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self-tuning portable RF jammer http://www.ladyada.net/make/wa...

Why can't Iphone / ipad have usb port for charging and not high priced apple changes

The Apple chargers just supply a USB port power. The iOS devices can all plug into any USB port to charge...

-1, wrong.

From Ken Shirrif's blog:

"The USB output also has specific resistances connected to the data pins to indicate to the iPhone how much current the charger can supply, through a proprietary Apple protocol.[10] An iPhone displays the message "Charging is not supported with this accessory" if the charger has the wrong resistances here. "

[10] Apple indicates the charger type through a proprietary technique of resistances on the USB D+ and D- pins. For details on USB charging protocols, see my earlier references.

[14] Ladyada reverse-engineered Apple chargers to determine how the voltages on the USB D+ and D- pins controls the charging current. Minty Boost: The mysteries of Apple device charging. Also of note is the picture of the internals of a official Apple iPhone 3Gs charger, which is somewhat more complex than the charger I disassembled, using two circuit boards.

Here is some detail on what Apple did: http://www.ladyada.net/make/mintyboost/icharge.html

The standard way of signalling that 1A is available is to tie D+ and D- together. This is part of the USB spec. Apple went their own way so that iDevices would only draw 0.5A from these chargers. Only an Apple charger will deliver 1A to them.

Later on Apple changed this so that their devices were compatible with 1A chargers, but only because they introduced a 2A charger and new DRM system that requires comms with the chargers.

Essentially the policy has always been to tolerate generic USB chargers, as mandated by EU law, but not to allow them to charge at maximum speed even if they are capable of delivering 2A. Naturally other manufacturers quickly figure out how to work around the DRM, hence you can buy unlicenced 2A chargers, but every now and then Apple rolls out a new firmware update to break them. It's a bit like the jailbreaking situation - you know your efforts will be defeated so you don't reveal all your tricks at once.

http://www.xgamestation.com/

http://www.ladyada.net/make/fuzebox/

This is a fantastic mathematical, programming, and home creation project which you can do with your son. Its a great teaching tool, and looks awesome once your done. Take a look! The best part is that its relatively cheap as well.

http://www.ladyada.net/make/conway/

It's the way Apple uses the connector to extract money from you. With the original dock connector they kept changing the USB charger in subtle ways to break third party cables and chargers. Some of it is detailed here.

So they force you to buy expensive Apple products. To be fair Dell and HP also tried to jump on that bandwagon by making their high end model laptops refuse to work with generic chargers, but Apple does it with everything.

There is also the annoyance of not being able to just hook up your device for a charge or to copy some data at a friends house unless you brought a cable, and even then you need iTunes and it won't let you copy some stuff off the device. USB isn't perfect but it really is universal.

Battery charge / discharge rate is not constant over the charge level of the battery. The percentage reported by the battery to the OS is just the voltage reading, which is not truly linear to the actual charge level. It even depends on the load being placed on the battery. See this image (from here).

So sure, you can do a bad job of reporting remaining battery time that way. Or you can do a good job by involving some more advanced mathematics. This is a good example of why math is useful, even if most jobs don't fundamentally require it. Most programmers I know would look at the above chart and declare they have no idea how to deal with that, but it is pretty close to linear, and they know how to write that math, so that's what they'd write, then call it good enough.

You can be a programmer without higher math. But you can be a better programmer with it.

Battery charge / discharge rate is not constant over the charge level of the battery. The percentage reported by the battery to the OS is just the voltage reading, which is not truly linear to the actual charge level. It even depends on the load being placed on the battery. See this image (from here).

So sure, you can do a bad job of reporting remaining battery time that way. Or you can do a good job by involving some more advanced mathematics. This is a good example of why math is useful, even if most jobs don't fundamentally require it. Most programmers I know would look at the above chart and declare they have no idea how to deal with that, but it is pretty close to linear, and they know how to write that math, so that's what they'd write, then call it good enough.

