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, 08:26:22 PM
-
Fixed: Suzuka 8 Hours 2
Symptom: Missing background graphics
Fixed bent pins on 2 ROMs and reset the dip switches on the video board. Now the road shows up. The DIP switches on the video board can be turned on and off to activate/deactivate the different video layers - road, background, player, etc, and someone had changed them in their attempt to find the problem.
Can't fully test it as I don't have the wiring harness and controls to test the motorcycle controls.
-
Game: Galaga3 (Gaplus)
Symptom: Dead
The power supply board had 2 problems. First battery on the power supply board had leaked and corroded quite a few components. The second was a blown 3/8 amp slo-blo fuse that someone had replaced with a 7 amp (!!!) fuse that blew as well. Replaced a cracked 10 ohm 5 watt resistor, 1N4001 diode, a shorted 4.7uf tantalum capacitor, and the shorted LM305 voltage regulator. Cleaned the circuit board and replaced the corroded components as well. Set the 5v line to 5.15v and tested the game.
-
Model: Galaga3
Symptom: Garbled title on the screen
Checked the ROMs and PROMs on the board for proper checksums. Programmed 2 new 82S131/63S241 PROMs to replace 2 PROMs that were for the Gaplus game and not the Galaga3. The title was Galaga3 but the colored outlines were for Gaplus.
-
Model: Tekken 2
Symptom: Corrupt foreground and background grapics.
The main graphics generator chip on the top board had 4 bent pins touching on one corner, 2 bent pins touching on another corner, and 2 bent pins touching on the middle of one side of the chip. Carefully straightened the pins and resoldered them. Problem was better but still existed.
Resoldered 4 SMT RAM chips to fix the rest of the graphics corruption.
-
Model: Tekken 2
Symptom: Lines in foreground graphics. Blocky graphics overall.
When the main graphics chip was tapped the game would freak out. Resoldered the IC and the lines in the foreground graphics were fixed. Resoldered 4 surface mount SRAM ICs to fix the blocky graphics problem. One of the lower address lines were not making good connection on the SRAM.
-
Model: Namco Classics Collection Vol. 2
Symptom: Dead. An IC and capacitor was broken off the board.
The IC and capacitor was included in a bag with the board.
The chip was an MB3771 and controlled the reset line. The capacitor was tied to that chip. Only 2 pads (power and ground) remained for the surface mount MB3771 chip. Cleaned the board, ran continuity checks, and referred to the data sheet to determine how the chip was wired into the circuit. Tacked down the IC, soldered it to the pads, and ran 30ga Kynar wires to connect the remaining pins.
Tested the capacitor then resoldered it to the board. Ran the last jumper wire connection to the capacitor and played a few games to test it.
-
Model: Namco Classics Volume 1
Symptom: Streaking video
Video was streaking badly. Solid colors looked striped and smeared down the screen. Replaced leaking surface mount caps C13, C14, and C15. Tested.
-
Model: Namco Classics Volume 1
Symptom: Reboots at random
Board would reboot if jostled or tapped. Reflowed the surface mount IC at 3E and tested.
-
Model: Namco Classics Vol 2
Symptom: Player 2 will not move down or left
Tested the buttons connections at the JAMMA edge connector. They properly were held at +5v and would go to ground when the controls for player one and player two were activated. Tested the Murata EMI filters. Checked the logic levels at the 74HC257 chips as the buttons and sticks were tested and they were all proper. Replaced the surface mount 74HC257 at 10A to fix the game. Tested.
-
Model: Namco Classics, Vol 2
Symptom: Dead. Missing parts.
Board came in a box of misc boards. Installed 3 missing EPROMs and 7 missing capacitors. Patched a bad trace between the CPU and the program ROMs. Tested.
-
Model: System 246 I/O board
Symptom: No sync
Board had severe burn damage and was in a cabinet that had improper wiring/grounding. The filter chokes were good but the trace coming off the filter choke and going to the HD-15 VGA connector was burned through. Jumpered burnt trace.
-
Model: Namco Classics Vol 1
Symptom: Player 2 will not start. Garbled audio
Board will also reboot when test switch input pin on 10A is touched with a logic probe.
Replaced bad IC at 10A and 11A to fix player 2 inputs. Patched a bad plated thru hole to fix test switch issue. Replaced bad audio amp IC (LA4705) to fix audio issue. Tested.
-
Model: Numan Athletics
Symptom: Randomly dies
Removed a short from the daughter board connector. Replaced all surface mount electrolytics as they were leaking and failed ESR tests. Resoldered custom surface mount IC C218 and tested.
-
Model: Namco Classics Vol. 1
Symptom: Streaks in video, missing inputs for player 2
Replaced 6 leaking surface mount electrolytic caps in the video output section. Replaced a bad input filter on the player 2 buttons circuit. Tested.
-
Model: Namco Classics Vol. 1
Symptom: Low output on red signal
Replaced 6 bad capacitors in the video output circuit. Tested.
-
Model: Galaga (newer rev board)
Symptom: Constant reboot
Board would go through the self tests, start the 2nd/3rd CPUs then immediately reset.
Replaced bad 74LS259 and bad ROM 5. The electrolytic caps were leaking and corroded their solder connections on top of the board and 1 nearby trace. Replaced all 7 electrolytic caps and patched the damaged trace. Tested.
-
Model: Galaga (newer rev board)
Symptom: Dead. Missing CPU
Installed missing CPU. The electrolytic caps were leaking and corroded their solder connections on top of the board. Replaced all 7 electrolytic caps and patched the damaged trace. Tested.
-
Model: Galaga
Symptom: Dead. Garbage on screen.
Installed Renew Kit (new sockets & resistor packs), cleaned the custom chip legs, and repaired 2 broken pins on the 54XX chip. Board would boot but all moving characters had incorrect colors and boxes around them. Replaced bad PROM 3 on the video board. Tested.
-
Model: Galaga
Symptom: Dead. Garbage on screen
Replaced all of the old 24/28/40/42 pin sockets and all the old style resistor packs on the CPU and Video board. Cleaned custom chip pins. Replaced bad 74107 and bad cap to fix the reset circuit on the CPU board. Board would randomly attempt to boot but otherwise was dead with a white screen. Replaced bad 74LS32 at 4C to fix the R/W circuit on the CPU board. Board would then boot but had corrupt player graphics. Replaced bad 2147 RAM chip at 6M to finish the repair. Tested.
