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Comment: A little history (Score 2) 79

by Gim Tom (#49364917) Attached to: SpaceX's New Combustion Technologies
Problems with injector design and combustion instability go back to to the Germans and the V2. They may have even been a problem for Goddard. The V2 engine is really a bunch of small combustion chambers at the top feeding into the main engine bell. I believe this was done, at least in part, to reduce the problems with combustion instability.

A much better and more efficient way to accurately simulate this process can really offer a lot in many areas, not just rocket engines.

Comment: Fond Memories (Score 4, Interesting) 88

by Gim Tom (#49356155) Attached to: Rebuilding the PDP-8 With a Raspberry Pi
My first "personal computer" was a PDP-8i at Georgia Tech in the late 1960's. The ISy school had one in a small room in the basement with an ASR TTY (33 I think). There was another room with at least one more TTY with punch and you would code on that machine and after signing up for time on the PDP-8i you would take your paper tape in and after toggling in the boot sequence and loading the BIN tape then the Assembler you would run your tape to punch out your assembled program to run on the machine. I may be leaving out a number of steps since that was a while back.

in any case that was my first taste of writing any code in a machines assembly language and even then I dreamed of having my very own PDP-8.

This is a cool project and even for an Old Man I can fully relate to why it was done. I think this experience led to a life long career working with computers ranging from Big Iron mainframes to PC's networks and a variety of internal and Internet facing Servers. Yes, even though retired, I have a couple of Arduinos and Raspberry Pi's around to play with! Learning new things has kept me going all these years.

Comment: What the Bongo Player said (Score 1) 366

This does, somehow, seem to be applicable.

Reality must take precedence over public relations, for nature cannot be fooled.
--- Richard P. Feynman

The experiment is in progress. Nature will give us the answer in time, but by then it will probably be too late do do anything about it if we don't like that answer.

Comment: DST should pay interest! (Score 1) 277

by Gim Tom (#49205131) Attached to: Daylight Saving Time Change On Sunday For N. America
My main gripe about the changes back and forth are when they occur. Early March is too early to Spring Forward, even down here in the south, and early November is too late to Fall Back. I am old enough to remember when we DID go DST all year. I think it was in 1973 during the first oil embargo, and the idea was to save energy. Not really sure how, or if, that worked at all. I do know that in central Ohio, where I was at the time, it stayed dark until pretty late in the morning, and everyone was talking about the kids at the bus stop at Zero Dark Thirty.

There have been studies that show an increase in traffic accidents during a period after the transition, and other studies that we are more refreshed if we wake up to a slowly increasing level of light in the morning. I know I do.

Now, since this is a SAVINGS plan we really need to get some interest on the savings. We could save all that daylight during the summer when we have plenty and get it back in the winter when we need it!

Comment: Hertz and Marconi beat them to it (Score 2) 88

Uh, The spark gap transmitters used by Hertz and Marconi were digital (Morse code is a digital protocol) and for the most part the only tuning was done by the antenna. Latter there was some sort of tank circuit or resonant tuning added, but I don't think so in the beginning.

Comment: Did the poster even READ the article? (Score 1) 681

by Gim Tom (#49109085) Attached to: Bill Nye Disses "Regular" Software Writers' Science Knowledge
I read the article in the link in this post and it seems to be a complete disconnect from the post. Did he even read it? I don't disagree with Nye at all and everyone needs to have some basic understanding of science or else everything the least bit technical in this world is just magic.

A decade or more ago I had a temp working for me who was a CS student at a nearby university. He was good at the routine stuff, but one question and his reason for it blew my mind. It had to do with how a change in our DNS server got to all the other DNS servers on the Internet in just a few hours. After some discussion on how this worked I realized that his primary misunderstanding was that he did not realize that the speed of light was a wee bit faster than the speed of sound.

Comment: Too Late for me DRM killed it a decade ago (Score 1) 450

I dumped Turbo Tax for a competitor when they used DRM at least a decade or more ago. I do my own taxes with TaxAct and have been using it since then. I am retired and have Social Security, some retirement income from a defined benefit plan that is still around and investment income. I could afford to hire a CPA or anyone else to do my taxes, but I don't want to. I use the process as an opportunity to review my investments and how they impact my taxes and make changes that benefit ME. As a retired engineer the way taxes are calculated drives me nuts, but what do you expect when Lawyers try to do math?

Comment: Don't just fix it --- Re-engineer it! (Score 1) 840

I have often spent more time and money repairing something when it would have been much easier and cheaper to replace it. I am 67 and from the generation just after the Great Depression and I guess I learned that sort of frugality, or perhaps now false frugality from them. However, my late wife used to lament that I never just fixed something I would redesign or re-engineer it. And, yes I am an engineer.

Comment: Re:Why not as civilians? (Score 2) 223

by Gim Tom (#48709029) Attached to: US Army Could Waive Combat Training For Hackers
I was in the USAF during Vietnam. I was never in Vietnam, but have the Vietnam service medal and credit for a Vietnam tour of duty. I worked on a computer system in Northern Thailand that monitored traffic on the Ho Chi Minh trail. The base was within rocket range of Laos and only about 75 miles from NORTH Vietnam. On base the only USAF personnel armed were the Air Force Security Police who, along with some other groups were responsible for Base security. HOWEVER, almost all of the USAF personnel, no matter what their technical skills, had a weapons card and there were armories around the base where we would draw weapons if needed. Depending on assignment there was even extra training in base defense. Even then everyone in uniform was expected to be able to defend the base if needed. THAT was the DIFFERENCE between those in uniform (which we were NOT allowed to wear off base -- the base was not officially there) and the civilian support personnel, and we had LOTS of civilian contractors since we had the largest computer system in that hemisphere and there was a crew IBM engineers on site to maintain it.

There were other USAF personnel who were support and technical that did go "over the river" to places we called Lima Sites. Look up Lima Site 85 and see if anyone really believes in the concept of a Non-Combatant in the military. Oh, and as for being stationed stateside when the NVA moved south in April of 1972 there were quite a few GI's who thought they would be in the states for their full tour of duty that suddenly found themselves in our tropical paradise within just a couple of days.

"Mach was the greatest intellectual fraud in the last ten years." "What about X?" "I said `intellectual'." ;login, 9/1990