Engineering

hi, anyone knows if the dielectric constant for materials are fixed for all frequenies??

If a rotating A-band radar (i.e. Spoon Rest) were placed in the field with a receiver tuned to the radar's frequency, could one detect the presence of both the radar unit and the listening receiver with a directional antenna?

Is there sucha thing as a pressure increasing valve? If so, depending on the PSI put into the "low" side.. how much of an increase in pressure would it be.. I know that there are alot of things to take into account.. Lets say on the "low" side, we have 200-500 PSI... is there any way of doubling that with a valve ( if ther is such a thing )?? thanks

Ignore how little application this may have in modern times but i have an idea. Say you are sailing your ship somewhere where there isn't much wind. Could you create artificial wind by using a system of bellows (obviously they'd have to be large, and have some well ordered and fairly strong mechanical power source)---- or would that not get you anywwhere because the air would push the bellows back with equal force as the masts are pushing the ship forward? Would the forces just counter each other with the bellows attached the very thing they attempt to will?

This is a reply to the Remote Control post thing. It was closed for some reson. You know, I could break into area 51 personoly if I had the equipment. I can get the information easilly enough on the securoty perimeters. I have two uncles,(whos names I will not tell so as to keep them safe,) who work for the goverment. One who creates the gov.'s securaty programs, and another who runs them, and teaches thse to use them. If I could get those to talk, I could come up with a why to brake in side, disable the security, and get all the info. I need to keep the internet conspiracyers going for a while. The problem is, I'm poor as dirt, and can't afford the equipment, and I live …

Wow nobody posts in this section very often. Well here is my big engineering feat---- and I think it could possibly be not very expensive. OK, finding Area 51 is not difficult, just look up the road, and drive down it until you get to the sign that says lethal force will be used against tresspassers. Well I think i got a way to get past the sign---- remote control. Obviosly simple radio wont suffice, because there's probably no safe or legal place to get close enough range----- so what about remote control by satellite? I am definately not buying a satellite- so what if you could adapt existing equiptment to do a different function? OK this likely nee…

Hi everyone, I have a problem at the moment with a PWM Controller (IC) uc3844 and I am wondering if anyone out there has any experience with them. I am using it in a Flyback converter Power supply circuit to switch a Mosfet but I am having great difficulty getting it to switch. it seems that the Voltage feed back is getting 2.5V which is max through the chip but it is meant to be an input not an output. i think that the Error amp inside is fried but any help on the situation would be greatly appericated Cheers, MD :confused:

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - This is SDR-4X, the newest robot from Sony. Sony's last robot was Aibo, the robotic pet-dog. What this little thing can do is pretty amazing, I want one. Too bad it costs as much as a luxury car... TOKYO (Reuters) - Judging from the cooing at a demonstration of Sony's diminutive SDR robot, few would dispute just how cute the humanoid machine is. Its creator Masahiro Fujita, who called it "him" instead of "it", seemed to feel genuinely guilty as he pushed it over to show how easily it gets back up. "I don't like this," he said. But while Sony, the world's largest consumer electronics maker, may have su…

Here my idea for an amp. An amplifier about 80 to 100watt RMS made of quaility amplification technology preferably valve, combo. Equipped as part of the amp or as a seperate package. A sine wave invertor and about 2 to 4 to 6+ hour current supply parralel wired battery cells. Also integrated with a charger for auto-charging when in AC 240V mains. All these parts are off the self, a seperate package minus the amp could probably fuel a 4 piece band. 2-4-6+ hours continuous. So get out your Jungle boogie cuz, we're gonna have a party. What do you think?

I've been working on an idea that an empty universe needs energy to sustain itself. To have three infinite dimensions of empty space, eg. pre big bang, would take energy to keep from collapsing into a non-point. I need a device to make some measurements to prove it. First a question. If I take a piston in a cylinder sleeve with perfect ring seals into the vacuum of space, can I pull the piston down in the cylinder creating a vacuum as large as I want and let go without the piston being pushed back because the pressures should be equal on top and bottom? Just aman

I've been playing around with ideas on how to find natural mediums on Earth that might record sound as a way to hear into the past. Since T Edison made a device that cut a uniform growing groove that in the presence of sound, incorporated the sound in the groove, then other natural growing mediums might incorporate sound as they grow at a speed and size compatable with sound freq. One idea might be to see if a human hair which grows continuously lays down its structure as it hardens near the root with sound incorporated which might be read with an electron microscope. Sample hairs could be calibrated with sounds and entered into a data base. Sound through the skull…

Has anyone seen the new designs for the world trade center? in my opinion, they both look like crap. especially the one that looks like plain glass. if it was up to me, i would have just kept the original design of the first world trade center, but would have made the skyscrapers larger. i-m out:bs:

I'm hoping this is the right forum for my question. I was reading that a VCR broadcasts the signal from the tape to the TV. If this is the case, what prevents two TVs in adjacent rooms running tapes from getting their signals scrambled, or one picking up the other's movie?

There is a new research on the ways people walk. With this method, they can tell who anyone is, just by the way the person walks. Here is a few quotes, and an external resource. "When a person walks, body parts — the legs, knee joints, arms, elbows, and so on — create a particular repeating pattern as they each move through space. The video camera captures these points of movements and sends them to a computer for analysis. The computer notes the movements and establishes mathematical relationships for each point to create the "signature" patterns it needs to recognize for each individual." http://www.abcnews.go.com/sections/scitech/CuttingEdge/cuttingedge021025…

Back in '83 at Rockwell I had a 32 lead logic analyzer for diagnosing bad boards. It had a resolution of 5 nanoseconds. I could see PAL inputs and outputs and logic chips and even had clips for the microproccessors. Often trouble was just a short between two pins or a solder void on one. The tool was invaluable and it was from HP for 50 grand. Whats available now and what kind of resolution are you getting? Just curious. Just aman