-
Model: Galaga
Symptom: Dead
Replaced all 24/28/40/42 pin sockets and old style resistor packs. Cleaned the custom chip legs and repaired one leg on the 51xx chip. Recapped the audio section and replaced 1 cap in the reset section. Tested.
-
Model: Soul Calibur II
Symptom: Dead
Reseated video cable between PS2 board and I/O board. Cleaned ROM card. Replaced bad DVD drive and cleaned the DVD. Tested.
-
Model: Soul Calibur II
Symptom: No controls
Replaced ribbon cable between the I/O board and the System 246 unit. Tested.
The ribbon cable is NOT twisted on this unit - Pin 1 must match up with Pin 1. If not, the system will "see" the I/O and boot, but none of the controls will work.
-
Model: Ms Pac Man
Symptom: Dead
Repaired burnt edge connector with copper trace tape. Replaced bad ribbon cable between main board and CPU daughterboard. Tested.
-
Model: Ms. Pac Man
Symptom: Dead
Removed excess solder from the edge connector and cleaned the flux from it. Replaced missing Z80 Sync Buss Controller. Tested.
-
Model: Bosconian
Symptom: Dead. Garbage on screen.
Replaced all the old style resistor packs on both the CPU and Video boards. Replaced all the 24/28/42 pin sockets on the Video board. Discovered corrosion on one of the 6116 SRAMs. Cleaned the pins on the SRAM and cleaned the tarnish from all the silver plated pins on the custom ICs. Reinstalled the ICs and tested.
Replaced all the 24/28/40/42 pin sockets on the CPU board. Cleaned the tarnished silver plated pins on all the custom ICs on the CPU board. Reinstalled the ICs and retested.
-
Model: Bosconian
Symptom: No music or speech.
Replaced all the old style resistor packs on both the CPU and Video boards. Replaced all the 24/28/42 pin sockets on the Video board and CPU board. Cleaned the tarnish from all the silver plated pins on the custom ICs. Fixed a broken pin on the 54xx IC. Reinstalled the ICs and tested. Replaced 1 7489 SRAM on the CPU board to fix the music and 1 transistor on the video board to fix the speech.
-
Model: Bosconian
Symptom: ROM 2 error
Replaced all the old style resistor packs on both the CPU and Video boards. Replaced all the 24/28/42 pin sockets on the Video board and CPU board. Cleaned the tarnish from all the silver plated pins on the custom ICs. Fixed a broken pin on the 50xx and one of the 8xx ICs. Straightened a bent pin on the 3rd EPROM to fix the ROM 2 error. Reinstalled the ICs and tested.
-
Model: Grobda
Symptom: Dead
Replaced CPU and tested
-
Model: Galaga
Symptom: Dead
Board had attempted repair damage on the ROMs on row 3 on the CPU board.
Replaced all the 24, 28, 40, and 42 pin sockets on the board. The sockets had been replaced once before, but with defective single wipe sockets and 8 damaged/patched traces. Several of the old sockets had fractured pins that were making intermittent contact with the board. Re-jumpered 7 damaged traces as two of the existing patches under the ROM sockets were intermittent.
Cleaned the custom chips and repaired a pin on each of the 06xx, 54xx, and the 00xx chips. Tested.
-
Model: Bosconian
Symptom: Unknown. Wanted board rebuilt.
Board powered up an ran, but had no audio. Replaced 2 older style resistor packs, all of the 24/28/40/42 pin sockets in use (one extra, unused socket was not replaced), all of the axial electrolytic caps, and a bad MB3730 audio amp chip. Tested.
-
Model: Gaplus
Symptom: Dead
Cleaned corroded ROM legs, Custom IC 34 had several broken legs. Cleaned the remaining legs, placed it in a machine pin socket, and soldered it to the socket. Replaced the 28 pin socket on the board and reinserted it. Resoldered poor solder joints on the crystal oscillator and tested.
-
Model: Galaga 88
Symptom: Poor colors and no sync.
Cleaned edge connector and tested.
-
Model: Gaplus
Symptom: Missing chips. Dead.
Replaced 3 missing CPUs and 1 corroded 64 pin socket. Cleaned the pins on the 64 custom and tested. Game would try to boot. Tested and replaced 4 bad EPROMs. Tested Game.
-
Model: Assault
Symptom: Missing every other vertical line in player graphics
Replaced bad 2018 SRAM chip at 7J on the bottom board. Tested.
-
Model: Point Blank 2
Symptom: Random crashes and garbage on screen
Cleaned top board. Reflowed the Flash ROM, ROMs on the daughterboard, and reseated the KEYCUS chip. Tested.
-
Model: JVS to JAMMA adapter
Symptom: No video
Replaced physically broken surface mount RC filter.
-
Model: Mappy
Symptom: Dead.
Replaced missing crystal on the CPU board. Board came up but had incorrect colors and corrupt graphics. Replaced bad 2148 RAM at locations 3E and 4E on the video board. Board looked much better but had incorrect colors. Replaced bad PROM at location 5K on the video board, replaced missing hardware holding the boards together, and tested.
-
Model: Gaplus
Symptom: Rebuild parts board
Board was missing many components.
Replaced missing 68A09E CPUs at 3A, 8A, and 10A. Replaced missing ROMs at 4B, 8B, 8C, 8D, 8S, 11B, 11C, 11D, 11M, 11N, 11P, and 11R. Board was stuck in watchdog. Inspected bottom of board and repaired a trace to the graphics ROMs on row 11. Checked the shared RAM and found address line A7 was dead. Traced it back to a bad 64 pin socket on the 20xx custom at 8J that had 3 mangled contacts on it. Replaced the socket and tested. The board would not coin up. Swapped the locations of the 56xx and 58xx customs to restore inputs. Replaced one corroded cap in the audio circuit and tested.
Not sure why someone would swap those 2 customs, but it won't do any damage to them if they are swapped.
-
Model: Galaga
Symtpom: Dead
Board had attempted repairs done.
Replaced 4 resistor packs on the video board, replaced all of the original 24/28/40/42 pin sockets on the boardset. Cleaned multiple corroded legs on EPROM chips, cleaned the custom ICs, and tested. Board would partially boot but had the number 3 across the entire screen and would not boot past self tests. Replaced bad Z80 CPU and bad 54xx chip on the CPU board to fix boot issues and a bad 00xx chip on the video board to fix the number issue.
