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r67055

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This? Ohhh RAM..... No EPROM...
 

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Hammy

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7B only should be ok, 8 tests ok.

It maybe something nearby but try this first.
 

r67055

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Indeed, you need the SDIP type - the chip is the same but smaller.
Do you have that kind of RAM? I can't find a realistic price just in China which would take a lot of time to get to me. I would pay you!
 

Hammy

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Sure, PM me your address and i'll send you a couple when i get time ;)
 

r67055

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Sure, PM me your address and i'll send you a couple when i get time ;)
or should i take it out of this pcb? does not start
 

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Hammy

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WWF boot!

The problems with ripping from this board:

1: unknown condition ram, probably no good
2: 2nd hand ram anyway when the board was made (bootleg)

I'm happy to send tested good ram for free but it won't be quick ;)
You dumped the roms with no hesitation = true G and will be looked after!!
 

r67055

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Old favorite Double Dragon ....

If I don't put the jamma connector on it, the unloaded voltage is 5.29V, if I put on it 4.1V.
The voltage drops a lot, which indicates that something is short-circuited, a quick hint as to where the fault might be?
 

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stj

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if it drops a volt then the bad part is probably pretty warm!
 

r67055

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Old favorite Double Dragon ....

If I don't put the jamma connector on it, the unloaded voltage is 5.29V, if I put on it 4.1V.
The voltage drops a lot, which indicates that something is short-circuited, a quick hint as to where the fault might be?
In the meantime, it turned out that it is not the PCB that is short-circuited, but my power supply is weak.
I'm replacing
 
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