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I left out the page I referenced with a schematic. (The page is still there.) Everything to the right of his "C1" capacitor is what I'm describing; the stuff to the left is just for making a DC wall adapter to power it.

Deciding I needed a PWM for a project, I wanted to build my own to learn about electronics...so I went to radio shack and bought their $79.99 Electronics Learning Lab.(this kit alone is HOURS of amusement and learning)...but what I learned quickly is that following the Mimms book was very wasteful...the explanations of what is happening is scant...the diagrams are great, but blinking leds and making buzzer noises just ISN'T practical to a freshman in High School(I've taught them Freshman computing and mentored them in many aspects of I.T.)...

Below are some sites I've come across searching for 'simple enough for a basic solderer' and with readily available components(strip parts out of busted old computer power supplies/vcrs/radios/etc)..

http://www.electronics-lab.com/projects/audio/023/index.html

something fun and useful...a 'hearing aid' =) ... the entire site is useful

http://www.aaroncake.net/circuits/

some things more complex...

http://sci-toys.com/index.html

fun and educational .. some real easy stuff...and some more challenging stuff...

Hope this post ranks high enough for you to find it.

Since the dawn of the Automobile Revolution, automobile marques have been proactive in their approach to appeal to certain segments of society. By targeting these groups, automakers would find a much higher loyalty rate in an increasingly unloyal industry. Even today this tradition continues, with companies such as Toyota appealing to the youth market with its Scion brand, BMW and Mercedes appealing to the affluent market, Buick appealing to the understated senior market, and Subaru and Volvo appealing to the aging hippy market. One demographic spoken for by a large multinational automaker that often raises a bit of controversy, however, is the gay and lesbian market. It is within these confines that Honda finds its must staunch loyalists.

The connection stems much further than their not-so-subtle "H" logo. Since the inception of Honda by founder Kilimanjaro Honda in Tokyo, Japan in 1948, Honda has had a long line of successful industry firsts. Honda's first products imported to the United States were motorcycles capable of producing almost twice as much horsepower as their American brethren. Sold out of a small shop in San Francisco, their demographic was clear. From day one, Honda coined the term "Crotch Rocket" to target the gay and lesbian community. It wasn't long before Honda had made its first inroads in gaining market share in the vital west coast community.

While commercially successful, Honda didn't wish to fight a one-front war against Christians. In 1962, Honda started producing the HX100, their first entry into the area of gas powered lawn mowers. This allowed residents to show off their sexual preference to neighbors when not commuting. The new market, however, was something Honda was not experienced in, and proved to be initially unsuccessful. Honda faced several lawsuits alleging their lawnmowers oxidized almost instantly when mowing over damp grass.

It wasn't before long that founder Honda realized that the next battle would have to be fought in the ever-expanding industry of automobiles. In 1972, Honda began offering the United States its first car, the Honda Civic. While industry brass wanted to call it the "Civic Lesson," for the lesson it was trying to teach regarding the homosexual agenda, "Lesson" was eventually dropped from the title before release. Honda's experience in the lawn equipment market proved beneficial in their foray into automobiles, as the first generation of Civic Lessons were powered by their 49cc lawnmower engines producing a then-respectable 20 horsepower.

The response from the homosexual community was very positive, and sales of Civic Lessons matched other popular rivals in the west coast market from Toyota and AMC. Initial figures had pinned sales at achieving a 53% homosexual rate of buyers of Civic Lessons, a figure that has yet to be beat. The Civic Lesson proved to be a remarkable car for the homosexual market, as these families did not have any children and thus did not need room for a back seat. Honda foresaw new potential, however, with gay and lesbian

Okay okay okay, too many comments about guns.

Guns are not a reasonable solution for Yo Maing's problem. He/she specifically says "not looking for something that would get someone injured." Guns injure people. Besides, buying a gun and getting proper training just is not an interesting solution to the problem.

If you really want to do a security system on the cheap look into fish alarms like http://www.outdoorsweekly.com/ultrashackfishalarm. html

If you have one of those, you can set up a tripwire fence of barely visible fishing line around a piece of property so that when somebody or something trips it, a loud alarm goes off with flashing lights. You'll want to go with a non-nylon fishing line though because nylon stretches too much. My dad has used this system while camping in Alaska to ward off grizzlys and he's still alive too!

If $20 is still too much, you can make your own trip-wire circuit: http://www.aaroncake.net/circuits/alarm1.htm

++ Eschew Obfuscation ++

Can't remember the brand of cigarette, but their ads always featured some long legged model with the tagline "We've come a long way baby"

Using SSH and console is ok, when I just have to pop in really quick to edit some conf file, or tail -f some log. %80 of the time i'm doing this, it's pertaining to some clients web site i'm working on.

Guess what though? Do I fire up lynx to view my changes? Hell no! I use mozilla or IE, or some other html renderer. Do I create graphics or video from the console too? Hell no, I use some graphic program, with some nice gui, and pretty little icons everywhere BECAUSE I LIKE IT!!!!

Not only do I like it for that kind of work, I like it FAST! The faster the better!

Does it look like I care about leveraging old hardware for modern content? (shameless plug)

What I do use old equipment for is an ipcop firewall. I also use it to frankenstien together stepper motor interfaces because it IS old and I don't give a crap if it catches on fire because I wired something the wrong way.

Here's the whole wrapup to my post, i.e. the point. I read slashdot everyday, I build mosix clusters using plumpOS (couldn't remember the link sorry) My garage is filled from top to bottom with old computer crap because I know i'm not average joe sixpack user, and I will find a purpose for it even if it's just for research or fun. Average joe sixpack doesn't care about these things, he just wants his little clickety click icons to open up faster, or his OS to load quicker, or his games to run better.

