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It's an effect of the social and educational shift of our populace having zero interest in the technology behind all the gadgets they're using.

On mailing lists and other web-based electronics forums, the majority of people truly interested and BUILDING things with electronics are not hobbyists, they're engineers who also tinker with electronics in their spare time or as a second job.

Slashdot is probably not a good cultural place to ask this, but...

When was the last time you really repaired a piece of electronics? Was it worth it?

RadioShack stocked parts when it was common for any handyman to attempt to fix their home electronics. With costs down, and complexity up to the point where you need a hot-air soldering station to work on surface-mount technology/boards, and schematics published by manufacturers and given out with the equipment a complete relic of the distant past, no one repairs anything anymore unless they have formal training or have absolutely nothing to lose in trying.

Other things hurt the "old" RadioShack model also, like the proliferation of places like DigiKey and Mouser Electronics where you can order small parts in quantity cheaper than you could ever get them at RatShack, and have them delivered to your door next-day.

I'm amazed Fry's still sells oscilloscopes, really... and impressed.

Digi-Key

If Radioshack goes under, you'll still be able to get all sorts of weird parts at relatively short notice (albeit not immediately).

DigiKey is located in tiny Thief River Falls, Minnesota... about half an hour from Grand Forks, North Dakota and about 90 minutes from Fargo, North Dakota. They have a huge complex of warehouses full of electronic components. Every chip, diode, resistor, LED, sensor, etc etc etc you could ever imagine. Their print catalog is two inches thick and doesn't even contain half of their inventory! I've never toured their warehouse, but based on their inventory and quick shipping I can only imagine how awesome it must be!!

It takes dc and supplies dc. Doesn't that make it more of a converter?

And if so, it's no big deal. You can buy decent switched cap converters at Digi-key for a couple of bucks. I bought one not too long ago to step 14v down to 5 and supply 4 or so amps, and it was about the same size. The small footprint at 120w is fairly nifty, but otherwise I don't see the big deal.

This is a company that has hundreds of thousands of different parts in inventory. The online catalog pages show the current inventory, updated continually. This is Internet commerce done right. The site isn't decorative, but it has real data, like online data sheets, "related parts" lookup, pictures of parts for most of the inventory, and history data for everything you've ordered in the past.

We ordered from them perhaps fifty times during 2003-2005, and every shipment showed up on time, with no errors. No defective parts, either.

Digi-Key can be overwhelming if you're not into electronics. Here's the page for a DB-9 plug. This is one of over 3000 D-Subminiature connector parts. Click on "Technical/Catalog information", and you'll get the enginering drawings for that connector.

They even have phone tech support with a clue. I've called to ask about obscure errors in catalog specs, and was quickly connected to someone who had the data in front of them and was able to contact the part manufacturer to fix the problem.

You didn't mention the kinds of noise you're interested in keep out, or what kind of data your sensors return. I will therefore assume, "all" noise and many kinds of sensors.

The best approach to keeping something as electrically noisy as a PC from spoiling your results is to put it in another room and connect it only with radio or light. This also addresses the sound issue.

If the bandwidth on your sensors is low enough for RS-232 serial data, then you're in luck, dozens of manufacturers sell simple in-line isolators like this.

If the cable it's running through is still picking up too much noise then using fiber converters on both ends (like this) will let you bridge the gap with glass which is pleasantly resistant to electrical noise.

If you're currently capturing your data with a bunch of low sample rate A-D converters, and have a large wad of sensor lines going to the attachment-pod on the PCI card, now would be the time to get your university's micro controller enthusiasts to create a sensor polling device. On something like the Atmel 8515.

Such a sensor converter will run for days on batteries, and produces very predictable low amplitude noise that is easy to isolate. It comes with an 8 channel 10-bit A-D, and the best part is they are available in an easy to breadboard 40-pin dip for $4.58 through digikey (here search on ATMEGA32-16PJ-ND).

If the bandwidth of your sensors is too great for RS-232, the same tricks can be played with RS-485 transceivers which will do speeds into the megabits, and are available as cheap dip packages.

