Psikyo Game Boards

[channelmaniac]

Fixed: Strikers 1945
Symptoms: Security Chip problem

Board would run through RAM/ROM self tests then freeze with a security chip error. Replaced the missing crystal on the security chip (unknown speed) with a 4MHz Crystal. Board booted but had garbled sound. Resoldered the Yamaha sound IC's crystal (Was soldered in by some ham fisted goon) to fix the sound issue and finish repairing the game.

[channelmaniac]

Model: Strikers 1999
Symptom: Player 2 would not move left

The R/C SIP filter was blown on the Player 2 Left input. Replaced it and tested the board. The 74HCT244 surface mount IC was stuck high on its input. Replaced the IC and played a couple of games.

[channelmaniac]

Model: Strikers 1999
Symptom: Repair Tip

When repairing the Strikers 1999 game board, the inputs are as follows:

Player 1 U/D/L/R goes through RC2 (Resistor/Capacitor network SIP)
Player 2 U/D/L/R goes through RC5

Player 1 controls (U/D/L/R and Button 1/2/3) go through U42 (74HCT244)
Player 2 controls (U/D/L/R and Button 1/2/3) go through U43 (74HCT244)

[channelmaniac]

Model: Strikers 1945
Symptom: Plays music on startup but nothing on screen.

Board would play an introductory jingle only. Would not play blind. A closer inspection revealed that one of the custom SMT IC had something sharp dragged across the pins which caused solder to dislodge and short all pins on one side and over half the pins on another side.

Resoldered the security chip & 2 custom SMT ICs. Checked the program EPROMs. They were either corrupt or unknown types as the checksums were not found doing a Google search. Erased the program EPROMs and reprogrammed them with the s1945.zip ROM set from MAME.

Played a few games to test.

[channelmaniac]

Model: Strikers 1945
Symptom: Dead

The PAL chip at U64 had a hole in the top of it. Copied the PAL chip programming from another board and replaced it. Board would then power up but had blank bars instead of normal graphics. Resoldered the ROMs at U20 and U21 to finish the repair and tested.

[channelmaniac]

Model: Strikers 1945
Symptom: Dead

Board was stuck in watchdog reset and had something on it between 2 RAM chips that damaged two traces. Patched the traces and resoldered the custom ICs. Board would then boot an run but had corrupt graphics. Checked the Graphics RAM. They were OK. A close inspection of the board revealed that the board was excessively flexed on one corner. Resoldered U1, U20, U21, U22, U23, and U34. Patched 3 traces between U20 and U21. The corrupt graphics were now solid blocks.

Another look at U20 revealed that pin 23 was broken at the body of the chip. Dremeled the body of the IC to reveal the metal trace inside and soldered a jumper wire to the pad to finish the repair.