-
Model: Pac-Land
Symptom: Stuck at power-on diagnostics
Board would power up and show a ghost and 3 zeros on the screen. Three zeros = "all good"
Replaced corroded sockets and cleaned chip legs at 1R, 1T, 2R, 3E, 3F, 4N 5R, 5T, 6D, 6E, 6F, 6H, 6L, 6N, 6T, 7E, and 8ED. Replaced bad 74LS257 at 2L and tested. The LS257 was not reading DIPs properly and keeping the system stuck at "all good"
-
Tip: Pac-Land Error Codes and boot issues
Courtesy of cmonkey from the KLOV forums
Pac-Land boots with the screen flipped upside down and displays a ghost and numbers on the screen during self test. A successful self test screen shows a ghost and 0 0 0 before it flips the screen and displays the title screen after this boot process has finished.
If stuck at the upside down 000 self test screen, double check dipswitch B switch 7. That's the FREEZE switch and if it's on when the game boots it'll hang with the boot error codes on screen and go no further until you turn it off.
The upside down error codes are as follows :-
leftmost digit = MCU (sub-cpu) error code (The number furthest away from the ghost)
0 = sub-cpu woke up OK
1 = sub-cpu internal ROM failure or sub-cpu failed to wake up
middle digit = eprom error (only positions 8B, 8D (main cpu) and 3E (sub-cpu) are checked)
0 = all 3 code eproms good
1 = eprom @ 8B failed checksum
2 = eprom @ 8D failed checksum
7 = eprom @ 3E (sub-cpu) failed checksum
rightmost digit = ram error (The number next to the ghost)
0 = all rams good
1 = work ram @ 9M bad (addresses $3000-$37ff)
2 = work ram @ 9N bad (addresses $2000-$27ff)
3 = work ram @ 9P bad (addresses $2800-$2fff)
4 = tile ram @ 9R bad (odd bytes - addresses $0000-$0fff)
5 = tile ram @ 9S bad (even bytes - addresses $0000-$0fff)
6 = tile ram @ 10R bad (odd bytes - addresses $1000-$1fff)
7 = tile ram @ 10S bad (even bytes - addresses $1000-$1fff)
9 = shared ram @ 3J/3K bad (one or both are bad)
The ghost character has no significance, it's merely there to look pretty.
-
Model: Namco Classic Collection Vol. 2
Symptom: Plays blind
Board had burned traces in the video section from being plugged into a cabinet with a miswired monitor. (Monitor should've had an isolation transformer and didn't.)
Replaced bad LM1203 IC and 9 surface mount resistors in the video output section. Replaced 1 surface mount resistor and a 74F04 in the sync output circuit. Patched 2 burned sections of the video ground trace. Tested.
-
Model: Galaga
Symptom: Dead
Replaced all the old style resistor packs and single wipe 24/28/40/42 pin sockets. Cleaned the customs and replaced a bad 07xx on the CPU board. Tested. No sound or controls. Cleaned the edge connector with a fiberglass pencil and retested.
-
Model: Soul Calibur 2
Symptom: No video/audio
Cleaned foreign substance off of the Altera chip on the I/O bard and tested.
-
Model: Galaga
Symptom: Dead
Board had attempted repair damage. Replaced all the old style resistor packs and single wipe 24/28/40/42 pin sockets. Cleaned the customs. Socketed and cleaned up the damage around the 74LS368 at 3N. Removed a solder short from the reset line where an audio cap was improperly soldered in.
Board would now boot to RAM errors. Replaced 2 2114 RAMs and board would boot but had incorrect colors on motion sprites. Replaced bad 2147 at 6K to fix the color issue. Tested.
-
Model: Rally-X
Symptom: Dead. Garbage on screen.
Resoldered popped leg on the the 220uf capacitor. Cleaned legs on the program ROMs and Z80 Sync Buss Controller IC. Replaced 3 bad mask program ROMs with failed checksums. Tested.
-
Model: Galaga
Symptom: Display split in 2 and the number 3 filling 1/2 the screen.
Replaced all old style resistor packs and old sockets. Cleaned the custom IC and tested the board. Board would boot, give the explosion sound, and reboot again before working. Replaced bad 06XX custom and retested.
-
Model: Galaga
Symptom: Dead. Garbage on screen.
Replaced bad Z80A CPU and tested.
-
Model: Galaga
Symptom: Dead, incorrect colors on screen.
Installed all new 24, 28, 40, and 42 pin double wipe sockets and cleaned the legs on the custom ICs before reinstalling. Cleaned the pins on the 2k x 8 SRAM at 1K on the video and the board booted and played, but with a yellow tint to everything on the screen. Cleaned the legs on the PROM at 5N on the video board to fix the color issue and retested.
-
Model: Rally-X
Symptom: Damaged edge connector
Replaced a staple (?!?!?!?!) being used as an edge contact with copper trace tape and tested board.
Used this board repair to make a video for our YouTube channel: https://www.youtube.com/watch?v=RdLDlAl2iWo (https://www.youtube.com/watch?v=RdLDlAl2iWo)
-
Model: Galaga
Symptom: Dead. Attempted repairs had been done.
Removed all the 24/28/40/42 pin sockets to install new ones and found one pin on the socket at 1H on the video board that was broken at the socket body. Fixed two shorted solder pads to an adjacent trace on the 74LS259 at 3C on the CPU board. Fixed two pins that were bent under the chip on a 08xx and the 51xx custom ICs. The broken socket would've made the board intermittent and the two shorted solder pads rendered it non-working. The bent under pins on the 08xx would've rendered the board dead and on the 51xx would've affected one of the inputs from the controls.
Installed new 24/28/40/42 pin sockets. Replaced bad RAM at 5E to fix a "RAM 2L" error. Tested. Cleaned the pins on the PROM at 5E to fix a flickering brightness issue and retested.
-
Model: Galaga
Symptom: Random crashes/resets
CPU board had been repaired in the past by Eldorado Games and had machine pin sockets installed.
Replaced the single wipe 24/28 pin sockets on the video board and cleaned the custom IC legs. Tested.
-
Model: Galaga
Symptom: Dead
Board had attempted repairs done to it. The 2147 RAMs were removed and replaced with 2 2148 RAMs by another person.
Removed a solder short between pin 14 of IC2L that was shorting the data bus and returned the board to life. The game ran but had missing lines in the sprites and corruption in the crosshatch screen. Replaced a broken unencapsulated resistor pack to fix the crosshatch and removed a solder short between pins 2 and 16 of the removed 2147 at 6M to fix the sprite issues.
