John's Arcade Forum - Classic Arcade and Pinball Collecting and Restoring Discussion Forum - RETRO MAME - Nintendo Vs Forum
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Author Topic: DK video issue.  (Read 268 times)
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johnrt
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« on: January 09, 2018, 11:58:21 AM »

Hi! I have an issue with one of my DK boards. This video shows the issue. It's 100% sure it's on the video PCB and it's not a ROM or PROM issue (I've swapped boards and ROMs to make sure). So has anyone seen this before, and can guide me in the right direction?

https://www.youtube.com/watch?v=pqZ_otZzdAU
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johnrt
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« Reply #1 on: January 10, 2018, 04:45:10 PM »

Using a logic probe I found that one of the outputs on the LS283 at 7R was stuck high. Changing this IC fixed this issue!  Cheesy
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