New Life Games LLC
NLG Users Repair Logs and Other Ramblings. Request your very own topic. Just ask any site staff. => Channelmaniac's Arcadecomponents' Old School Repair Logs => Topic started by: channelmaniac on May 07, 2014, 08:16:17 PM
-
Fixed: Shinobi
Symptom: Garbage on screen.
Found and repaired 2 cut/gouged traces and repaired bad hack solder job on the Yamaha DAC and LM324 audio op-amp.
Board was intermittently working and would stop/start working as the board was tapped or flexed. Narrowed it down to the CPU crystal oscillator. If you put pressure down on it the game would boot. Replaced the bad crystal oscillator and installed 2 missing NEC2501 ICs to finish the repair.
-
Fixed: Shinobi
Symptom: Dead
Replaced 6 broken RFI filters on player 1 inputs. A couple were easy to spot as they were crushed. The others were found with a mulitmeter when running a continuity test.
Burned new unencrypted audio ROM chip from the MAME ROM set and replaced the encrypted sound CPU with a standard Z80B CPU to finish the repair.
-
Fixed: Golden Axe
Symptom: Garbled/Missing Background Graphics
Swapped out the broken socket on IC21 with spare socket from empty IC23. Reset jumpers S1-S6 for proper ROM types on daughter board. Fixed a bent pin on the custom encrypted CPU to finish the repair.
-
Game: Shinobi
Symptom: Dead
Game was totally dead. Game had NO custom CPU on it and no activity on the ROMs and the CPU HALT* like was held low, indicating a bus problem.
Checked the chips with the WCF (well calibrated finger) and found every ROM was getting hot and the CPU even hotter. Checked the ROMs in the EPROM programmer and found that all were bad. Burned new EPROMs from the Shinobi3 MAME set for all but the sound ROMs and burned the sound ROMs from the Shinobi2 MAME set. (Shinobi3 had encrypted sound and Shinobi2 had encrypted program ROMs)
Replaced the CPU and the board would then boot but had no sound. Checked the reset line on the Z80B CPU. It checked good. Checked the clock line and found it was missing. Replaced the crystal oscillator and then had a clock signal but not at the CPU. Replaced the 74HC74 clock divider IC and had clock on the Z80B CPU but still no sound.
Replaced the sound RAM to get the sound working and to finish the game.
The only thing I could think of was a power spike or (more likely) someone hooked up power backwards.
-
Game: Shinobi
Symptom: Garbled graphics
Board took a hit on the corner where the PCB Foot is screwed down through the board. There are several traces that run through that area.
Repaired 2 damaged traces on the bottom of the board and 1 on the top then tested. The traces on the top board in that area carry sound data, the bottom connects to the video subsystem.
There are 8 traces on the top of the board but only the outer most of these was damaged. The rest were OK. However, these are LONG traces that go all the way around the outside of the board and are prone to damage. Here they are from the outside of the board inward - just in case it's needed for later.
E20, Pin 14 to CN4, pin A12
E20, Pin 13 to CN4, pin B12
E20, Pin 18 to CN4, pin A11
E20, Pin 17 to CN4, pin B11
E20, Pin 7 to CN4, pin A10
E20, Pin 8 to CN4, pin B10
E20, Pin 3 to CN4, pin A9
E20, Pin 4 to CN4, pin B9
-
Model: Golden Axe
Symptom: Graphic corruption
Game had garbled graphics that would get better if the ROMs on the daughterboard were reseated, then come back later. Resoldered IC3 on the bottom of the daughterboard and tested.
-
Model: Shinobi
Symptom: Dead
Repaired a broken trace on pin 10 of the CPU and tested. Repaired a broken trace to fix a graphics corruption problem. Replaced the dead custom sound CPU with a Z80B and reprogrammed the EPROM at location A7 with suicide-free code to finish the repair. Tested.
-
Model: Altered Beast
Symptom: No sound
Replaced suicided encrypted CPU with a Z80B and replaced the sound CPU's program ROM. Tested.