Replaced the remaining unencapsulated resistor packs and all of the 24, 28, 40, and 42 pin sockets. Tested.
-
Model: Galaxian
Symptom: Dead. Missing parts.
This is the early Namco ROM version board with the harder ROMs.
Installed a missing ROM board and ROMs at 1H and 1K. Installed missing RAM at 1N, 1P, 1R, 1S, and 1T and a missing 74LS245 at 5J.
Replaced the 2114 RAMs at 3F/3H and popped a diagnostic ROM on the board to test the rest of the RAM. Replaced bad CPU RAM at 7N and 7P. Retested and replaced a bad RAM at 4F. Since the other RAMs were also bad I replaced the RAM at 5F for good measure. Retested and board had graphic corruption and would randomly lock up and reboot.
Replaced 74LS161 at 3A to fix the lockup. The corruption was interesting - when you shot an alien the whole row would turn the color of the explosion and when aliens from the upper rows dove down the rows they went over would change colors. The text showing alien scores in attract mode was the wrong color. Replaced ICs at 5C, 4D, 2M, and 2N since they had corrosion on the pins and cleaned/tested the traces under them. Broke out the logic comparator and found pin 3 on the 74LS32 at 3S had an incorrect output. Replaced the IC and tested the game successfully.
-
Model: Suzuka 8 Hours 2
Symptom: Dead. No sync.
Board had attempted repairs - a resistor in the sync section was replaced and a jumper wire installed around a burned trace.
Replaced a bad 74AC240 at A2 to restore sync. It had sync signal the gate input but the output was stuck high. Board would boot but had a Sub CPU error. Replaced missing Sub CPU ROM at 13K and tested.
-
Model: Namco Classics Volume 1
Symptom: Streaking graphics
Replaced 1 47uf, 1 100uf, 1 10uf, and 3 4.7uf surface mount caps in the video amp section. Tested.
-
Model: Galaga
Symptom: Dead. Had attempted repair damage.
Board had been worked on by another tech and all of the 24/28/40/42 pin sockets on the CPU board had already been replaced.
Fixed 3 solder shorts, resoldered a pin on a 74LS367 that was desoldered (?!), replaced 3 08xx and 1 07xx ICs that had multiple missing pins, and replaced all of the old style resistor packs on the CPU board. Tested and found a dead Z80A on the CPU board then retested successfully with a good video board.
Replaced all of the 24 and 28 pin sockets on the video board, repaired a broken leg on the 00xx IC, and replaced a missing board standoff. Game would boot to a 2L error. Replaced bad 2114 RAM at location 3E and retested successfully.
-
Model: Galaga (from hell)
Symptom: Dead with a sticker that said "frozen." Attempted repairs were done to the video board
Replaced the resistor packs on the video board. Replaced 2 bad 2114 RAMs and the 2K SRAM IC and tested with a known good CPU board. The game would run through self tests for about 4 seconds then freeze. Removed solder short from 2 pins on the 50 pin board interconnect and retested the video board successfully.
Replaced the 24/28/40/42 pin sockets and resistor packs on the CPU board. Replaced the 06xx, 3 x 08xx, the 07xx customs, and ROMs at 3K, 3L, 3M, and 3N because of multiple leg failures. Installed a missing 54xx custom and tested. Board would not boot. Replaced bad 74LS139 at 4P and board was then stuck in watchdog. Replaced all 3 bad Z80 CPUs and tested. Board would try to boot but fail with random errors and the address lines were garbled on the far side of the 74LS367 address bus buffers. Replaced all the 74LS367 and the board would boot further but still had no digital sound effect/music, locking up randomly, and garbled static out of the speakers. Replaced bad 74LS138 chips at 1P and 2P to get rid of the garbled static. Replaced the 74LS32 ICs at 3P and 4C and the 74LS259 with rotted legs at 3C to fix the lockups. Replaced 2 bad 7489 RAMs and a 74LS283 in the sound section to restore the music and digital sounds.
Connected the 2 boards together and tested for an extended burn-in.
Every chip on the CPU board that touched the address buffers on the far side away from the CPU had some kind of damage.
-
Model: Galaga
Symptom: Dead
Replaced all the 24/28/40/42 pin sockets on the CPU board and tested with a known good video board. Board would lock up at the OK screen. Replaced bad Z80A CPU and retested. Board would boot and play but would display "READY" on the screen when the aliens try to steal your ship. Board would then randomly freeze the player ship in place and letting shots pass through it before displaying "GAME OVER" on the screen and ending the game mid-play. Replaced bad 08XX chip at 2J and restested successfully.
Replaced all the 24/28/40/42 pin sockets on the video board. Repaired a broken pin on the 00XX custom IC then tested. Replaced bad 2114 RAM and retested successfully.
-
Model: Galaga
Symptom: Dead. Nothing on screen.
Board had a rebuild kit installed and had damage done by another tech during the install.
Video board was only at 3.6v DC and would not go above that. Inspected the board and found the 02xx IC in backwards and the 05xx in the wrong socket. Replaced the 02xx chip and put the 05xx back in the proper socket. Replaced the filter capacitor and cleaned leaking electrolyte off the board. Replaced corroded board interconnect. IDed the character ROMs and put them back in their proper sockets. Board would not boot. Removed multiple solder shorts, replaced bad 2k SRAM IC, and replaced a bad 74LS245 at 2H. Board would boot with a known good CPU board but had graphic corruption. Repaired 3 broken traces to fix characters and 1 broken trace to the color PROM at 1C to fix color boxes around characters. Tested with a known good CPU board.
CPU board was dead. Repaired multiple shorted traces, replaced corroded CPU sockets at 4J and 4M, and repaired a broken trace on the CPU at 4J. Replaced damaged EPROM socket at 3L and corroded sockets at 3M and 3N. Replaced dead program ROM at 3N. Replaced physically damaged socket on the 06xx IC and repaired 4 traces between it and the 08xx custom next to it. Repaired a burned trace on resistor pack RM22 next to DIP switch 6K. Board would not boot and would constantly crash/reboot or stop at RAM 0L errors. Replaced a bad 74107 at 5B and board would boot but stick on RAM OK. The CPU at 4E would not start. The Fluke 9000A pod errored out with a CTL ERROR message and pin 20 would never go low to allow for a read of the EPROM at 3E. Replaced a bad 74LS139 at 4B and removed a solder short between pin 24 of the CPU at 4E and the ground pin under the socket of the 07xx IC at 4D. Tested. Board would boot but had no explosion sounds. Replaced 4 broken mylar capacitors and cleaned the pins on the 54xx custom. Tested.
