Mappy Broken Resistor please help verify

PrairieDillo

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I was pulling the chips off my Mappy (cleaning the leggs) to try to fix some artifacts around certain sprites and I pushed down on a resistor and cracked it in half so I cant measure it for its rating.

its in the B 1 section of this board
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Close up labeled C4???
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My old eyes read the resistor as Red Black Red Black Gold

On an online calculator it says 202 ohms
Can anyone confirm this?
 
In the manual it lists C-4 on the CPU board as .001 MF
 

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OK I am reading the specs on this like you guys are but obviously the broken part is a resistor. I should replace it with a ceramic cap? I mean its oddly clearly a resistor in there currently.
 
Just got home and looked at my board. It has the same as your board had at location C4
 

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Yes thats the same banding code also... Thanks for the confirmation

Now to scour old PCBs at work for a .001 mf cap
 
It should not be that hard. Do you not have a PCB at home that is dead and used for solder practice?
 

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Thanks for the help guys! The value was easy enough to find on a random old board at work.

20250611_203240.jpg

I managed to match a few axial cap values on the board also. Now to retest it when I get home.

I pulled all the eproms and mask roms as well as the 68k chips to clean the legs with contact cleaner and a fiberglass pen to polish the legs till they were shiny.

Mappy back up, cleaning helped fix the artifacts. Now if I can find that RAM module and reburn the HSS roms... With the credit jumper this machine would be done.
 
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I actually did find the unopened RAM module package (ordered from eBay) for the HSS. Now jus need to find two 2764 eproms so that I can burn the HSS ROMS and plop them in!!!!
 
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