Star Tech Journal
Issue: 1983-October - Vol 5 Issue 8 - Page 11
11
STAR.TECH JOURNAL/OCTOBER 1983
Troubleshooting Sega's Frogger continued.
simultaneously fed over to the main logic board and to IC40 (8255) to provide the addressing signals
for this Programmable Peripheral Interface (PRI). The sound board contains an independent
14.318MHz crystal. This clock circuit is inverted and amplified by IC14 and fed over to IC6. The
outputs ofIC6 are simultaneously sent to IC5, 26, and 35 to provide the main clock, and to IC15.
IC15, 16, and 17 divide the clock signal to provide 4 secondary timing signals to IC35, the sound
operator. The Z-80 (IC26) is exercised by the signal" SINT" which comes in at pin 16 from IC40 via
ICs 39 and 11. The Z-80 (IC26) addresses the sound EPROMs, IC32, 33 and 34 and sound RAMs
IC30, 31. The outputs of the EPROMs and RAMs ( data) are sent over to the Z-80 (IC26) and to the
sound generator, IC35. The outputs of the sound generator, CHAI, CHBI, andCHCl (pins 4, 3, and
38), under control ofIC40 and 36, are sent to the output stage, ICI. ICI acts as an output amplifier.
The signal OP AMP (OUTPUT) is also fed over to a group of independent switches, ICs 22, 18, 23,
19, 20 and 24. These switches are used to provide the different tunes for the game.
NOTE: This article was written using the electronics 834-0068 as a reference. Although the
article was written for 834-0068, the theory can also be applied to the 834-0222 ASSY, and Moon
Cresta type logic board. The major difference will be in the IC identification.
*
SEGA
*
SERVICE NOTES
ELECTROHOME COLOR X-Y MONITOR DEFLECTION AMP MOD
G-80 POWER SUPPLY CONNECTOR MOD
PENGO EPROM LOCK UP
*
*
Electrohome Color X·Y Monitor Deflectlon Amp Mod
Game/AssemblyAJJected: 19" Color X-Y Monitor (PIN 200-0025-00)
E/H G08-003
Subject: Deflection Amp PCB; R635 equivalent
Action: A single 3-ohrn 20-watt resistor (PIN 474-0003-00) may be used interchangeably with the
existingpair ofl .5-ohrn resistors (PIN 474-0150-00) in the event of a failure. The G08-003 Color X-
y Monitor was used in the following games: Space Fury, Eliminator, Zektor, Tac/Scan, Star Trek.
G-80 Power Supply Connector Mod
Game/Assembly AjJected.· G-80 Power Supply (PIN 800-0191)
Subject: Molex P4 of the G-80 Power Supply PC (PIN 800-0170)
Action: It has been noted that in some instances where the modification to strap pins 4 and 6 of P4
together was not accomplished before a failure occurred, carbonization of these pins has seriously
impeded performance. Therefore, Sega recommends that you inspect P4 to verify its good condition
(as well as its mating connector pins), and ifin doubt, simply scrape the offending pins of carbon and
re-tin using a rosin-core solder. In the case of fouled connector crimp-pins, it is much easier to simply
replace them (PIN 211-0005-00).
Pengo EPROM Lock-Up
Game/Assembly AjJected.· Pengo
Subject: Apparent inability of the Sno-Bee character to move from the screen corners
Action: Unplug the game; remove and replace the game EPROMs, taking care to ensure that the IC
pins are not bent during reinstallation. If the Sno-Bees remain inanimate, call Sega Customer Service
Technical Assistance.
*
ATARI
Got a downed video arcade
game? RCA SK semiconductors
get it back into action fast.
Available at over 500 RCA SK
Distributors. For the one near-
est you, call (609) 853-2229, or
mail in the coupon.
Replace components in:
• Atari
• Gottlieb
• Bally
• Gremlin
• Cinema-
• Midway
tronics
• Stern
• Exidy
• Williams
Get your free copy of RCA's
SK Video Arcade Game
Cross Reference for fast
identification of correct
replacements.
Just send in
this coupon.
You will also
receive a list
of RCA SK
Distributor
locations.
Please send me my FREE copy
of the RCA SK Video Arcade
Game Cross Reference 1 K7235.
RCA Distributor
& Special Products Division
Sales Promotion Services
2000 Clements Bridge Road
Deptford, NJ 08096
Name
Company
Street
STAR WARS UNRELIABLE POWER-UP
City
By Howard M. Smith, B&B Vending, Dallas, TX
State
In repairing Atari Star Wars' boards on the PAT 9000 test fixture, we have noticed that quite a few of
them will not power up reliably. This does not appear to be a very common problem when the boards
are installed in a game, but we have seen it enough to report it as a valid problem.
The problem lies in the crystal oscillator circuit on the main printed circuit board. Atari is
installing a 68-ohrn resistor at R3 instead of the 220-ohrn value specified on the schematic. I am sure
they had a good reason to make this change, but the problem bas disappeared in every board that we
changed R3 back to the original value of 220 ohms.
When troubleshooting this problem, one should not be fooled by the presence of the oscillator
signal. The signal is present, but is not at the correct frequency.