-
Model: Galaga
Symptom: Graphic corruption after a couple of minutes
Replaced all the 24/28/40/42 pin sockets, 50 pin ribbon cable, and checked the newer style resistor packs. Replaced 6 2114-4 RAMs with 2114-2 to fix random lockups. Replaced bad 06xx custom that caused the board to go into a boot loop when the game was rebooted while warm. Tested.
-
Model: Galaga
Symptom: Reboots
Replaced all 24/28/40 pin sockets and inspected the customs that were soldered directly to the board. Fixed a solder short on the 51xx custom IC. Recapped the boardset, reset the DIP switches, and tested.
-
Model: Galaga
Symptom: Dead. Repeating thump coming from speakers.
Board had attempted repair damage in audio section. Pads and traces were burnt and gone to the audio amp chip.
Recapped the audio section, replaced the wire hacks, and patched missing ground trace to fix audio thump issue. Installed renew kit with new sockets and resistor packs. Tested.
-
Model: Galaga
Symptom: Dead
Sender had attempted to install a rebuild kit and had installed sockets and resistor packs on the CPU board and resistor packs on the video board.
CPU Board: Removed solder short under the CPU socket. Removed solder short under the 06xx socket. Patched pulled trace on pin 1 of the program ROMs for CPU 1. Board booted with a known good video board but had no attract mode sound. Patched a damaged trace on one of the 4.7k resistor packs next to the DIP switches and tested with a known good video board.
Video board: Installed the 24/28 pin sockets. Resoldered a couple of the resistor packs. Reinstalled RM4 the correct way and tested. Stuck on white screen. Replaced all the 2114 RAM as 5 of 6 were bad. Still stuck but if you press reset on the CPU board you get a 0L or 0H RAM error. The /OE and /CE lines were stuck low on the 16K SRAM. Replaced bad 74LS08 at 1D and tested the game.
-
Model: Galaga
Symtpom: Reboots
Installed renew kit, reset DIPs and tested. Player and red enemies were striped yellow. Replaced bad RAM at 6K and retested.
-
Model: Galaga
Symtpom: Plays blind with only starfield on screen. Hot glue everywhere and all the customs on the video board were soldered directly to the board. :(
Replaced several incorrect resistor packs, 2 resistor packs that were simply discreet resistors soldered to the board, and all of the unencapsulated resistor packs. Replaced all the single wipe 24/28/40/42 pin sockets that hadn't already been replaced. Desoldered the 02xx IC, cleaned the board, installed a double wipe socket, and inserted a replacement IC to fix the video issue. Tested.
-
Model: Namco Classics Vol 1
Symptom: Dead
Replaced corroded socket for NC1 MAIN0 ROM and repaired a bad leg on the ROM. Reflowed the C416 custom IC and the 2 ROMs at 1E and 2E. Cleaned dirty legs on the SUB ROM NC1 and replaced the bad cap at C55. Tested.
-
Model: Tekken 2 Ver. B
Symptom: Garbage on screen, stuck on boot loop
Found a spill damaged trace. Cleaned and then patched it with 30ga Kynar wire and tested. Replaced a broken off 100uf @ 6v SMT cap on the 3.3v power line on the video board and retested.
-
Model: Ms. Pac / Galaga Reunion
Symptom: Terrible audio and burned edge connector
Patched the burned video ground trace, replaced a bad/dirty volume pot, and tested. The video would come and go. Reflowed a corner of a custom surface mount chip and retested.
-
Model: Galaga
Symptom: Terrible buzzing sound in audio. Overpowers all sounds.
Isolated the noise to between R19 on one side of the board and the output resistors on the 4066 chip on the other side of the board. Followed the traces and found a solder short between that trace and one of the traces go the 51XX I/O chip. Removed the solder short and successfully tested the board.
-
Model: Galaga
Symptom: Random errors, screen unstable
Installed rebuild kit and tested. Board had no sound and picture was unstable. Replaced a bad 74LS368 in the clock circuit to fix the screen and random error issue. Replaced the sound caps and a bad MB3730 audio amplifier IC. Tested.
-
Model: Galaga
Symptom: Crashes
Rebuilt boardset with new resistor packs and sockets. Replaced 2 broken standoffs. Replaced radial caps on the board with proper axial capacitors. Tested.
-
Model: Galaga
Symptom: No text on screen. Crashes.
Replaced all the 24, 28, 40, and 42 pin sockets and all of the old style resistor packs. Reattached ribbon cable connector cover and installed 4 missing standoffs. Game would boot without crashing but had no text on the screen. Replaced a bipolar PROM that was plugged in backwards and retested successfully.
-
Model: Galaga
Symtpom: Missing ROM @ 3J and custom @ 2E on CPU. Video has 1 up and score on left side of screen as well as top of screen. Video has Free Play on right of screen as well as bottom of screen.
Replaced all the 24, 28, 40, and 42 pin sockets. Replaced 4 broken PCB standoffs. Replaced missing ROM and custom IC and tested.
-
Model: Galaga
Symptom: Will not always boot
Replaced all the 24, 28, 40, and 42 pin sockets. Repaired broken pin and 1 bent pin (that was out of the socket) on the 05xx starfield generator. Replaced 3 1K 5pin resistor packs and a broken capacitor at C4 on the video board. Tested.
-
Model: Galaga
Symptom: Bad 2147 RAM. Wants board rebuilt.
Replaced the 24, 28, 40, and 42 pin sockets. Replaced 1 bad and 1 incorrect cap on the output of the audio amp IC. Replaced 2 radial caps with the correct axial caps in the audio amp section. Replaced short board standoffs with the correct type. Replaced 1 bad 2147 RAM and tested.
-
Model: Galaga
Symptom: Rustling noise in audio. Amplifier gets very hot.
This one was an odd one! Isolated the 4066 IC and the LM324 from the audio output circuit. No change. Removed the volume pot and the noise went away. Replaced the pot and the noise returned. Replaced C18, a .1uf monolithic capacitor between the volume pot and the audio amplifier IC to fix the issues.
-
Model: Galaga
Symptom: Dead
Replaced all the 24, 28, 40, and 42 pin sockets. Replaced the old style resistor packs and repaired broken legs on the 05xx, 07xx, 06xx, and 54xx customs. Replaced the 470uf 5v filter caps and tested. Game would boot and play but had noise in the audio output and the amp would go into oscillation and draw excessive current. Replaced the 3 electrolytics in the audio section and retested successfully.