For speeds beyond the few megabits realm a "custom data gathering CF card" and a Wifi capable IPAQ running Familiar springs to mind as a good starting point. But here we're getting into the question of "What exactly is it you're doing on the Windows box?"

--Art

This is a myth perpetuated by PC hardware manufacturers somehow thinking they're special. Go look at any components distributor, and you'll find ample documentation for all sorts of hardware, especially for commodity stuff.

Except that even the cards with the 192kSample/sec DACs won't reproduce much above 20 kHz. Remember, in a proper design you have to follow the DAC with a reconstruction filter as your signal will have spectral aliases every Fs. The idea of running a 192 kSample/second rate is to allow the reconstruction filter to gradually roll off from 20kHz to the Nyquist frequency of 96kHz, rather than the rather sharp roll-off from 20kHz to 22.05 kHz you see in 44.1kSample/sec gear. You also avoid the sin(x)/x roll-off in the reconstructed audio, as the roll-off in a 96kHz Nyquist frequency system is still pretty flat at 20kHz.

However, if you wanted to experiment with this, you could try to find an old (and I do mean old) Zenith remote control from the 1970's - they used ultrasound rather than IR as modern gear does, at about a 30kHz frequency. You could then drive that speaker from a DAC on the printer port, possibly with a simple timer chip to create the sample clock so that the computer "thinks" it is seeing a normal printer on the interface (that way you can avoid a great deal of the latency issues, especially if you use a printer port with a hardware FIFO.) You could eliminate the reconstruction filter as the transducer will do most of your filtering for you. Failing that, here are some transducers that will Git 'R Done.

Let me state right up front that, technological and potential privacy issues aside, I don't think this is going to make passports any more secure. I further believe the arrogance shown by the U.S. towards other countries in this matter ("You WILL convert to this same standard if you want your citizens to be able to visit our country") is absolutely typical of our current administration.

In other words, I don't agree with it.

WITH THAT SAID: Allow me to point out a few facts, based on previously-published material and my own knowledge of RFID technology.

First and foremost: What no one seems to have noticed (it may not have been reported in TFA, which I've yet to read) is that the State Department is, reportedly, going to weave their idea of a Faraday Cage right into the covers of the new passports in the form of a metallic-filament weave. Bruce Schneier mentions this on his site already.

This should, in theory, effectively counteract any sort of attempt to read the thing remotely when the passport is closed. If you're really paranoid about it, you can place your passport into an ESD Shielding Bag, available from most electronic component distributors such as Allied Electronics, DigiKey, or Mouser.

On the subject of long-distance remote reading: I doubt very much we're going to see, as one other poster pointed out (paraphrasing), "criminals with laptops and a portable reader under their coat" any time soon. For starters, the return emission from most passive RFID chips of the low and mid-frequency ranges (125-148kHz and 13.56MHz) is very weak. The chip would require a significant amount of close-up RF energy to excite it, and a large antenna and high-quality receiver to pick up the return signal.

Going further along those lines: Remember that RF field strength decreases quickly, as you move away from the source, according to the Inverse Square Law. The main reason that the low and mid-freq chips are only readable up to about 3 feet away is because, in order to have them work from further away, you'd need a transceiver the size of a large HF ham radio setup, and equally large (and obvious) antennas (the lower the frequency, the physically larger the antenna has to be).

For a criminal to effectively read such chips with portable equipment, they'd have to be standing more than close enough to the security folk to attract unwanted attention.

While I have found some references to the State Dept. having been able to read the test passports from 30 feet away with "special equipment," I also recall that this equipment was hardly portable, and required direct connection to AC power to be operable at all. In other words, it needed a lot more power than an easily-portable battery source could provide, and it was hardly what I would call surreptitious. Based on that stated range, I have reason to believe that the DoS was using 915MHz RFID tags for their test. Such tags are, according to this list, very much readable from at least 25 feet away.

