: Provision is made for external Detai~ Color, and Tint
controls for special application purposes. The Detail control allows for reduced
horizontal resolution in low SIN ratio applications.
Connectors: All connectors are standard 0.156" Molex.
NOTE: BNC, RCA, and F-type connectors are available for input connection
on special order.
•t 6v may be obtained on Electrohome G07 monitor by adding a wire from Pin
102-1 on NTSC Board to the cathode of D504 on the G07 chassis .
.. Spec referenced to a Philips PM5519 video generator as a signal source and
an Electrohome G07 19" monitor.
Continued on next page.
STAR*TECH JOURNAL/SEPTEMBER 1983
New System Preview continued.
•5. Set chroma input level (Rl44) fully clockwise, then rotate slowly counter-
clockwise until color appears, then rotate counter-clockwise ano~er 30°-
400_
6. Connect scope at 1 Ou sec/ div (AC couple) to blue output (P 103-6). Adjust
..,
0
.., ;,;
..,
N
)(
1l
E
cs,>,
-,Cl)
Screw, Mach. Pn Hd, No. 6-32 x 2.00
Washer, Lock, No. 6 Int
25-10571-01
\
PCA Main Board
81-12035-01
,-6
I
(4)
Nut Hex, No. 6-32
25-10557-01 (4)
Ribbon Cable Assy.
87-12093-01
/
Plate, Circuit Mtg
7. With scope at blue output, adjust sul>-brilliance (Rl 30) and contrast pro-
set (Rl 06) for a black level of0.5 volts and a peak white level of 4.0 volts
respectively .
8 . With scope at blue output, adjust sul>-color (Rl 39) so that the peak level
for the grey bar and the peak level for the blue bar are equal.
9. Connect the scope to the green output (P103-5) and adjust the sul>-tint so
that the peak level for the cyan bar and the peak level for the green bar are
equal.
Figure 3·B
25-11756-01 (4)
Ll0l (3.58MHz trap) for minimum of 3.58 MHz carrier riding on video
signal.
10. If necessary, readjust the contrast pro-set(Rl06) for a peak white level of
4.0 volts (3.5v above black level).
•Chroma input level control (Rl44) should not require any field adjustment
However, should the condition occur when no color is obtained at any position
of Rl 39 with all external controls disconnected, the following procedure may
be used
20-12092-01
1. Perform field set-up procedure steps 1 through 5.
\,,
~~
'
PCA ROM
81-12056-01
•
'
.
-~
/
/
Spacer, Nylon, No. 6-1.00
25-11753-02 (4)
/
Screw. Mach. Pn Hd, No. 6-32 x 1 ¼
Figure 3 .c
25-10571-01 (4)
Nut Hex No. 6-32
25-10557-01 (4)
25-11756-01 (4)
Washer, Lock, No. 6 Int
Spacer, Nylon, No. 6 x 'Ml
25-11753-01 (8)
The ROM board is carried piggyback on the PCA CPU board and is one of the
components changed when the unit is changed, or converted to a new game.
Monitor
2. Adjust color control (Rl 39) to the center of its range.
3. Turn chroma input level control (Rl44) to MAX CW position.
4. Turn Rl44 CCW until color just comes into picture. Now rotate Rl 44, 10-
15 degrees CCW.
5. Adjust color control (Rl39) for best color and tint control (Rl36) for
proper tint.
The Electrohome NTSC Decoder Board is designed to provide high quality
video information for display on a standard RGB Monitor. This board takes the
NTSC Output from any video system, i.e., VHS or Beta VCR, video disc, color
or B&W camera, DBS receiver, or personal computer) and provides the RGB
drive signal plus a sync signal for RGB Monitors such as the Electrohome G07
series.
The monitor is a standard Electrohome monitor that has had a decoder board
added to it in order to convert the television signal coming from the disc player
into a signal that can be used by the monitor. The board that has been added is
known as an NTSC Decoder Board and is manufactured by Electrohome. The Electrohome NTSC Decoder Board Specifications
service manual for the monitor,just like the service manual for the game, has not
been completed yet If any servicing is necessary for the monitor, it may be done General Description: The NTSC Decoder Board enables the display of
using a standard Electrohome monitor service manual. The horizontal and NTSC composite color video on any standard RGB Monitor.
vertical sync circuitry are adjusted normally and these instructions are attached Input Impedance: lVP-P ± 10 dB (300mV-3 V P-P)
to the monitor.
The NTSC Decoder Board has several pots for adjustment and I'll give Bandwidth: 6.3MHz
these to you now.
*Power Requirements: 16vdc 50mA (lOOmV ripple max)
Rl 07 is the white drive (this is a very sensitive adjustment).
Video Outputs: Separate R, G, B, and sync outputs
Rl 06 is contrast
Signal Level: White-3.5v ± 0.5v
Rl44 is the color cut-off. (This should be kept fully counter-clockwise.)
(RGB)
Black-0.5v
Rl 3 9 is the tint.
Rise Time: 0 .5 usec Typical
Rl 30 is brightness.
SIN Radio:> 35 dB (reference white lv)
Rl 36 is the hue.
Output Impedance (RGB): 270 ohm
The NTSC board has a specialty IC on it If this board goes bad, simply
Sync: Positive Composite
replace it To align a new control panel or an after market controller, you must
Sync Level: High-4.0v ± l .0v
do the following:
Low-0.5v + 0.2v
NTSC Decoder Board Alignment Procedure
Preliminary:
1. If customer supplied external controls are ~ing used, connect them to P 102
and set all controls to mechanical center. Leave these controls set to center
for the duration of the alignment procedure.
2. Set all six PCB controls to mechanical center except the sul>-contrast
(Rl07) which is set to the full clockwise position.
Set Up:
1. Connect a composite video color bar signal at l .0v pp to the PCB input at
PlOl.
2. Adjust sul>-contrast (Rl07) for maximum contrast with no overdrive.
Overdrive appears as vertical white bars between the color bars, most
noticeable between the yellow and cyan bars.
3. Adjust sul>-brillance (Rl 30) until the black portion of the color bar pattern
just turns black ( raster just extinguished).
4. Critically adjust trimmer capacitor Cl24 to center of color lock-in range. It
is a good idea to power PCB/monitor off for a few seconds, then back on to
ensure color lock.
**Horizontal Resolutlon: 500 lines
Defined as: The number of distinct vertical lines, alternately black and white,
which can be seen in a distance equal to the picture height
Vertical Resolution: 500 lines min.
Defined as: The number of horizontal scanning lines that can be seen on the
screen. Vertical resolution is limited to the number of horizontal lines per frame.
(NTSC system maximum is 525 lines.)
Controls: On board Contrast, Color, Brilliance, White Level, and Tint
External Controls: Provision is made for external Detai~ Color, and Tint
controls for special application purposes. The Detail control allows for reduced
horizontal resolution in low SIN ratio applications.
Connectors: All connectors are standard 0.156" Molex.
NOTE: BNC, RCA, and F-type connectors are available for input connection
on special order.
•t 6v may be obtained on Electrohome G07 monitor by adding a wire from Pin
102-1 on NTSC Board to the cathode of D504 on the G07 chassis .
.. Spec referenced to a Philips PM5519 video generator as a signal source and
an Electrohome G07 19" monitor.
Continued on next page.
Future scanning projects are planned by the International Arcade Museum Library (IAML).