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Mario Bros Repair Help

if I take out the N82S09N RAM
still the error is the same. What other type can I put in instead? From a test
 

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channelmaniac said:
OK... then check pins 7, 9, and 12 of the 74LS157 at 8M. What are they doing?

And do you have -5v connected to this board?
Click to expand...
Yes, -5V is connected and working on the pcb. At the beginning, I wrote that it was likely that +12V was connected to the -5V pin on the connector. That's why the sound amplifier IC burned out. That's why there's no sound now, but I'll deal with that later.
 
Ah... if the +12v was connected to the -5v then you need to check/replace 4P, 4R, 5P, 5R, 3R, 3P, 3S, and 3T as all of those run off of -5v.

I was having you work towards those as the signal from the 157 at 8M goes to 4S then on to 4R/5R.
 
unfortunately that's what I thought from the beginning. I don't know where I can get these parts from. There are many bad pcbs with many spare parts. I'll look it over. hm10422 I'm sure there isn't one. can it be replaced with something else?are you sure all ICs are dead on the -5V line?
 
channelmaniac said:
Well, you can take your oscilloscope and check the inputs vs. outputs of those and see... Don't use your logic probe on -5v logic.
Click to expand...
There is an analog oscilloscope, but unfortunately it does not work well and does not give an evaluable image. I'm getting a digital oscilloscope on Tuesday.
 
yes, I was also looking, but they don't deliver to Hungary.
I found 10124,10125 in Hungary, but 10422 is not cheap in the neighboring countries.
 
I purchased mc10125p, mc10124p IC. they behave interestingly. 4 MC10124 ICs in the pcb. I replaced (4R, 4P, 5R, 5P). no changes. however, when I changed the (3S,3T) MC 10125, only 2 colors alternated, approximately every 30 seconds. when I put the original MC10125l back, I got it back in the original faulty state. (MC10125l and MC10125P are so different?)
 

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You're quite welcome! I thought after you mentioned the bad hook up that all the ECL would've been toast. I don't know why Nintendo used ECL memory for Motion Sprite RAM, but they did.
 
Unfortunately, it hasn't fully recovered yet.
I noticed that 3R, 3P HM10422 ECL is heating up. After 10 minutes it heats up to 60C and starts causing graphic errors.
what else went wrong in the -5V circuit?
 

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Put heatsinks on them. They came with U shaped thick aluminum ones from the factory. Use thermal epoxy, but be VERY careful if you use electrically conductive epoxy to not get it on any pins.
 
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