I've been unable to locate any references on which specific frequency or type of RFID chip will be used in US passports (anyone else have any references on that?) Despite that, I think it's premature to draw conclusions based solely on the news articles to date. News articles do not, after all, make for a technical white paper.

I would suggest that those who get the new passports, and that have the technical know-how, try to read them with an appropriate RFID reader. Try different distances and angles, see if you can actually read the thing with the cover closed and (if possible) try a variety of d

Have you ever bought an oscillator? Here is an example: http://www.digikey.com/scripts/DkSearch/dksus.dll? PName?Name=300-8079-1-ND&Site=US

Notice that it is a 33.3333MHz crystal. This implies an accuracy of around 0.00005 MHz and is fairly typical of crystal oscillators. You can also buy a 33.3330MHz (not 33.333Mhz, but actually 33.3330MHz) one from DigiKey. Seriously, they sell them that close together.

You are overestimating your knowledge. I had Horowitz and Hill's undisputed bible, "The Art of Electronics", open on my desk as usual, so I checked the index. "Power supply" refers exclusively to sources of DC power in TAoE. The AC mains are called simply "power lines" or referred to more specifically with voltage, e.g. "120V AC". I don't know why you think sticking the officious little word "unit" on the end of the common term "power supply" makes a difference. To me the word "unit" simply suggests that it is being treated as a black box component rather than as a mutable part of the circuit design. In context you could refer to the AC mains as "the power supply", but when used by an electronic engineer without qualification, the term means a circuit which provides a local source of DC, most often one which derives its own power from an AC input.

As for supercaps, the carbon aerogel Cooper-Bussman PowerStor 2.5V 50F (0.025ohms @ 1kHz, 18.5mm dia.x 42 mm height) caps are available for $17.26 ea / qty. 100. (http://dkc3.digikey.com/PDF/T052/0919.pdf, http://www.cooperet.com/products/products.cfm?page =supercapacitors). You would need 5-10 of these (depending on capacitance variance and circuit efficiency) to store 1 kJ (100W x 10sec) plus a fancy charge pump to get the voltage up to the 12V needed. A brute-force approach would use 24-36 caps and would leak a little due to the voltage-sharing resistors needed for series capacitors.) Not cheap enough, but getting there, as I said. Of course, if you only need enough power to refresh the DRAM and perhaps power a device other than the main processor which transfers the data to flash memory, then you would need much less juice. Also promising is the idea of using batteries bufered by supercapacitors for situations with a high peak/average current ratio.

If you aren't going to pay to have it fixed, then what do you have to lose. http://www.digikey.com/ Pick up a couple caps and go to town!

So... you're happy because you paid $12 for a four dollar part?

What I didn't put in the project web pages before it got /.'d: I'm making a case with integrated battery that mounts on the back of my R1150GS motorcycle. If I get the size trimmed a bit it should fit without taking up any of the bike's luggage space. Now to figure out how to make a lean-angle sensor to record that along with the speed/position data... :)

You could use the dual-axis accelerometer I used for the robot project to sense tilt changes. Have it integrate changes to guess at current tilt, and recalibrate itself by assuming that anything maintained for 30 seconds or more is a tilt of zero. You could combine it with one of the pseudo-gyro sensors made by the same company (Analog Devices), but be warned that they're ball-grid array packages (and it's probably overkill for your purposes).

Sounds like a good course... I wish I had something like that when i was in highschool :). Anyways, for parts, http://digikey.com/ is probably the best. You might also want to check out http://jameco.com/. If you're teaching robotics, you'll probably want some simple MCUs to teach basic microcontroller concepts with. I would suggest a simple PIC micro from http://microchip.com/ or better yet a BASIC stamp from http://www.parallax.com/

No need to demolish perfectly useful equipment for small parts (3.5mm stereo jack) any more my friend...

Just buy a few from Digi-Key and be set for life!

• Digi-Key (USA and Canada). Flat cheap shipping, sell most things in small quantities.
• Mouser.
• Jameco, although Jameco have crappy shipping to canada.
• Newark.