And I sympathize with him %100. Thanks Joe sixpack for not taking the time to learn what I do, because I'm that car that stops outside your house to load up that PC you put out with your trash.

I know nothing about tcp/ip, but my electronics and basic are pretty good...

You'll need
3 analog dials
3 triacs
a parrelel port.

i'll just provide a link with some pertanent info. Basically wire up the triacs to the voltmeters (to isolate and backflow current from the VU meter's coils) and the other end to any data line on the parrellel port. Strobe the data line till your VU meters needle is pointing where you want it to go.

I know a lot of companies use Qbasic for stepper motor control.

here

I remember this one customer who had a PC based stepper motor controller running on a 8088 epson. (They used the machine for routing out a patterns in wood cabinets) Their sysadmin thought it would be a great idea to upgrade it to a 486, after which everthing broke. (well it still worked, but the timing for moving planks on/off the routing table, and cutting the actual design was totally screwed up)

After looking at the Qbasic code, I saw the original programmer did all their timing with for/next loops. AH HA! I said to myself. The faster machine made the loops run faster, thereby screwing up the timing. I just did a best guess and increased the delay in the loop, everything was happy after that.

Lately i've been rearing my ugly head at this page. The author has schematics for interfacing it to the LPT port, as well as software examples. I built my own interface using a rapid prototype board.

For those too scared to venture into building the interface themselves, I found this unit for less than $20 bucks from a company called ACS out in Florida. Unfortunately due to economic conditions, I cannot even afford that, but great looking product guys.

$500 is tooo much, i'd rather just interface steppers through the LPT and save an extra $380.

Lately i've been rearing my ugly head at this page. The author has schematics for interfacing it to the LPT port, as well as software examples. I built my own interface using a rapid prototype board.

For those too scared to venture into building the interface themselves, I found this unit for less than $20 bucks from a company called ACS out in Florida. Unfortunately due to economic conditions, I cannot even afford that, but great looking product guys.

$500 is tooo much, i'd rather just interface steppers through the LPT and save an extra $380.

Lately i've been rearing my ugly head at this page. The author has schematics for interfacing it to the LPT port, as well as software examples. I built my own interface using a rapid prototype board.

For those too scared to venture into building the interface themselves, I found this unit for less than $20 bucks from a company called ACS out in Florida. Unfortunately due to economic conditions, I cannot even afford that, but great looking product guys.

$500 is tooo much, i'd rather just interface steppers through the LPT and save an extra $380.

And with some carpentry skills, some basic soldering skills, and an I-PAC, and some parts you can have a very authentic feeling cabinet to play them in. Fun!

Oh yeah, make sure to finish like a piece of furniture (use expensive lumber) so your wife lets you keep it in the house...

You can easily make a Tesla coil if you have an old busted TV to rip apart. In general, the older and bigger the TV is, the better. And color TVs are better than black and white. This won't be a *great* Tesla coil, but it will throw a spark a few inches long and you can do all the standard Tesla coil tricks with it (St. Elmo's fire, etc.) without investing too much time or money.

Yank the flyback transformer out of the TV, and discard all its primary windings. Keep the big high voltage secondary winding (the one with the zillions of turns). It's usually encased in rubber and may look like a big rubber wheel. Its main lead has really thick insulation and connects to the side of the picture tube (where it looks like a stethoscope). The other lead (the ground) won't be as heavily insulated.

The only other parts you need are two NPN power transistors (2N3055), two 5W power resistors (20 ohm and 200 ohm), some wire, and a good supply of DC current (12-24 V). The circuit is a piece of cake. The first time I did it, I put the whole thing together with alligator clips.

This circuit has two primary windings around the flyback transformer core. The power winding is 8 turns, with a tap in the middle. The feedback winding is smaller (4 turns), also with a tap in the middle. The power winding leads connect to the collector leads on the transistors, with the center tap going to the +24 V DC power source. The feedback winding leads connect to the gate leads, with the center tap there going to +2-3 V DC (connect the resistors in series across the DC power to get the lower voltage in between). The emitter leads are grounded.
As current flows through one transistor, the changing field in the core induces a voltage in the feedback windings that turns that transistor off and the other one on. Then current flows the other way, and the same thing happens in reverse. So the circuit tunes itself to the proper frequency. But it also means that the first time you power it up you run a 50-50 chance of connecting the leads to the wrong transistor gates, in which case you get a stable DC circuit. So if it doesn't work the first time, try exchanging the gate leads.

This circuit is fairly well known, and doing a Google search for "flyback" and "Tesla" I found a schematic for it right away. The guy mentions on that page that the transistors get really hot and he is not kidding- they do. Don't leave it running for more than a minute without a heat sink. The RF noise generated by Tesla coils is incredible so expect to generate some interference. They make lots of smelly ozone. And if you let a spark go through paper, you can start a fire so be careful.

If you're lucky you can get 20-30 kV, which throws a purple spark a couple inches. (I only got about 4 kV out of mine- the spark was about a half inch long.) Pick up a neon bulb when you're at Radio Shack- these light up if they're around. The effect on a candle flame is interesting. Don't stick your bare finger near it because the spark does hurt if it hits unprotected skin. But if you hold a metal object and use that to touch it, you don't feel a thing (it's high frequency AC). Cool tricks include having sparks jump from the coil to a metal object in your hand, having sparks jump from a metal object in your other hand to ground (even a lousy ground), and having fluorescent tubes glow softly if you hold them in your other hand. If you touch one terminal of a fluorescent to ground then it will glow brightly between that end and the place you are holding it, like there are Orcs nearby.