Flip Chip Testing Progress

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A quick update on our FC testing project. 

We are about 2/3 of the way through testing all the flip chips that are currently testable with Warren's tester. We have approximately five columns left to test in the bottom half of the backplane. Previously I reported that we had a failing 103, and two failing 216s. 

After I asked Vince and Michael to help me understand how to interpret the errors from the tester, and and they consulted DEC documentation, they realized that the test for the 103 had a bug. Vince updated the test vectors and tested one of his 103s, and it worked. I got the fix to the M103 test, and that solved that problem. Today, one of my students and I tested a bunch of chips in the first column of the lower half. Shortly after I left, he discovered an M617 that fails. 

So, there's another one to fix. But honestly, I love getting news like this, because these are all fixable things, and once they're fixed the machine should be much more functional and reliable. 

As always much thanks to Vince and Michael for their invaluable help and mentorship.

In other news, we started a PDP-12 Roll Call thread on the VCF forums to try to track all known PDP-12s. That should be fun.

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