-
Model: Galaga
Symptom: No sprites and bad music
Board had previous work done to it.
Replaced all the 24 pin sockets. Replaced 4 incorrect resistor packs and 4 discreet resistors with the proper resistor packs. Recapped the audio section and replaced the 2 470uf filter caps. Tested.
-
Model: Galaga
Symptom: Dead
Board had the Galaga Enhancement pack installed.
Replaced all the 24/28/40/42 pin sockets then replaced all the old style resistor packs on the video board. Tested. Board would boot but not recognize any inputs. Reset the DIP switches to factory standards and tested. Set DIPs to free play and retested.
DIP 5 on the 2nd DIP switch bank causes reboot loops on some ROM revisions. On this one with the enhancement pack it caused inputs to be ignored. Odd.
-
Model: Galaga
Symptom: Dead
Replaced all single wipe 24, 28, 40, and 42 pin sockets. Replaced all the unencapsulated resistor packs. Cleaned corroded pins on CPU 2. Replaced the 02XX chip and 05XX chip due to bad leg rot. Tested.
-
Model: Galaga
Symptom: Dead
Board had previous repairs done to it.
Replaced all single wipe 24, 28, 40, and 42 pin sockets. Fixed 2 bad solder joints on the program ROMs for CPU 1 and removed a solder short on the program ROMs for CPU 1. Repaired a broken pin on the 08XX chip for CPU 1. Tested. Replaced the broken plastic standoffs and retested.
-
Model: Galaga
Symptom: Dead
Board had previous repairs done to it.
Replaced all single wipe 24, 28, 40, and 42 pin sockets. Replaced 3 radial caps in the sound section and 1 radial cap in the reset circuit with proper axial caps. Tested. Board ran fine but had garbled sound. Replaced bad 7489 bipolar RAM at 2B and tested. Replaced the broken plastic standoffs and retested.
-
Model: Galaga
Symptom: white screen. Will not boot.
Replaced the 24, 28, 40, and 42 pin sockets. Replaced the old style resistor packs. Tested. Replaced the 6116 SRAM and tested successfully.
-
Model: Galaga
Symptom: RAM Error 2L, random vertical lines around screen
Replaced the 24, 28, 40, and 42 pin single wipe sockets with dual wipe. Replaced 470uf cap on the video board. Replaced all the unencapsulated resistor packs on the video board. Board booted to RAM Error 2L. Replaced the RAM at 3E and tested successfully.
-
Model: Galaga
Symptom: Dead. White Screen
When the board was received it had nothing on the screen. Looking at the video board, the 07xx was found to have a broken pin 28 (Vcc, a.k.a. power) which rendered it dead. It's the clock divider IC. Fixed the pin and the board was stuck on the white screen. Tested the 2k x 8 SRAM IC from the video board and it was good.
Installed new 24, 28, 40, and 42 pin sockets and replaced all the old style resistor packs. The CPU board appeared to have water damage and was speckled in appearance with corrosion under the plastic sleeves of the electrolytic caps. When the customs were removed from their sockets they lost multiple legs. Replaced all 6 customs on the CPU board. Cleaned corroded legs on the CPUs and all ROMs. Replaced the power filter and audio caps then reassembled and tested. The board booted to RAM 2L. Replaced a bad RAM chip then the board booted to RAM 3H. Replaced another bad RAM chip and the board booted and played. Burned the board in.
-
Model: Galaga
Symptom: Dead. Garbage on screen
Resocketed the CPU and video boards. Unit already had the newer style resistor packs. Replaced bad 08xx with multiple broken legs. Replaced bad 6116 RAM. Replaced a bad 74LS32 at P3 that had a short between pin 1 to +5v of 150 ohms. Board would boot but reboot when starting CPUs 2 and 3. Swapped the E and G ROMs and retested successfully.
-
Model: Galaga
Symptom: Dead. Audio IC was already desoldered and missing pins.
Replaced all the 24, 28, 40, and 42 pin sockets and all the resistor packs as they were all unencapsulated. Replaced the 4 board standoffs with the proper ones as they were too short. Replaced audio IC and one 08xx IC then powered it up to a RAM error and thumping audio. Recapped the audio section and replaced the 2 470uf axial power filter caps to fix the audio issue. Replaced a bad 2114 RAM at 3L to finish the repair.
When the power filter caps on the +12v line fail, the audio amp goes into oscillation making a thump thump thump sound and getting very hot. If the volume is up very high you may notice such a huge current draw that it causes the +5v line on the power supply to dip. Replacing the electrolytic capacitors in the audio section is the usual cure for this.
-
Model: Galaga
Symptom: Dead
Board had an attempted repair as the 07xx chip was soldered to the board, and was missing multiple legs. (Why solder it in with missing legs???)
Board had the encapsulated resistor packs from the factory. Replaced the 24, 28, 40, and 42 pin sockets. Repaired one broken leg on the 02xx chip with a donor chip leg. The 07xx, 04xx, and 05xx chips had multiple legs fall off so they were inserted into machine pin sockets and soldered to the sockets to repair them. Reinstalled the repaired customs and successfully tested the board.
-
Model: Galaga
Symptom: Dead
Replaced all the old TI dual-wipe sockets that make contact on the skinny side of the chip pin instead the wider part. The resistor packs were encapsulated and OK. Replaced one bad 08xx with terrible leg rot. Tested.
-
Model: Galaga
Symptom: Dead. Parts board.
Board was missing the 06xx, 07xx, one 08xx, and the 54xx customs. it was also missing 3 of the 1K 5pin bussed encapsulated resistor packs from the CPU board and one of the 2114 RAMs on the video board.
Replaced all the 24, 28, 40, and 42 pin sockets on the CPU board. Fixed 2 broken legs on one 08xx chip and 1 on the other 08xx that were there. Installed the missing resistor packs. Replaced all of the 24 and 28 pin sockets and unencapsulated resistor packs on the video board. Replaced a missing 2114 RAM. Repaired 2 broken legs on the 04xx custom. Powered up the board and had static in the sound. Recapped the audio section and replaced the 2 5v filter caps. Static was still there. Replaced a faulty volume pot and retested game.