You can be a programmer without higher math. But you can be a better programmer with it.

Normally, no - you either get your choice of a board that's shaped like a standard Arduino and can support the Arduino shields, or else a board (such as the Teensy or Really Bare Bones Board) that's narrower and has all the pins on 1/10" spacing so it can plug directly into a standard breadboard, leaving you room to connect it to other things. While most of the Arduino connectors are on 1/10" spacing, a few of them are offset for historical backward compatibility reasons.

I saw designs on Limor fried's Site years ago that she made for her thesis I believe. It's a good read. Either way it's funny how long these things took to become popular
http://www.ladyada.net/make/wavebubble/index.html

TFL for anyone who can't google

Its funny YOU think they took that long to become popular, Jammers were readily available $100 on Dealextreme the day ladyada jammer project got posted (years ago).

I saw designs on Limor fried's Site years ago that she made for her thesis I believe. It's a good read. Either way it's funny how long these things took to become popular http://www.ladyada.net/make/wavebubble/index.html TFL for anyone who can't google

Article 1: Is The Philly Cellphone Jammer A Hero Or A Jerk?
Article 2: FCC Wants To Know If It Sometimes Might Be Okay To Jam Cellphones In Interest Of Public Safety
Article 3: FDA Adds Diabetes & Memory Loss Warnings To Statins
Article 4: Chase Plans On Caring Even Less About Customers With Less Than $100K In The Bank
----
Oops, did I intend to post this link?:
* http://www.ladyada.net/make/wavebubble/

The world may never know...

Article 1: Is The Philly Cellphone Jammer A Hero Or A Jerk?
By Chris Morran on March 1, 2012 12:15 PM

# http://consumerist.com/2012/03/is-the-philly-cellphone-jammer-a-hero-or-a-jerk.html

"A man in Philadelphia decided he'd had enough with listening to his fellow bus passengers blab away on their cellphones. But instead of buying himself some noise-cancelling headphones or politely asking people to pipe down, he chose to fight back with a handheld device that jams their signals.

"I guess I'm taking the law into my own hands," he told NBC10, which caught him red-handed with the illegal jammer, "and quite frankly, I'm proud of it."

Those who ride the bus with the man say he should be ashamed, not proud.

"How dare you decide that I can't speak to somebody or I can't use my cellphone?" asks one passenger who spotted the man using the jammer on her way to work. "He's blatantly holding this device that looks like a walkie-talkie with four very thick antennae. I started to watch him and any time somebody started talking on the phone, he would start pressing the button on the side of the device."

Experts tell NBC10 that there is a good reason the FCC has made it illegal to jam cellphone signals: "With cellphone jammers you are limiting all types of communication tools that use the radio frequencies. You have the potential to cause a public safety disaster. Cutting off communication by not only our public officials to their dispatch centers but also cutting off the public's communication to 911 can be a dangerous thing."

When confronted by a reporter about the illegality of the device, the jamming gent said he believed it was "more of a gray area," but hours later contacted NBC10 to say that after further research he would get rid of the jammer." (Article includes video not linked here)

* View more videos at: http://nbcphiladelphia.com/
* http://www.nbcphiladelphia.com/news/local/Rider-Annoyed-by-Calls-Jams-Phones-on-Septa-Bus-140966733.html

© 2005-2010 Consumer Media LLC except where noted.
--
Article 2: FCC Wants To Know If It Sometimes Might Be Okay To
Jam Cellphones In Interest Of Public Safety
By Chris Morran on March 2, 2012 3:30 PM

"Chief among the reasons given by the Federal Communications Commission for outlawing the practice of using signal-jamming devices for cellphones is public safety. With 70% of 911 calls now made on wireless devices, the FCC has argued that deliberately blocking cell signals could put people at risk. That being said, the agency is now willing to hear from people who think it might occasionally be in the public interest to jam wireless signals.