As well, there are a few off-axis surplus places (allelectronics.com, for example) that have super deals on things compared to the big suppliers, but less selection. Do you know a good surplus place? Add it to this thread!

The PC power supply will give you the wattage/current you need to operate most if not all your DC devices. You will need to wire the power supply so that it will stay on without being hooked up to a motherboard. For ATX p/s' here is an article on how to do it.

That will give you +/- 5 VDC and +/- 12 VDC. To get the 9 VDC used by many devices you need to add some circuitry. Basically you want to use a voltage regulator to reduce the +12 VDC to 9 VDC. This can be done with as few as 1 part but adding a few more for safety is recommended. Here is a quick primer on the LM78XX series voltage regulators (your looking for a 7809, like this) .

Regardless of what some posters say this does not have to be a big ugly noisy box. You will need some sort of case with ventilation for the ATX p/s and additional circuit. The fan in the ATX p/s should be enough to cool both the ATX p/s and the additional voltage regulators. If you use a bypass transistor to increase the current output of your voltage regulator or if you run the voltage regulator close to the max current you should attach them to a heat sink.

Also, from places like Digikey (or Jayco in AU) you can by barrel connectors (like the wallwarts have) to hook up so that you can plug/unplug your low voltage cables from your spiffy new box.

Overall this is a great first project to try so hop to it. Just make sure to post all the pictures and description of your project so we can /. your server. :-)

The above is not intended as a step by step howto instruction. It is intended as a starting point to research the correct way to construct your project. Tread carefully. You can also find lots of electronics sites that probably have the circuits you want and you can post to sci.electronics for help.

Merlin.

That's partially true. I believe the tag ID itself is burned, but some of them allow data to be written (as per this RFID datasheet.

Is actual data written onto the tags, or is it just an electronic ID that queries a database elsewhere?

Put a standard incandescent light bulb in the case, it should be able to produce enough heat. Maybe have it switched with a thermal switch like http://dkc3.digikey.com/PDF/T043/1075.pdf. Wouldn't be a bad idea to have the case fans switched with thermal switches as well (since you still want them half of the year). Don't forget to use a relay with the thermal switch & light bulb.

Oh, and to check on the parts that you linked, it looks like those are binary, "something's moving/not moving" sensors. Plus they're IR sensitive.

Digikey lists the pricing for the parts in the $30 range, for quantity 50, as special order items.

http://www.digikey.com/scripts/DkSearch/dksus.dll? Detail?Ref=211930&Row=208853&Site=US

hjames

When I was in middle school, I subscribed to the Digi-Key catalog by mail just because there was a lot of fascinating stuff to see...everything from connectors and cables to semiconductor devices to embedded computers to prototyping tools and software.

You can get their catalog in PDF format here.

When I was in middle school, I subscribed to the Digi-Key catalog by mail just because there was a lot of fascinating stuff to see...everything from connectors and cables to semiconductor devices to embedded computers to prototyping tools and software.

You can get their catalog in PDF format here.

I don't know much about FPGAs -- what will $30 get you?

$30 wouldn't buy you a lot, I think.

200k-300k gate equivalents on a Xilinx Spartan II or IIe from Digikey. "Gate equivalents", as I understand them, are the number of logic gates that you could get if you used every single resource on the FPGA (which is impossible of course). In practice, you'd get only a fraction of that depending on your design. Call it maybe a few hundred thousand transistor equivalents or so if you want to compare to ATI/NVidia's transistor count.

Your idea of using surplus is only good is you have whatever said surplus already laying around. I don't happen to have any of the old parts you mention (gameboys, zip drives, scanner, etc.) lying around, or you have a large enough surplus supply (electronic goldmine, ocean state electronics, ebay but prices get whacked quickly) on the market.

Experimenting with cheap 8-bit microcontrollers such as Microchip's PIC or Atmel's AVRs is quite cheap, and typically all you need is a chip and one (really cheap if want) device - a programmer to transfer the (binary/hex) programs from your PC to the microcontroller's flash memory.