-
Model: Altered Beast
Symptom: No sound
Board had already had the encrypted CPU and Sound Program ROM replaced. The Z80 CPU used to replace the encrypted CPU was bad. Replaced CPU and tested.
-
Model: Altered Beast
Symptom: Corrupt Sound
Sound was garbled periodically. Recapped the audio section and replaced the audio amp. Still garbled. Noticed the garbled sound was at the same place every time. Replaced the suicide sound processor with a Z80B and installed a new sound program ROM. Tested game.
It appears that these suicide custom CPUs can partially fail and not properly play all sounds.
-
Model: Altered Beast
Symptom: Dead
Cleaned edge connector. Cleaned corroded pin 1 on the 68K CPU. Tested.
-
Model: Altered Beast
Symptom: Corrupt Graphics, no sound, and will not coin up.
Replaced 4 missing caps on the ROM board. Replaced 4 caps in the audio section and a bad 7759 sound IC to fix the sound issues. Replaced 2 missing graphics ROMs and 1 bad SRAM IC to fix the graphics problems. Board ran but would not coin up because it was missing the 8751 security chip. Replaced the Program ROMs with ones programmed with suicide free code for a different revision of the game. Board would coin up and play games but enemy characters were corrupt. Replaced the GFX ROMs with ones programmed with code from the altbeast5.zip MAME dumps. Tested successfully.
-
Model: Golden Axe
Symptom: Dead
Board had attempted repairs/mods done to it. Missing Z80C CPU.
Board smoked upon power up. Someone soldered or closed almost every jumper on the B board creating a short between +5 and ground. Removed solder from jumpers S1, S6, S7, S9, S11, and S19. Removed shorting blocks from jumpers S3, S14, S16, and S18. Verified trace connectivity on the B board.
Repaired one gouged trace on the bottom board, installed missing Z80C CPU, and tested. The board would not boot and there was no activity on the chip enable pins of the program ROMs. Replaced shorted 315-5195 custom system controller IC and repaired a burnt trace under it. Replaced 4 missing caps on the B board and 4 broken caps on the A board. Tested.
-
Model: Golden Axe
Symptom: Dead
Board wouldn't power up. LED was dead.
Cleaned edge connector with a fiberglass pencil. Board powered up but was still dead. Replaced suicide CPU module with a standard 68000 CPU and replaced the 2 program ROMs with suicide free code. Board would play but had low, scratchy audio. Replaced the electrolytic capacitors around the audio amp chip to restore audio levels and clarity. Board played but had a line in some of the characters. Replaced a bad 2018 SRAM at location 4G on the board. Tested.
-
Model: Shinobi
Symptom: No inputs and no sound
Board had attempted repairs. It had a CAT28C256 EEPROM installed at A6, no ROM at A7, and an incorrect speed rated Z80A CPU.
Cleaned edge connector to restore inputs. Replaced sound program ROM and installed it at the correct location A7 with the correct 27C256-20 EPROM and tested. Replaced Z80A CPU with the correct Z80B CPU and retested.
-
Model: Golden Axe
Symptom: Dead.
Suicide battery and the top cover were missing from the custom CPU.
Replaced the 2 program ROMs with 2 programmed with suicide free code. Replaced the custom CPU with a standard 68000 chip and tested. Sound was garbled until it warmed up. Replaced 2 470uf and 1 220uf capacitors in the sound section. Retested.
-
Model: Shinobi
Symptom: Dead
(Shinobi and Golden Axe came as a pair in an auction lot... someone had swapped chips around on them)
Removed an unnecessary 8751 protection CPU from the boardset. Replaced the custom sound CPU with a Z80 and reprogrammed ROM A7 with suicide free code. Tested and saw that the text elements were distorted. Pried up a filter capacitor from the ROM board connector pins as it was shorting out some pins. Replaced the 4 battered filter caps on the ROM board and successfully tested the game.