"While the important function that wireless service plays in protecting public safety is undisputed, some commentators, including some law enforcement personnel, have raised concerns that wireless networks can be used in way that put the public's safety at risk," writes the FCC in its notice to seek public comment on the matter.

Those in favor of the selectiv

Apple has made it increasingly hard to charge one of their devices without an Apple charger (see http://www.ladyada.net/make/mintyboost/icharge.html). Once they get a hold of this it will mean that all iDevices will only chage with authenticated Apple chargers.

It is just as shame that two other important initiatives, namely forcing manufacturers to standardise on USB micro/mini for charging and allow batteries to be replaced and removed for disposal, seem to have stalled.

Stalled where? From my own observation, every non Apple manufactured gadget(*) released within the last 2 years uses USB for charging, and you can freely interchange chargers and USB cables.

* - Apple uses a non standard way to charge the iPhone, so it won't work with anything but an Apple blessed charger.

iOS isn't about locking you into Apple's services. The services are about adding value to the hardware

Apple is fairly unique in that it makes money from both the hardware and software sides of things, but iOS is definitely designed to make you a part of their revenue stream. There is a reason you can only install apps from the App Store, and why you can't just copy files to it but have to instead sync them with iTunes. It drives you to their services, and as any retailer will tell you just getting people through the door is half the battle.

There is a reason they use proprietary dock connectors instead of the standard USB that almost all other device manufacturers do. It locks out other companies unless they are willing to pay Apple to license the technology, and even then it doesn't guarantee compatibility with the next version. Have a read of this page which describes in detail how Apple kept breaking 3rd party chargers with every hardware revision.

Another similarity is that once you have bought apps and DRM protected media you have to keep buying Apple/Amazon products to use it. One of the nice thing about Android and WP7 is that you have a wide choice of devices, which is I think a major factor in people's dissatisfaction with the Fire. They see it as an Android device, but Amazon removed many of the freedoms you expect from one. Wikipedia is right to call it a fork of the main codebase.

My understanding is that you still need to plug the USB end somewhere to power it. So you need either a USB extension cable, or an HDMI extension cable.

Or something like this :)

No, the connectors that interface with the PC are standard USB or Firewire.

One end of the cable may be, but the charger uses resistors on the USB data lines to prevent third party chargers from fast charging. Here is a detailed analysis: http://www.ladyada.net/make/mintyboost/icharge.html . Note that most devices will fast charge by detecting the standard method of simply connecting the two data lines together.

Also the other end of the cable has a non-standard Apple dock connector. Apple locks out third party devices that use it, even officially sanctioned ones. People who bought expensive speakers or car head units with a dock connector found that a generation or two down the line iPods no longer worked with them.

You are NOT required to use iTunes either.

Except that Apple actively tries to lock out third party software so if you don't use iTunes you will end up not being able to load files onto your device until someone figures out a work-around. For example the current iTunes database file was encrypted years ago and it look months for a fix to appear.

Apparently, it now comes with reversi!
What an incredible deal!

If only he have done a cross breeding with his Minty MP3 player, it could be one step further to this goal.

Imagine how today's racer bots would be absolutely lost without the wireless heart rate details, power meter details, derailleurs and race radios to get detailed instructions play by play instructions from the boss. If wireless brakes were in the mix.... it might not be funny. Although it would separate the guys who rely on brakes and the guys like Hinault (if any still exist) who keep theirs adjusted so the brake pads barely touch the rims until the levers meet the bars.

Lady Ada has a cool RF Jammer that fits in a cigarette box that I've always thought would be fun to sneak onto a pro bike (you'd actually be surprised as to how many cyclists smoke, particularly sprinters. Always amazed me to watch the dash after the field sprint where the sprinters would race to the nearest hideway to lightup.)

