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Someone is in need of your help
Hanilene Deticio
? "Maybelle C. Garcia" <mcgarcia@...> wrote: Date: Thu, 25 Oct 2001 18:26:03 +0700 Do You Yahoo!? Make a great connection at . |
Capator tester
Michael Carey
¿ªÔÆÌåÓýCould anybody point me in the right direction to
design a capacitor tester. I have studied Elec Eng, but am curious as to what
value to use as a resistive load as the basis (or should I use several?) I am
keen to put together something of this nature and am thinking along the lines of
using a PIC to do the work. Does anybody have experience in this area, and would
not mind discussing it.
Michael |
PIC resources
Michael Carey
¿ªÔÆÌåÓýHow many people have experience with PIC's, I am
looking to share code snippets with other people. Also if people have unique or
interesting projects using PIC's I would be interested in knowing of them. I
have my own PIC resource page - it generally deals with the Dick Smith PIC
programmer and testbed, here is the url:
If you have a webpage on a PIC project or resources
I would be interested in throwing in a link to it especially if it is a cool
project or has similar value.
Cheers Michael C
? |
Re: lcd display
purohit ranga
hi ,
okk want i really want is i want to use LCD display alphanumeric one to be used with a 8086 processor how can i do it and any one having the initialisation routine plz help me out. waiting for ur reply. sreeranga --- Jim Purcell <jpurcell@...> wrote: purohit,i want to use LCD with a auronomous system.You have my permission. :-) Seriously, I don't know __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. |
Re: Digest Number 134
d nixon
I do know that one of theAh, yes, the inventor of the dynamo. From: Jim Purcell <jpurcell@...> _________________________________________________________________ Get your FREE download of MSN Explorer at |
Re: Digest Number 134
d nixon
I'd like to know, myself, why people think that the charge is stored in the dielectric. It's stored on the plates, the dielectric just facilitates electron transfer.
-Mike From: "J. Pinkston" <pinkston@...> _________________________________________________________________ Get your FREE download of MSN Explorer at |
(No subject)
d nixon
Keep this nonsense to yourself. Some people here are actually against killing other people.
From: "ServoKamen" <kamen-san@...> _________________________________________________________________ Get your FREE download of MSN Explorer at |
Digest Number 135
Curtis Sakima
I know Jim ... I know.
It's just that ... I couldn't keep quiet. I just HAD to stand up and say "hey, wait a minute". In defense of all the many (true-meaning-of-the-word)(good people)"hackers" out there. Especially for the sake of the many "newbies" out there that are maybe ... unaware. That's all!! Thanks for your comments.... Curtis We can't blame the media people though, they gettheir information from whoever is said to know and if that person is a victim he will probably make it seem that damage is all hackers know how to do. Jim ===== * * * We guarantee hits to your website * * * * * __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. |
Re: Fw: communication concepts ??
angtengchat
¿ªÔÆÌåÓý?
|
all my freinds
helo
i m very thankfull to all of u for reply to my message "hacking" but i think that u can't understand me what i want. i just want to know "how it can happen" i don't want to do it my self i know its a very bad work. i just want to increase my knowledge. i appreciate all of my freind's advices which they give me about this and i hope that they will help me in future also. thanks to every body ejaz |
voltages and electrocution and electromagnetics
Mark Kinsler
There are a great many websites that are devoted to the proposition that radio waves can somehow be generated so as to provide an 'electromagnetic drive' to a spacecraft, but it unfortunately won't work. Electromagnetic waves won't drive a spacecraft anywhere. The E/M propulsion proponents claim that this isn't true, that The Government or the Illuminati or someone have perfected the technology and is concealing it from the world so that they can attain world domination or some damn fool thing.