ROIi
Zip
Distributor and
Special Products Division
STAR.TECH JOURNAL/OCTOBER 1983
Troubleshooting Sega's Frogger continued.
simultaneously fed over to the main logic board and to IC40 (8255) to provide the addressing signals
for this Programmable Peripheral Interface (PRI). The sound board contains an independent
14.318MHz crystal. This clock circuit is inverted and amplified by IC14 and fed over to IC6. The
outputs ofIC6 are simultaneously sent to IC5, 26, and 35 to provide the main clock, and to IC15.
IC15, 16, and 17 divide the clock signal to provide 4 secondary timing signals to IC35, the sound
operator. The Z-80 (IC26) is exercised by the signal" SINT" which comes in at pin 16 from IC40 via
ICs 39 and 11. The Z-80 (IC26) addresses the sound EPROMs, IC32, 33 and 34 and sound RAMs
IC30, 31. The outputs of the EPROMs and RAMs ( data) are sent over to the Z-80 (IC26) and to the
sound generator, IC35. The outputs of the sound generator, CHAI, CHBI, andCHCl (pins 4, 3, and
38), under control ofIC40 and 36, are sent to the output stage, ICI. ICI acts as an output amplifier.
The signal OP AMP (OUTPUT) is also fed over to a group of independent switches, ICs 22, 18, 23,
19, 20 and 24. These switches are used to provide the different tunes for the game.
NOTE: This article was written using the electronics 834-0068 as a reference. Although the
article was written for 834-0068, the theory can also be applied to the 834-0222 ASSY, and Moon
Cresta type logic board. The major difference will be in the IC identification.
*
SEGA
*
SERVICE NOTES
ELECTROHOME COLOR X-Y MONITOR DEFLECTION AMP MOD
G-80 POWER SUPPLY CONNECTOR MOD
PENGO EPROM LOCK UP
*
*
Electrohome Color X·Y Monitor Deflectlon Amp Mod
Game/AssemblyAJJected: 19" Color X-Y Monitor (PIN 200-0025-00)
E/H G08-003
Subject: Deflection Amp PCB; R635 equivalent
Action: A single 3-ohrn 20-watt resistor (PIN 474-0003-00) may be used interchangeably with the
existingpair ofl .5-ohrn resistors (PIN 474-0150-00) in the event of a failure. The G08-003 Color X-
y Monitor was used in the following games: Space Fury, Eliminator, Zektor, Tac/Scan, Star Trek.
G-80 Power Supply Connector Mod
Game/Assembly AjJected.· G-80 Power Supply (PIN 800-0191)
Subject: Molex P4 of the G-80 Power Supply PC (PIN 800-0170)
Action: It has been noted that in some instances where the modification to strap pins 4 and 6 of P4
together was not accomplished before a failure occurred, carbonization of these pins has seriously
impeded performance. Therefore, Sega recommends that you inspect P4 to verify its good condition
(as well as its mating connector pins), and ifin doubt, simply scrape the offending pins of carbon and
re-tin using a rosin-core solder. In the case of fouled connector crimp-pins, it is much easier to simply
replace them (PIN 211-0005-00).
Pengo EPROM Lock-Up
Game/Assembly AjJected.· Pengo
Subject: Apparent inability of the Sno-Bee character to move from the screen corners
Action: Unplug the game; remove and replace the game EPROMs, taking care to ensure that the IC
pins are not bent during reinstallation. If the Sno-Bees remain inanimate, call Sega Customer Service
Technical Assistance.
*
ATARI
Got a downed video arcade
game? RCA SK semiconductors
get it back into action fast.
Available at over 500 RCA SK
Distributors. For the one near-
est you, call (609) 853-2229, or
mail in the coupon.
Replace components in:
• Atari
• Gottlieb
• Bally
• Gremlin
• Cinema-
• Midway
tronics
• Stern
• Exidy
• Williams
Get your free copy of RCA's
SK Video Arcade Game
Cross Reference for fast
identification of correct
replacements.
Just send in
this coupon.
You will also
receive a list
of RCA SK
Distributor
locations.
Please send me my FREE copy
of the RCA SK Video Arcade
Game Cross Reference 1 K7235.
RCA Distributor
& Special Products Division
Sales Promotion Services
2000 Clements Bridge Road
Deptford, NJ 08096
Name
Company
Street
STAR WARS UNRELIABLE POWER-UP
City
By Howard M. Smith, B&B Vending, Dallas, TX
State
In repairing Atari Star Wars' boards on the PAT 9000 test fixture, we have noticed that quite a few of
them will not power up reliably. This does not appear to be a very common problem when the boards
are installed in a game, but we have seen it enough to report it as a valid problem.
The problem lies in the crystal oscillator circuit on the main printed circuit board. Atari is
installing a 68-ohrn resistor at R3 instead of the 220-ohrn value specified on the schematic. I am sure
they had a good reason to make this change, but the problem bas disappeared in every board that we
changed R3 back to the original value of 220 ohms.
When troubleshooting this problem, one should not be fooled by the presence of the oscillator
signal. The signal is present, but is not at the correct frequency.
ROIi
Zip
Distributor and
Special Products Division
Future scanning projects are planned by the International Arcade Museum Library (IAML).