As mentioned elsewhere, the failure rate on wireless derailleurs is dumbfounding like when the batteries die the things drop into the largest gear. The real blindspot in implementation thus far is why should the batteries ever fail? Why not recharge the batteries either through a frictionless generator in the hubs or the very least a solar panel. Bike designers are always looking for ways to keep their lightweight machines above the UCI mandated minimum weight so why not?

http://www.ladyada.net/make/wavebubble/index.html

You know what I'd like to see? That new el-cheapo $25/$35 PC board working with some Heathkit designs for measuring house AC power consumption, maybe some water detectors, things like that. Perhaps an alarm system interface. Fun!

As much as I loved Heathkit, you don't need Heathkit, as people have already done projects like these (perhaps not as cheaply, though):

* Whole-house power monitoring: http://openenergymonitor.org/emon/node/43

* Single-outlet monitoring: http://www.ladyada.net/make/tweetawatt/

Hacking together a remote water detector should be pretty easy, too, with an xbee (it has built-in ADC and digital inputs).

"During the talk Eben explains that the $25 price point was decided upon because it is the cost of a textbook so it made sense. Students buy textbooks, so a PC priced the same is a natural fit and hopefully an easy purchase for them, their parents, or their school." [emphasis added]

Students also buy milk but it doesn't mean that therefore computers should cost the same as milk. I don't think that a real computer should be worth the same as one textbook because of the fact that many more than one textbook could be downloaded on it and thus much more money could be saved by children if that is really a fully functional general purpose computer that the story makes us believe it is. It is worth noting that unlike the $100 laptops, this computer is not complete. It doesn't have a keyboard, it doesn't have a display. It has a HDMI port - yes, that will help poor children who can't afford a computer more expensive than $25. Also, are they going to carry a plasma TV around to use it? Quite frankly I think that it would be a much better idea to offer a Fuzebox kit from Adafruit - a do-it-yourself retro video console kit with open source software and open source hardware - or even an Arduino kit with TV output. In this case however all we have seen so far is a promise to deliver a $25 embedded board which is nice but it can hardly be called a computer, and especially not a computer that poor children in developing countries would need the most. We don't even know how much RAM will it have, whether it will run Linux or even if it will be useful for anything more serious than hacking a simple embedded Linux project. Don't get me wrong, I think that embedded projects are a great way for children to learn how computers work. But this is not a substitute for a laptop, notebook or netbook that those children need. Even a tablet would be a better idea but we all know this is not going to happen because apparently taking a keyboard out of a netbook makes it somehow ten times more expensive. We need a cheap laptop, a fully functional, self contained computer that children can use instead of textbooks, not as just one of them.

Yeah but in practice, chargers don't limit their current to 500 mA. See: http://www.ladyada.net/make/mintyboost/icharge.html

While they compete and try to destroy each other, open source consoles like Fuzebox will get a major market share.

BWAHAHAHA. 99% of gamers neither know Linux exists or if they do, don't care. They aren't interested in being able to code their own games on an 8bit console nobody uses or play old 1990s games on an emulator.

Having heard this from the staff, PS3 and Xbox 360 are mostly trying to compete with each other. This includes both customers and exclusive game developers, like Rockstar and GTA series have been in the past with Playstation. That's also why I think both companies are shooting themself in the leg. While they compete and try to destroy each other, open source consoles like Fuzebox will get a major market share. You can code your games on them and play your favorite old games in an emulator, or modify to the devices to do whatever you want. All that while Sony actively works to close Linux and homebrew software from PS3. It's only a matter of time until Fuzebox and similar consoles will win.

That's not quite true. The iPhone is capable of drawing more power than the USB spec allows to charge (USB allows 500mA at 5V, the iPhone can draw up to 1A, IIRC). However, so as not to fry a USB port that is not rated to drive the phone, it looks for the voltage divider resistors. The charger you made should have had 15k pull-down resistors on D+ and D- in it to be a compliant USB host interface. I suspect few, if any, devices check for it, but the charger you made does not meet the USB spec. Any charger that meets the spec will work fine with iPhone, it just will charge at 500mA max, but it *will* charge. Check out the "Minty Boost" schematic here.