Electrocutions for capital punishment in the United States are typically performed at voltages around 3,000 volts. The current is limited only by the resistance of the prisoner since a low-impedance transformer is used as a source. Electrodes are affixed to the head and one leg, salt water being used to maintain low resistance to the skin. Unconsciousness is instantaneous and death follows immediately afterwards. Despite the gory details that one sometimes hears about, the process is quiet, instantaneous, and presumably painless. Stun guns, ignition systems, and static electric generators produce voltages in excess of 10kV, but the power supplies of these devices have an extremely high internal resistance. Consider a 100kV source that contains an inherent one million ohm resistance in series with that source. Now connect a 500 ohm resistance across the leads of this source and calculate the voltage across the 500 ohm resistance. This low voltage is what you'll get across a human body. That million ohm resistance protects you, and it's why you don't die when you get a static shock from a rug on a dry day. M Kinsler 512 E Mulberry St. Lancaster, Ohio USA 740 687 6368 _________________________________________________________________ Get your FREE download of MSN Explorer at |
Re: tv to vga
Jim Purcell
ejazabidi,
Such a circuit would involve a great deal of circuitry. A tuner for yourDo you want your VGA monitor receive RF television signals (likeyes i want my vga monitor receive rf tv signals. will u help me to computer would be better. The circuit, even if it existed, would probably cost more than a TV set. Jim |
Radio waves
Mark Kinsler
When the amount of current through a wire changes, one radio wave is produced. If undisturbed by reflections, this wave propagates in a sphere, moving out from the wire that produced it at the speed of light. Periodic changes in the current through a wire will produce a train of waves. The frequency, phase, and amplitude of the waves in this train can be changed in order to send information on the wave train.
The wave itself results from the change in the magnetic field around the wire. As you'll recall, a change in magnetic field across a conductor results in a voltage across that conductor: this is how a generator works. The same thing happens in the free space that surrounds the varying magnetic field; i.e., a changing magnetic field results in a changing electric field in the same region. Now, we also know from our work with electromagnets that an electric field will drive current through a conductor and make it into an electromagnet. The same thing happens in the free space in which an electric field exists and is changing. Ergo, a changing electric field results in a changing magnetic field in the same region. Now look at those last two paragraphs. We've got a changing magnetic field-->changing electric field-->changing magnetic field. And of course it goes on and on, repeating forever. The important thing about this sequence of changing fields is the region of space where the magnetic and electric fields are changing. Everything we've said would indicate that the region of space that's near the wire with the varying current will contain the varying electric and magnetic fields. This is true, but there's more: the disturbance *propagates out from the wire*. A changing magnetic field generates a changing electric field a short distance out from the wire, and this generates a changing magnetic field some distance out further. This disturbance is the radio wave, and it travels at the speed of light. That's because it _is_ light, or the equivalent: light and radio and x-rays are all electromagnetic waves. Electromagnetic waves go through a vacuum for the same reason that a magnet or a static electric field works in a vacuum: the fields don't need a medium in which to operate. The easiest way to convince yourself that radio waves work is to tune an AM radio into a blank spot on the dial around 700kHz. Then start fooling with electrical stuff nearby. Flip the lights on and off, and you'll hear the signal in the radio. Or connect an inductor, a battery, and a couple of wires in series. Touch the wires together to make sparks, and listen to the radio crackle. With this arrangement, you could send digital code. If you worked quickly enough, you could send a list of numbers that would describe a picture or a sound waveform. This could be decoded by the receiver circuitry (one sort of computer or another) and the sound or picture reproduced accurately. That's how it works. M Kinsler 512 E Mulberry St. Lancaster, Ohio USA 740 687 6368 _________________________________________________________________ Get your FREE download of MSN Explorer at |
Re: Digest Number 135
Jim Purcell
Curtis,
