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Author Topic: A fellow I, Robot collector could use some help  (Read 1668 times)
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DocRotCod
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« on: August 12, 2015, 09:23:56 pm »

Hello John and all, new to the forums here, but not new to the vids and pins.  I have been trying to revive my I, Robot and I too and a bad power supply (it worked up until a week ago).  Per your recommendation I ordered Ian's rebuild kit (great kit) and had a couple of questions if I may.

I went ahead and installed the 4 current diodes that you had skipped.  Did you ever find out the scoop from Ian on the difference between what was on the board and what was supplied with the kit?  Also, could you or anyone verify the marking on the board for the diode orientation are correct?  This would be cr21, cr22, cr23, and cr24.

Before installing the kit, I was getting the shutdown LED.  Then I installed all of the caps and tested.  Still had shutdown.  Then I replaced all the components.  Now I do not get shutdown, but I do not get any voltages to the monitor, pcb, etc.  It's like the game is totally dead.  I verified AC going to the in of the power supply, as well as the fuses.  I then reflowed all connectors.

At this point, I'm going to check for continuity on some of the places I soldered components, but was hoping to pick your brain(s) and see what you think.

Thanks!

Thomas
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iankellogg
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« Reply #1 on: August 13, 2015, 08:08:55 am »

I can try to figure out the orientation but I don't have much to go on.

If you still don't have any voltage There are a few things you can try.

Make sure you are getting +12V out of the 7812 IC. there are pretty much no test points so if needed I can try to tell you exactly what to probe when I can get access to the schematic later.


If the +12V is good I am going to assume that the controller IC has died. that is one I have not included in the kit (as I didn't source them yet at the time, work in progress thing).

If you are willing to send me the board I would love to fix it for you so I can have a board on hand to finish the rebuild kit and instructions/take photos.
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DocRotCod
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« Reply #2 on: August 13, 2015, 09:51:06 am »

Ian,

I would love to send you the board, sounds like a fair trade-off.  Let me check a few things first then if I don't get it resolved I will send it your way.

Thanks for the help!

Thomas
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