I don't think Apple actually documents what you have to do to get it to charge at full power, which is kinda cheesy, but it's well documented by people who've reverse engineered it.

Also, none of this is related to the actual article. The firmware in the battery is well beyond the point where the stuff you're talking about is checked. It's there to keep the battery from catching fire. All Lithium-Ion batteries have it. I strongly suspect that this bug is not unique to Apple.

Its just an onboard battery. You can probably even replace it with replaceable batteries if you want to put the work in. Or use an external power pack that runs off of store bought batteries to recharge it.

http://www.ladyada.net/make/mintyboost/

You may be interested in the Microtouch. http://www.ladyada.net/products/microtouch/index.html Have a look at the code for the demo programs. https://github.com/rossumur/microtouch

http://www.ladyada.net/make/tweetawatt/

You could also build your own. The Wave Bubble is a *bit* fancier than those devices, but since it closes the loop on jamming frequency, you're almost guaranteed it'll be dead on.

2) windmills do not HAVE to be "ugly." Seen kinetic art?

Maybe they can line the blades with LEDs and put on a POV off shore light show.

I think you are mixing her up with someone else? http://www.ladyada.net/bio/index.html

Actually, Ladyada is Limor Fried.

But both of them are absolutely hero material.

There is a 'trick' to it, but it's more of a hack around USB's limitations than an explicit lockdown ploy by Apple. There's not a cryptographic lockout chip in the Apple chargers or anything. They signal the charge current (as high as 1-2A, while the USB spec only allows 500mA) by tweaking the pull-up resistor values on the D+/D- lines which ordinarily allow the host to identify lo/full/hi speed devices.

If you have an older/unofficial/DIY charger which shows 'Unsupported', you can add 4 ordinary resistors to make it supported (and limit the charge rate, if needed):
http://www.ladyada.net/make/mintyboost/icharge.html

you think they can't afford the $10/month to get a licensed cellular number to transmit your location that has coverage all over the country? Tho if your paranoid a portable personal electornic counter measure such as... http://www.ladyada.net/make/wavebubble/

If you are interested in tracking the power usage of appliances via a computer, the open source tweet-a-watt is a nifty project you can build.

http://www.ladyada.net/make/tweetawatt/

2 years ago these specs would have been exciting

Yeah it's time to live in the now and solder together your own Fusebox.

'Duinos rock, especially if you have some computer background!!

The other place that might be of interest is this course from MIT's open courseware...it's also available through the iTunes U if that floats your boat! It is likely a little more theory than you are after at the moment, but it might be helpful/useful after getting your feet wet.

I personally have dove in and am only slightly ahead of you by picking up things online (case modding taught me a bit), and now that I consider myself a maker, there have been numerous times I have had a problem I wished to solve electronically and a few well placed google searches later I had enough of an answer to get something working.

Oh yeah, with the arduino's there are a tonne of resources available out there...I have gotten started with info from Lady Ada and this book

'Duinos rock, especially if you have some computer background!!

The other place that might be of interest is this course from MIT's open courseware...it's also available through the iTunes U if that floats your boat! It is likely a little more theory than you are after at the moment, but it might be helpful/useful after getting your feet wet.

I personally have dove in and am only slightly ahead of you by picking up things online (case modding taught me a bit), and now that I consider myself a maker, there have been numerous times I have had a problem I wished to solve electronically and a few well placed google searches later I had enough of an answer to get something working.

Oh yeah, with the arduino's there are a tonne of resources available out there...I have gotten started with info from Lady Ada and this book

Start here : http://www.ladyada.net/library/equipt/kits.html

Probably the lowest cost, best-value combination of tools and supplies.

Start with this book : http://www.makershed.com/ProductDetails.asp?ProductCode=9780596153748

Don't be afraid to blow stuff up. Hell, in all the best books/articles I've read about the very first thing the authors have you do is blow up an LED. Get used to it.