-
Model: Mappy
Symptom: Dead
Board was physically damaged
Replaced 6 2200 ohm 9-pin resistor packs, 1 smashed EPROM, and 1 split in 2 74LS00 IC. Replaced a broken axial filter cap, a broken .1uf bypass cap, and patched a gouged trace. Powered up board to be greeted by a RAM 7 error. Replaced a bad 2114 RAM on the CPU board and retested successfully.
-
Model: Galaga
Symptom: All 'A' or 'O' on the screen. Won't boot
Replaced all the 24/28/40/42 pin sockets and all the old unencapsulated resistor packs. Tested.
-
Model: Galaga
Symptom: Dead. Garbage on screen
Replaced all the 24, 28, 40, and 42 pin sockets. Resistor packs were of the OK type. Board booted up to horizontal lines on the screen, an R for RAM Error, but garbage on the rest of the screen, obscuring the message. Replaced bad 74LS273 at 2C that was dragging down Data Bus C. Board would then boot, but sometimes not boot. Replaced bad 06xx and bad Z80 CPU at location 4E. Tested and burned in board.
-
Model: Galaga
Symptom: Dead
Replaced 24, 28, 40, and 42 pin sockets. Fixed bad pins on 2 customs and replaced 2 incorrect filter caps. Tested.
-
Model: Galaga
Symptom: Dead
Replaced all the 24/28/40/42 pin sockets and all the old style resistor packs. Tested. Character would not move to the left. Fixed a solder bridge under a resistor pack and retested.
-
Model: Gaplus
Symptom Won't boot
Missing audio amplifier IC, heatsink, and hardware
Game would boot then lock up. Replaced bad 68A09 CPU and fixed a bad pin on custom 34. Tested, no sprites. Replaced bad custom 20xx IC to fix the sprites. Fabricated a replacement heatsink and replaced the missing LA4460 audio amplifier IC. Tested.
-
Model: Galaga
Symptom: Reboots. Screen flips
Replaced all the 24/28/40/42 pin sockets and tested. Replaced bad ribbon cable and retested.
-
Model: Super Pac Man
Symptom: Double credits
Board was ignoring DIP SW 3 settings. Tested customs by substitution to no effect. Replaced cracked resistor pack RM16 and tested.
-
Model: Pac Land
Symptom: Garbage on screen
Repaired multiple broken legs on Custom 34. Replaced bad socket. Replaced missing Custom 98. Replaced bad 2k x 8 SRAM IC. Tested.
-
Model: Tekken 2 ver B
Symptom: Graphics corruption
Problem followed the motherboard.
Reflowed the 195 custom and reset the EEPROM. Tested.
-
Model: Tekken 2 ver B
Symptom: Missing color
Replaced damaged 10uf SMT capacitor and tested.
-
Model: Galaga
Symptom: Won't boot
Board had attempted repairs on the CPU board.
Removed all the individual resistors and the 10 pin resistor packs and installed proper resistor packs. Removed radial caps from the sound and reset circuit and installed proper axial caps. Rebuilt the video PCB with new sockets and resistor packs. Tested. Board would reset once during the boot up process. Replaced the 06xx chip and retested.
-
Model: Galaga
Symptom: Will not boot.
Rebuilt a replacement CPU board for the boardset. Rebuilt the video PCB and replaced a dead PROM chip that was plugged in backwards. Replaced the Graphics ROM at 4D which had the "terror" mod code on it with a regular Galaga ROM. Tested.
-
Model: Galaga
Symptom: Dead. Stripped parts boards + extra video board.
Replaced all the 24/28/40/42 pin sockets and unencapsulated resistor packs on CPU and extra video board. Installed missing chips on the CPU board, fixed multiple broken pins on the 05xx custom, and tested to find graphic corruption when the board heats up. Replaced bad video RAM and retested.
-
Model: Galaga
Symptom: RAM error
This one was being rebuilt as a premium build for sale.
Replaced all the 24/28/40/42 pin sockets and unencapsulated resistor packs. Replaced the 8 2147 RAMs with 2 2148 RAMs to run cooler. Replaced all the 14, 16, 18, and 20 pin sockets. Hand picked replacement custom ICs from stock to not have silver plated steel legs. Replaced all the electrolytic capacitors. Tested.
-
Model: Mappy
Symptom: Garbage on screen
Cleaned legs on the CPUs and on the main PAL chip. Replaced a bad socket on the main CPU. Replaced bad socket on the PAL connected to the main CPU. Replaced dead RAM on CPU board. Booted to RAM error. Replaced the other RAM on the CPU board. Rebooted to find stripes in sprites and the game locking up when warm. Replaced bad main CPU and one bad video RAM and retested. Still had sprite failures when warming up. Replaced the other video RAM. Board booted but then had random sprite glitches. Cleaned corroded pin on a ROM on the video board and tested. Board played but had very low audio. Replaced 2 electrolytic caps in the audio section and tested.
-
Model: Mappy
Symptom: Locks up
Board did not boot. Replaced ribbon cable and tested. Board locked up with sound glitching. Replaced sound CPU and retested.
-
Model: Galaga
Symptom: Crashes/Reboots
Replaced all the single wipe 20/24/40/42 pin sockets and replaced all the unencapsulated resistor packs. Repaired a leg on the 00xx custom. Soldered the 05xx starfield generator onto a 24 pin machine pin socket and patched 4 broken legs on it. Tested.
-
Model: Galaga
Symptom: Crashes/Reboots
Replaced all the single wipe 20/24/40/42 pin sockets and replaced all the unencapsulated resistor packs. Tested.
-
Model: Galaga CPU board
Symptom: None: Rebuild
Replaced all the single wipe 20/24/40/42 pin sockets and replaced all the unencapsulated resistor packs. Patched two broken legs on the 08xx custom on the Main CPU section. Tested with the shop bench set of Galaga boards.
-
Model: Galaga
Symptom: Crashes. Sparkles on screen.
Replaced all the single wipe 20/24/40/42 pin sockets and replaced all the unencapsulated resistor packs. Removed a solder short from the video PCB. Replaced the severely damaged ribbon cable that was making contact with the PCB component legs. The CPU board would reboot if tapped with a finger. Replaced 4 16-pin sockets and 1 14-pin socket that only made contact on the skinny side of the chip legs. Now the board can be jostled on the bench and rapped with a screwdriver handle with zero reboots. Burned in PCB for 5 hours.
-
Model: Ms Pac Man
Symptom: Loses sound
Note: A chip had previously been replaced (poorly) on the Sync Bus controller.
