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Comment: Re:Antennas (Score 1) 183 183

I built a 2 meter gamma match using a piston trimmer capacitor and brass tubing to slide over 1/8" brass rod like a trombone. I used it to load up things like fences and high voltage transmission towers on transmitter hunts.

I have a large loop antenna with a four gang trombone cap hanging from the roof of my garage. I really gotta finish that thing one of these days.

Comment: Re:A DIY Expansion Cartridge for a C-64 (Score 0) 183 183

Oh jesus christ would you just fuck off and stop trying to turn every thread into some sort of bizarre political grandstanding about gender issues? Are you some kind of SJW or something?

Says the person so obsessed with the gender wars that he takes a statement that not once mentions gender, and turns it into a sex based profaity rant. Likewise, he misses the main point for his umbrage and high dudgeon

And your sad story of the person who was not encouraged is just that. A person who wasn't encouraged. That woman's parents were complete jerks. Parents are that way some times.

I certainly was actively discouraged from a science career, Parental units wanted me to be a priest, and when my older sister decided to drop out of college with only one semester left, they took it out on me, refusing to give me any assistance at all. Really weird, and in retrospect, I guess that since she was groomed from a young age as the smart one, and I was the jerk always breaking things and annoying everyone, it was terribly upsetting for them.

She settled into a lifetime of minimum wage jobs, while I became a professional on my own. I haven't lost my great capacity to get on people's nerves though.

But sad stories abound, and mine is just one more, not too dissimilar to your friend's. I knew what I wanted to do with my life, and I did it. To allow others to dissuade you from your passions is you giving them power they don't really have. It's nice to have supportive family, but by no means mandatory.

Now try telling me that all you have to have is "passion" and that society has no bearing on how one grows up.

Perhaps some folks mistake passing interest for passion. Perhaps some cannot experience passion at all. Perhaps some of us are immune to "societies" approval or disapproval. I only speak from experience, and the experience of colleagues and friends. Of course that is a limited set, one that includes males and females, those who were encouraged, and those who were not. Made no difference to them - they were working their passion.

But there is one thing that is not debatable. If you allow others to dictate what you do in life, you are placing their dictates above your interests.

Comment: Re:Huh (Score 1) 223 223

If you molest my daughter, you'd be lucky to be living under a bridge. It'd make it harder for me to find you, but eventually....

You know, that's about the oddest - and disturbing response I've heard to a statement like the one I made..

Short answer, I have no intention of molesting your's or anyone else's daughter. Why you would take anything like that from what I wrote is a puzzlement.

1. I would be a bit concerned about your overcompensation .

2. And online threats of violence are never encouraged. Just a friendly reminder.

Comment: Re:The Apollo Engine (Score 1) 48 48

WHICH one?

Yeah, you figure in an earth to LEO vehicle that we'd be talking about a J2, or one of the LEM engines? Of course he's referring to the F1 engines.

Perhaps I need to explain here my dowmoddingest friends.

The J2 engine was not designed to be run at ground level. It's thrust nozzle was designed to run at altitude, with it's 27.5:1 expansion area ratio That's wide, and not efficient at sea level. In contrast, the F1 has a 16 to 1 ratio. Much more suited to lower altitude work. It's all related to the external pressure the rocket faces. Here's a pretty good explanation.

Anyone look at the ill fated Spacex launch? before it self disassembled, it was operating in an area beyond it's most efficient operation. You could see the much wider expansion of th exhaust.

Ideally, a rocket motor would adjust the throat to exhaust ratio for best efficiency, but that would be too expensive. Probably very heavy, and possibly complicated.

The J2 is designed to be restarted also.

There were some other engines on the Saturn V rockets also. The Aux Propulsion System or APS, provided roll control while using the J-2 engines. The APS used a single SE 7-1 engine, and three TR-204. engines. They were hypergolic engines. Here's a nice descriptive page:

So while the fellow who asaked the original question gets downmodded to 1, the caffeine fueled maniac who thinks he knows all about Rocket engines, is modded up to three. I'm catching a couple downmods to 0.

Anyone want to accept the challenge of explaning why anyone who obviously didn't know a lot about the Saturn would be referring to the J2 or APS engines - obvious specialty engines, and the rager who missed four of the engines on the Saturn V is modded as insightful?

Or does missing over half the engines on a rocket while acting like an expert qualify one as insighful on slashdot these days?

Comment: Re:A DIY Expansion Cartridge for a C-64 (Score 2) 183 183

I do miss those days, literally spent in my parents basement, or at my friends place in the attic, listening to late night radio while hacking away.

Hell yeah! I've always thought the metric for a person thinking about getting into computers was exactly this sort of thing. Under represented groups should know that you have to have that sort of passion for it. The pays not so good, the hours suck, there's almost zero respect, so you gotta have that passion, when digging into to something for fun - is fun.

Comment: Re:Something I won't put on my resume (Score 3, Insightful) 183 183

I think I'd have been tempted to tell him that he knows how to fix it if he knows how to whistle. Of course, a lot depends on his personality; if he's an arrogant stuffed shirt, you'll be looking for your next job before you know what's happened.

If he's at all human, you'll end up being indispensable. A bos who fires you for pulling his ass out of a hot frying pan is no person to work for.

I was known for some wild seat of the pants fixes. My suits appreciated it - a lot. It's startling when a room of 7 figure folks applaud you after you bring a computer system back to life. And the weirder the fix the better the stories later. Versatility is a plus.

Comment: Re:The Apollo Engine (Score 0) 48 48

Amazing they let it languish for solid boosters.

Nothing amazing about it. Had to do with the ICBMs. They needed to pour money into that research without being too obvious.

ICBMs and solid boosters is because of readiness. Liquid fuel you have a limited window and time to get read. Solid can sit for much much longer.

So the concept of abandoning your Lexus for a Dodge Caravan then.

Comment: Re:The Apollo Engine (Score 1) 48 48

Occam's razor. We're talking about launch vehicles, and the big kid on the block is the simplest answer, and since he didn't say - "No I mean the second stage', or "Apollo hypergolic engines, It's a real safe bet he meant the big kahuna F1 motor.

IIRC, the maneuvering engines are still in production in some form, so rebuilding them would be redundant.

Comment: Re: It's that time... (Score 1) 318 318

What we call industrial "robots" really are just fancy remote control/programmed toys. They got slightly more smarts than a woodchipper. They follow a programmed dance --rather stupidly. If something is between them and the next step they go THRU it with 500-1000lbs of force.

And isn't that the hell of it. We have self driving cars, radar based braking and road centering assist but can't put sensors on a construction robot that will inform it that something is in a place where it shouldn't be. Time to move past the silly "programmed dance" mode. It isn't rocket surgery, isn'at all that expensive, and should be considered a distinct legal liability for the companies that produce and program the things.

The UNIX philosophy basically involves giving you enough rope to hang yourself. And then a couple of feet more, just to be sure.