More Diagnostics, Second Core, and More

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 I forgot to mention that Monday night we started running some of the "straight-8" diagnostics. We ran the following:

  • maindec-801-1
  • maindec-802
  • maindec-803
  • maindec-08-D03A
  • maindec-08-D04B
  • maindec-08-D07A
  • maindec-801-3A (closed MTTTY at lease two times, large file)
  • maindec-08-D0BA 

 All of these diagnostics ran correctly. This is odd because of the problems with FOCAL. We will continue running diagnostics to try and track down that issue. It could be that the Flip Chips aren't clean and properly seated. Some of them have been cleaned, but more need to be. 

 Tuesday we decided to try and get 8k of core running with one of the cores that Warren brought to test. We put the first one in and ran the 8k memory checkerboard program. It failed a lot of tests. We turned off the computer and then turned it on again to run again and it passed all the tests. Strange. We ran the test a few more times and it failed consistently on a few addresses. Warren thinks this is a tuning issue with the second core stack. Below is a (long) video of parts of this process. 

The serial cables are pretty much finished and one is braided.

All the bulbs are working now. The burnt out ones were replaced. These replacements are very similar to the original ones. The only difference is that they are a little looser of a fit. You can hardly tell that one of them was replaced! (In this picture the bulb 4 in from the left was replaced.)

The white bulb is the new replacement.

We decided to see how much power this machine actually takes. So, we made a video of this process. 

One of the G221 Flip Chips had writing on it. One of the ICs was circled and it said it was bad and needed replacement. We popped into Warrens Flip Chip tester and checked it out. It worked just fine so we put it back.


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