Replaced bad socket at 8A. Replaced a 74LS74, socketed it, and patched the ham fisted damaged trace on the sync bus controller. Fixed damaged edge connector and burned it in for several hours without issue.
-
Model: Ms Pac Man
Symptom: No ghosts or Ms Pac. Text missing on intro.
Replaced a bad 74LS158 at 3A. Pins 4 (1Y) and 5 (2A) were shorted together with a reading of 20 ohms.
-
Model: Ms Pac Man (Single ROM hack)
Symptom: Barn find. Test and repair if necessary.
Cleaned and repaired the burnt edge connector. Cleaned the Character ROM legs at 5E/5F to fix lines on the screen issues. Cleaned the pins on the daughterboards and replaced both the sacrificial socket and the socket on the board for the VRAM addresser. Tested.
-
Model: Galaga
Symptom: Dead. Locked up.
Board had previous repairs, damaged from those done to it, and an oil residue sprayed on the board and in sockets.
Cleaned both PCBs and the custom chips to remove an oily residue. Replaced all the non-machine pin 24, 28, and 40 pin sockets. Patched a lifted trace on the CPU board and the boardset booted, but was frozen. Removed a solder short on one of the Program ROMs and tested. Screen colors were off - blue was missing. Patched an open trace on the blue video output and tested. Replaced the broken board standoffs and tested again.
-
Model: Super Pac Man
Symptom: Randomly goes crazy
This one took a while to find. Game would count 2 credits when coined up once. Reset DIP 5 on the 2nd switch bank - it has no function according to the manual, but on counts pulses twice. Checked inputs to the 56xx custom and the 74LS157 for correct DIP switch settings. Found the resistor pack on the switch at 5E was bad, the pin for +5v separated from the body of the resistor pack. Replaced it and tested.
-
Model: Galaga
Symptom: Dead, garbage on screen
Replaced all 24/28/40/42 pin sockets and unencapsulated resistor packs. Replaced bad ribbon cable causing intermittent reboots and crashes. Recapped audio to fix loud static on power up. Patched dead trace between pin 13 and 14 on the 02xx chip to fix color issues on sprites moving upward. Tested.
-
Model: Ms Pac Man
Symptom: Dead. Garbage on screen.
Board had ham fisted attempts at repairs done.
Replaced hacked in CPU socket and patched 2 screwdriver damaged traces under the socket. Replaced bad sockets for the Sync Bus Controller and VRAM Addresser module. Desoldered hacked sacrificial socket from the Sync Bus Controller module and replaced it. Replaced a repair-attempt damaged VRAM addresser module. Replaced damaged sockets at 6E and 6F. Installed replacement ROMs at 6E, 6F, and 5F. Installed missing CPU and tested. Game ran as Pac Man, but not as Ms Pac Man. Replaced bad ribbon cable and tested. Repaired burned edge connector and tested.
-
Model: Pac Man
Symptom: Dead. Nothing on screen
Replaced bad 74LS368 and socket and missing output PROM at 7F. Replaced bad sockets on the Sync Bus Controller and VRAM Addresser. Replaced sacrificial socket on the Sync Bus Controller. Board booted to orange screen. Replaced bad PROM at 4A. Board had mismatched ROMs. Pulled extra ROM and replaced missing ROM at 6F. Board was stuck in a boot loop. Replaced bad ROM at 6H. Cleaned CPU legs and tested.
-
Model: Galaga
Symptom: Missing lines in sprites
Rebuilt the PCB - Replaced all 24/28/40/42 pin sockets and the unencapsulated resistor packs. Replaced bad 74LS157 at 4A. Tested.
-
Model: Tekken
Symptom: Dead. Color bars on screen.
Replaced missing YCUS IC. Board then went through random resets, sometimes won't boot, and had static for sound. Reflowed the 2 SOJ SRAMs, the 74F04, and the 74AC74 down in the corner of the lower PCB. Tested.
-
Model: Super Pac Man
Symptom: Dead
Boardset had corrosion issues.
Removed 2 jumpers and reinstalled 2 missing 100 ohm resistors on the CPU board. Replaced a bad 74LS74 at 2A to restore the Q clock to CPU 1. RAM Error. Replaced the RAM at 2D. ROM 3 Error. Replaced the sound CPU and it booted to corrupt graphics and scratchy sounds. Replaced the socket on the 15xx and the sound PROM at 3M to fix the sound issues. Reseated the PAL at 4D and replaced the PROMs with leg issues at 3L and 4E on the video board to restore graphics. Graphics had sparkling issues. Replaced bad resistor pack at RM4 on the CPU board that has a lifted leg. Boardset suddenly died on the bench. Removed a jumper wire and reinstalled a missing 100 ohm resistor in the 6MHz clock line and replaced a bad 74LS32 at 1A on the video board to restore video. Boardset had an I/O 1 Error. Replaced a broken 2.2k resistor pack at RM13 to fix a floating input on one of the 56XX chips. The 4 RESET signal to both 56XX chips was stuck low. Patched a dead trace to pin 1 of the 74LS259 latch at 2M to finish the repair. Burned-in PCB.
-
Model: Tekken 3
Symptom: Dead
Reflowed the Program ROMs and tested. Bad power on sounds and missing blue on video output. Replaced bad transistor in the video output circuit and reflowed the Wave ROMs. Tested.
-
Model: Tekken 3
Symptom: Dead
Replaced smashed IC51. Reflowed IC52 and the Program RAMs. Reflowed IC03 and IC4. Tested.
-
Model: Tekken Tag
Symptom: Player 1 Left stuck on
Replaced bad 74HC257 IC and tested.
-
Model: Tekken Tag Tournament
Symptom: Dead. Stuck in watchdog
Board had nothing on screen but sync would be interrupted every few seconds indicating that the watchdog circuit was resetting the CPU trying to get it started. Verified ROM and Video PCBs were good. Checked over the main PCB for SMT soldering issues, cap damage, and other physical damage. None found. Removed the two TSSOP type 16Mb Flash ROM chips, cleaned their legs, erased / reprogrammed them, and resoldered them back onto the PCB. Tested.
-
Model: Super Pac Man
Symptom: Garbled sound then died
Reseated CPU and replaced bad 74LS257 at 3F and tested. Board failed during heat soak. Replaced bad 2K SRAM and 04xx custom. Tested.
-
Model: Mappy
Symptom: No audio
Replaced a 47uf cap, stuck volume control, and a bad LM4400 audio amplifier IC. Tested.