Re: [TUHS] Joe Condon [ long, slightly off-topic post ]

So as part of my attempt to remember the names of the folks with who I worked I just read Joe's wikipedia page which doesn't seem accurate to me. If this is too off topic let me know. The page says that Joe "was exposed to UNIX on the Honeywell 516 machines in the early 1970s." This seems wrong to me. We did have a 516, but it ran an experimental virtual memory system called 516-TSS. I lived on this system and still have some of the octal instruction opcodes burned into my brain-ROM. I seem to recall that the department got a PDP-11/40 that ran UNIX version 3 in maybe the summer of 1972 which I used for writing up the documentation for my project. The page also says that "Condon and Ken Thompson promoted the use of the C programming language for AT&T’s switching system control programs. Condon acquired a small AT&T PBX (telephone switch) that handled about 50 phones; he made the necessary hardware changes and Thompson wrote the necessary software programs. The PBX code rewrite in C was a success and hastened the adoption of C for all switching system software within AT&T." This also doesn't match my recollection. One of the big projects in the department was what I think was called SS1 for Slave Switch 1, which was an all-digital telephone exchange. It replaced some other monstrosity whose details I can't recall except that Joe and Dave Weller signed the appropriate paperwork allowing me to take a good portion of it home when it was decommissioned giving me a huge stock of Augat wirewrap boards and 7400-series parts. The SS1 was originally going to use LSI-11s but the stupid way in which DEC implemented the DRAM refresh made that impossible. I think that the final thing used a couple of PDP-10s. As part of being all-digital it used the digital filter work by Jim Kaiser and Hal Alles. I do remember going into Carl Christensen's office to ask him a question and found him staring at a huge C listing; it turns out that a bug in the code had caused SS1 to send KP pulses without their corresponding ST pulses with the result that every single keypulse sender in the Berkeley Heights telephone exchange was taken off line and needed to be manually reset to restore long distance service. They were not happy. Anyway, unless there was something that happened later after I was gone, I'm thinking that the wikipedia page is incorrect and that this PBX was built, not acquired. It was, as far as I know, the first use of C to control machinery. It's actually because of this machine that I'm trying to track down the name of some folks from down at the end of the hall. I have strong memories of the Bell System exhibit at the '64 World's Fair, especially the booth where one could go and talk and they had bar graphs on a monitor showing the spectrum of your speech and could mess with it. Many years later, while waiting for some deck of cards to finish loading, I poked my head into the lab down the hall to see what they were doing in there, and noticed polaroid photos of that exhibit featuring the guys in the lab. Once they stopped telling stories from the World's Fair, they taught me a lesson about systems engineering that opened my eyes. They were developing a circuit that replaced the pound of iron hybrid transformers that were on every telephone line with a small toroid and an op-amp. Their circuit would sense when the iron was getting close to saturation and run current through an additional winding to keep it in the linear region. While that circuit cost a lot more than a hybrid transformer, it paid for itself by reducing the amount of concrete needed to build telephone exchanges. Would love to know who these guys were which is why an org chart would help. And maybe someone out there like Ken can help me out with the accurate history. Jon