-
Model: Golden Axe
Symptom: Dead
(Shinobi and Golden Axe came as a pair in an auction lot... someone had swapped chips around on them)
Installed missing 8751 protection CPU, patched a gouged trace on the bottom of the board, and tested. Board would intermittently boot and crash at random. Checked the crystal oscillators as those are failure prone on Sega System 16 and 18 boardsets, but they were OK. Game would play if the 68K CPU was pushed downward. Removed CPU from its socket and found pin 1 wrapped under it. Straightened out the pin, reinserted the CPU, and successfully tested the game. Replaced the 4 mangled filter caps on the ROM board and retested.
-
Model: E-SWAT
Symptom: Dead
Checked multiple scraped traces on the bottom of the board. Replaced 2 program ROMs with suicide free code and replaced the custom CPU module with a 68000 CPU. Tested.
-
Model: E-SWAT
Symptom: Dead
Replaced 2 program ROMs with suicide free code and replaced the custom CPU module with a 68000 CPU. Tested.
-
Model: Quartet 2 (System 16A)
Symptom: No audio
Replaced audio amp IC and recapped the audio section. Tested.
NOTE: Quartet 2 on the large board has specific wiring that must be done along with a 100 ohm 10w audio pot to keep from damaging the audio output IC. It will sound garbled when connected through a Sega System 16B to JAMMA adapter.
-
Model: Quartet (System 16A)
Symptom: Dead
Board was missing the 68000-10 CPU
Replaced missing CPU. Replaced 2 dead 74LS244 bus buffers and patched a bad trace to restore CPU activity. Board appeared to be dead, but would boot into diagnostics with an error at E8. Replaced a bad 74LS273 in the circuit that combines the layers into one video output to fix the error. Game would still not boot. Found and repaired a broken leg on the security CPU. This fixed the halo colors around IC CHECK, but did not resolve the other issues. Connected a Quartet 2 ROM board and the game would play, but with no background or foreground objects. Replaced a bad 74LS374 in the video combining circuit to restore those. Reinstalled the Quartet ROM board and the game would then play.
NOTE: Quartet on the large board has specific wiring that must be done along with a 100 ohm 10w audio pot to keep from damaging the audio output IC. It will sound garbled when connected through a Sega System 16B to JAMMA adapter. It also has special 4 player wiring and will not map to controls using a JAMMA adapter.
-
Model: Golden Axe
Symptom: Corrupt Graphics
Removed 6 corroded sockets and ROMs. Cleaned PCB area. Replaced the 6 corroded Mask ROMs and sockets. Tested.
-
Model: Shinobi
Symptom: Dead.
Replaced 4 bad sockets and one corroded EPROM. Replaced the suicide sound CPU module with a Z80B and replaced the sound program ROM with one using suicide-free code. Tested.
-
Model: Quartet
Symptom: Dead
Straightened multiple bent pins touching traces on the bottom side of the PCB. Tested.
-
Model: Altered Beast
Symptom: No Audio
Replaced dead custom CPU with a Z80B and replaced the Sound Program ROM with one using suicide-free code. Tested.
-
Model: Shinobi (16A)
Symptom: Dead. Stuck in watchdog
Board had corrosion damage on the top side of the PCB.
Ran 9 trace patches across the bottom side of the PCB and 6 on the top side. Program ROMs were not being read. Pin 22 was stuck high. Replaced bad LS157, LS155, and ALS138 chips with stuck or chattering outputs. Still stuck in watchdog. Replaced stuck ALS04 and a bad 68K CPU. Now had mostly correct signals on the CPU, but it was still stuck in watchdog. /HALT was chattering along with RESET and /AS, /UDS, and /LDS were stuck high while /BGACK was chattering. Pulled pin 12 of the programmable logic chip driving the /BGACK signal out of socket and the board booted and ran. Replaced bad 74LS161 chip with a chattering output to fix the stuck /BGACK signal to the CPU. This stuck signal caused the CPU to not boot as it thought another CPU was accessing a shared bus.
-
Model: Shinobi (16A)
Symptom: Burned edge connector
Repaired edge connector with copper trace tape and tested.