Unfortunately I am facing major problems with my Sega Outrun (Upright)...
The game won't boot anymore after replacing IC95 (SN74ALS138AN)
I found out that pin 6 on IC95 was only 1.82VDC and did connect it to the VCC (pin 16, 5,25v) to make pin 6 a HIGH or 1.
I did this because according to the datasheet of the sn74als138an chip 2vdc is the minimum for a HIGH and 0.8vdc is the maximum for a LOW. It made pin 6 look suspicious.
Also according to the logic table pin 6 (G1) on low means that the outputs are not able to change at all.
Since the game stil doesn't boot after the repair... I am wondering if someone with a working Outrun cab can meassure the voltage (vdc) on IC95 from pin 6 (red probe) to pin 8 (black probe) and reply the answer so I can confirm that the 1.82vdc was wrong?
Question
Arcad3
Hi all,
Unfortunately I am facing major problems with my Sega Outrun (Upright)...
The game won't boot anymore after replacing IC95 (SN74ALS138AN)
I found out that pin 6 on IC95 was only 1.82VDC and did connect it to the VCC (pin 16, 5,25v) to make pin 6 a HIGH or 1.
I did this because according to the datasheet of the sn74als138an chip 2vdc is the minimum for a HIGH and 0.8vdc is the maximum for a LOW. It made pin 6 look suspicious.
Also according to the logic table pin 6 (G1) on low means that the outputs are not able to change at all.
Since the game stil doesn't boot after the repair... I am wondering if someone with a working Outrun cab can meassure the voltage (vdc) on IC95 from pin 6 (red probe) to pin 8 (black probe) and reply the answer so I can confirm that the 1.82vdc was wrong?
THANKS!
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