A guy that EXPLORED and REVERSE ENGINEERED things likeExactly. Somewhere along the way, "hacker" got a bad (very bad)When I was young the only people could pick on were teen agers. When teen ager did something bad, like 'parking' or mischief, people got to use the term as though that's all they did. What if someone saw an auto mechanic trashing a car engine and someone asked who that was and the reply was, that's a mechanic. It's a stretch but if mechanics were a bit mysterious to the general public word could get out, Don't let a mechanic near your car, they trash engines. That's they way it happens I think. Just like ham radio operators used to get people angry at them when they caused radio or TV interference. The people didn't know about the other things hams did. And of course in that case the interference was usually not intentional. In fact most good hams worked hard to avoid causing interference and usually helped to solve the proem when they did cause any. Misunderstandings abound, mostly due to less than the whole story. We can't blame the media people though, they get their information from whoever is said to know and if that person is a victim he will probably make it seem that damage is all hackers know how to do. Jim |
Re: tv to vga
--- In Electronics_101@y..., "yahoo" <yahoo@c...> wrote:
channels 2-13) or just make a circut to convert NTSC video to VGA?i need a circuit which convert my monitor into tv receiver. helo yes i want my vga monitor receive rf tv signals. will u help me to find a circuit for that? thanx |
Re: newbie inquiry
angtengchat
toggle quoted message
Show quoted text
----- Original Message -----
From: "Mounir Shita" <mshita@...> To: <Electronics_101@...> Sent: Monday, October 29, 2001 9:01 AM Subject: [Electronics_101] Re: newbie inquiry Doesn't stunt guns produce about 5000 volt? That at least doesn'tFrom a biological point of view, a person can only withstand certain amount of current passing thru the body, beyond that he/ she dies of electrocution. To generate that amount of current, it all depends on the wattage and voltage as w= IV and I= V/R. To answer your question, 5KV will kill a person if it has the right amount of wattage to generate the amount of current based on ohms law. _________________________________________________________ Do You Yahoo!? Get your free @yahoo.com address at |
Digest Number 135
Curtis Sakima
Guys,
I just couldn't keep quiet about this one .... I've been doin' electronics since I was 'bout 9 or 10 years old. And I remember that when the term "hacker" first popped up ... what it kinda meant was like "a computer nerd" or "geek". A guy that really dug into computers. MORE than the average guy.... A guy that EXPLORED and REVERSE ENGINEERED things like BIOS code ... and "how a .exe executable really worked". A guy who wanted to learn it ... inside and out. A real hobbyist. Somewhere along the way, "hacker" got a bad (very bad) connotation. And it irks me, when people ... and the news media (etc, etc) keep on reinforcing that stereotype. Curtis --- "J. Pinkston" <pinkston@...> wrote: Not that I'm saying people should try to learn tohack but.... the part about hackers not giving up there secrets isn't necessarily true. There's an electronic book available for free D\L called "The Great Hacker Crackdown" ...... ---------edited for shorter length------- digital milenium copy right act you can get in alot of trouble....Message: 2 ===== * * * We guarantee hits to your website * * * * * __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. |
Re: Digest Number 135
Jim Purcell
J. Pinkston,
Not that I'm saying people should try to learn to hack but.... the partAs I say, Never say Never! :-) I have never had much sympathy for anyone who intentionally caused others wasted time or money or butted into their business. Hackers, the bad ones, do that. A hacker, I repeat is a lover of machines, sometimes computers. Some of them have too much time on their hands and not enough respect for others, so the hack into computers. Maybe the 'nerd' label applies and the just got teased too much when they were young and they therefore lost respect for others who did not respect them. Jim |
Re: Digest Number 134
Jim Purcell
"J. Pinkston",
Correct me if I'm wrong, but didn't Ben Franklin,I think Ben's only static generator was out of service when it wasn't raining. The first capacitors were called Leyden jars, I think that's the name of the town were they were invented. Even though I taught electronics for seventeen years we unfortunately had to skip over the wonderful stories of discovery that used to be part of such courses. They could be inspirational and spark (pardon the pun) the student's interest because they were about the real world. I can't even think of which country the town of Leyden is in. I do know that one of the showmen of electricity was a guy called Michael Faraday. I know he was a showman because the most often shows him in a very showmanship like pose. Anyway, the unit of capacitance was named after him, the Farad is one gigantic unit. The largest capacitor I've seen in terms of capacitance was in the hundreds of thousands of micro farads. Or say 0.1 to 0.2 Farads. Maybe it was because it was a static charge, like we get in the winter fromExactly, and a charge can only accumulate on/in an insulator. JimWhen I was reading your reply I saw the name at the end and said, Hey, I didn't say that. Jim |
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