You will quickly outgrow Radio Shack unless you need a part right now and you don't have the right one in your own stock pile, often referred to as a "junk box" regardless of actual physical size. You should be getting the free catalogs (or CDs) from Digikey, Mouser, Newark, and Jameco. These all have usable online ordering systems and reasonable minimum order & shipping fees. UK geeks check G3SEK's UK Component and Tool Suppliers web page.

Many useful projects can be made for less than $100 even if you need to buy all the parts. After you build a collection of common parts (common resistors, capacitor values, PIC 16F628, AVR AT90S2313, red & green LEDs, 2N2222A, 2N3904, 2N3906, 2N4401, 2N4403, 2N4416, 4N25, 1N4148, 1N4001, 1N4007, etc.) and tools this cost will go down.

The real question is do they assume a general audience or do they assume a "knowledgeable user" is their target market? If the stuff is purely "cookbook" & kit building (AmQRP kits as an example) with little or no encouragement (and knowledge transfer) for the average Make reader to explore and expand it won't survive IMHO. BTW AmQRP kits on their own are pretty limited at expanding your knowledge, but combined with the AMQRP Homebrewer magazine and Conference Proceedings they do teach a lot. There is also the QRP-L mailing list which is very useful for technical questions (and has a rich archive)

I think it should be what Nuts and Volts magazine tries to be, but without the "legacy" dead weight and filler articles. A gentler introduction to most of the Circuit Cellar type stuff.

If people think this will recreate the Homebrew Computer Club, I expect they will be mistaken, but if you expect it to awaken the curiousity and encourage youth to learn about electronics, then I hope it is a brillent success.

In the end, I am curious and not quite sure what to expect of Make. It could be really lame if all it ends up being is computer geeks pretending to be electronic engineers (or electronic hobbyists). I hope that at least 10% of it expands what I know, which is more than I can say of books like Hardware Hacking Projects for Geeks (O'Reilly) and Hardware Hacking: Have Fun While Voiding Your Warranty. I am more interested in reading stuff like Hacking the Xbox (An Introduction to Reverse Engineering) by Andrew "bunnie" Huang which starts simple but gets into FPGAs and reverse engineering.

I've thought about...putting a diode in series with each of my incandecent fixtures with a capacitor across the lamp to bridge the missing half of the cycle. While this won't actually save any energy, as you will be drawing twice the current through half the cycle
k4_pacific

>the diode prevents the cap from discharging energy back to the power company
> ericpi

True and true. Now...
Running a 100W bulb for half a cycle (8.3ms) requires 830 mJ.
If average energy is E = (CV^2)/2
then this takes a 115uF 250V lytic for each bulb
and a polarized plug for each lamp (1 amp diodes are trivial).
How long before payback on this scheme?

gewg_

I've thought about...putting a diode in series with each of my incandecent fixtures with a capacitor across the lamp to bridge the missing half of the cycle. While this won't actually save any energy, as you will be drawing twice the current through half the cycle
k4_pacific

>the diode prevents the cap from discharging energy back to the power company
> ericpi

True and true. Now...
Running a 100W bulb for half a cycle (8.3ms) requires 830 mJ.
If average energy is E = (CV^2)/2
then this takes a 115uF 250V lytic for each bulb
and a polarized plug for each lamp (1 amp diodes are trivial).
How long before payback on this scheme?

gewg_

In that case, you could do as many source colors as you wanted. Use four colors for IPv4. Use four cycles of four colors for IPv6. (There don't seem to be all that many different colors for LEDs. infrared, red, amber, green, blue, and variations on brightness and efficiency.)

Their film capaciter search: http://www.digikey.com/scripts/dksearch/dksus.dll? Criteria?Ref=248904&Site=US&Cat=30540500

Their list of other part searches you can do: http://www.digikey.com/scripts/dksearch/dksus.dll? KeywordSearch&site=us

Their film capaciter search: http://www.digikey.com/scripts/dksearch/dksus.dll? Criteria?Ref=248904&Site=US&Cat=30540500

Their list of other part searches you can do: http://www.digikey.com/scripts/dksearch/dksus.dll? KeywordSearch&site=us

> A year is long for RFID? I guess you're new to this topic.