I have to second this. I just bought that book from the Maker Shed, and it is more comprehensible to someone with absolutely no helpful electronic background. I've been doing the experiments, and it's been great.

Start here : http://www.ladyada.net/library/equipt/kits.html

Probably the lowest cost, best-value combination of tools and supplies.

Start with this book : http://www.makershed.com/ProductDetails.asp?ProductCode=9780596153748

Don't be afraid to blow stuff up. Hell, in all the best books/articles I've read about the very first thing the authors have you do is blow up an LED. Get used to it.

Start with a kit, like these or these. See if you enjoy the practical end of putting something together. You'll need some basic tools - a soldering iron, sidecutters, solder.

If you enjoy that, then there's a bunch of different ways you can go, depending on what you're interested in. Microcontroller based systems, if you like software too, are easy enough to start working with. Or if you prefer analogue electronics, old school audio and radio, then you'll want to learn some more about the theory and practice and there are lots of good books there - I like The Art of Electronics but choose something that suits your style and covers the areas you want to start with.

But first see if you enjoy the mechanical end of putting a circuit board together.

Start with a kit, like these or these. See if you enjoy the practical end of putting something together. You'll need some basic tools - a soldering iron, sidecutters, solder.

If you enjoy that, then there's a bunch of different ways you can go, depending on what you're interested in. Microcontroller based systems, if you like software too, are easy enough to start working with. Or if you prefer analogue electronics, old school audio and radio, then you'll want to learn some more about the theory and practice and there are lots of good books there - I like The Art of Electronics but choose something that suits your style and covers the areas you want to start with.

But first see if you enjoy the mechanical end of putting a circuit board together.

http://www.ladyada.net/make/tweetawatt/

"My plan is to have each room connected to a 6-outlet power strip which powers all the devices in that room (each kill-a-watt can measure up to 15A, or about 1800W, which is plenty!). That way I can track room-by-room usage, for example "kitchen", "bedroom", "workbench", and "office"."

Get a kit with the guts of the project for $90 here (currently on back-order):
http://www.adafruit.com/index.php?main_page=product_info&cPath=32&products_id=143

Then you'll need a Kill-a-Watt meter (Get one from Amazon.com w/free shipping for $20).

You can have it upload data to pretty much any web service you want -- or just keep it in a local database, if that's how you roll.

I dunno, but she's cuuute.
EDIT:After reading this -- definitely girl, definitely hawt.
I think I'm in love...

If you want folks to use something that isn't "closed", then make it better than Eagle and have documentation that shows us how to make better stuff with it.

Right now, I can download eagle, find a bunch of "directed at n00bs" guides that take baby steps to end up at a fully functioning ready-to-send-off set of files. Just look around.

gEDA's website, on the other hand, has three links to tutorials, two of which are broken, and one that breezes through a lot of things. You want folks to use it? Cater to the baby steps and release good guides.

As a side note, there is plenty of images of the schematics for this project. You don't need eagle for that.

The logic of the hardware is free for anyone to use. There is nothing stopping you or me from taking her work and cranking monchrons out in our own form.

And this chick is nuts.

"Fresh Air"?!

...intended for city-dwellers who feel that their personal space is being overrun with undesired radio transmissions...for cleaning up the air around the user.

*sigh* poor old Slashdot... just another sign of the times we live in

Is this an effeminate male or a really ugly female?

No, I took your point perfectly well.

If you take a picture of a CRT with a fast shutter setting, you'll see that there's never more than a few scan lines lit up at any one time. See: http://www.youtube.com/watch?v=lRidfW_l4vs

The "persistence of vision" effect allows ANY light source, whether a laser beam or a flashlight, to generate an image when it is scanned out appropriately. For one neat example, check out: http://www.ladyada.net/make/spokepov/

Oh we have a spectrum analyzer here, thats what we used to debug the DIY cellphone jammer project http://www.ladyada.net/make/wavebubble