Considering it hasn't made it to the market yet, yes, I stand by that assertion.

Hmm, not only have they "made it to market" (last year, even,) they're pretty widely used in warehouses and healh-care institutions. Moreover, you can buy some yourself at Digikey. Heck, even Froogle has readers and the ID's listed for sale. If you're looking to get started, Atmel Wireless has a nice demo kit. Once you get into it you may want to try one of TI's three nice evaluation kits before you start buying bulk RFID ICs.

> Whatever n00b.

I see. I'm dealing with a 14 year old. I should have known better on slashdot.

OK, maybe that was a bit out of line/ad hominem (I'm 34, BTW) but you are clearly new to (or underinformed about) this subject. I guess I should have just ignored your ignorance and informed you properly, but I think your tinfoil is interfering with your understanding (as is the case with many here on this subject.) I mean, I post "they have killcodes now, next issue" and I get a bunch of "nuh-uh!" posts from you and others, yet no one bothered to look. It's not that hard to research what's available.

> Listen, your paranoia is needed elsewhere.

I disagree. I find some healthy skepticism on topics like this to be far more useful than simply believing that the world will be a beautiful place if left in the hands of the corporate body. That would just be stupid and misinformed.

Healthy skepticism is what prompted RFID manufacturers to include the kill code. Which they all now do. Issue solved. But you're late and underinformed, and you want to keep wrapping on layers of tinfoil and ignore the way capitalism and market forces worked just fine in this case (not that they always do this well -- hence my comment above.)

Believe what you want, but the folks behind RFID are in it to make money. They don't have our best interests at heart, that's not their job. I respect them for that. I also expect people like you and I to question them at every turn to ensure that, in fact, trivial things like privacy will not be trampled.

They were questioned, and they responded. There's no market advantage to making a product that will draw protests or even a few complaints when it's cheap and easy to alleviate the problem (i.e., killcode) without hampering functionality.

If we don't ask these questions and force the issue, who will? Our political leaders?

Again, we did, and they listened. What's the problem with kill-code enabled RFID's again?

Really.

Learn more. Apply paranoia where required. When you misapply it, not only does it make you look like a nut, it makes everyone who complains about (even valid privacy issues) look a little nuttier. Really!

> A year is long for RFID? I guess you're new to this topic.

Considering it hasn't made it to the market yet, yes, I stand by that assertion.

Hmm, not only have they "made it to market" (last year, even,) they're pretty widely used in warehouses and healh-care institutions. Moreover, you can buy some yourself at Digikey. Heck, even Froogle has readers and the ID's listed for sale. If you're looking to get started, Atmel Wireless has a nice demo kit. Once you get into it you may want to try one of TI's three nice evaluation kits before you start buying bulk RFID ICs.

> Whatever n00b.

I see. I'm dealing with a 14 year old. I should have known better on slashdot.

OK, maybe that was a bit out of line/ad hominem (I'm 34, BTW) but you are clearly new to (or underinformed about) this subject. I guess I should have just ignored your ignorance and informed you properly, but I think your tinfoil is interfering with your understanding (as is the case with many here on this subject.) I mean, I post "they have killcodes now, next issue" and I get a bunch of "nuh-uh!" posts from you and others, yet no one bothered to look. It's not that hard to research what's available.

> Listen, your paranoia is needed elsewhere.

I disagree. I find some healthy skepticism on topics like this to be far more useful than simply believing that the world will be a beautiful place if left in the hands of the corporate body. That would just be stupid and misinformed.

Healthy skepticism is what prompted RFID manufacturers to include the kill code. Which they all now do. Issue solved. But you're late and underinformed, and you want to keep wrapping on layers of tinfoil and ignore the way capitalism and market forces worked just fine in this case (not that they always do this well -- hence my comment above.)

Believe what you want, but the folks behind RFID are in it to make money. They don't have our best interests at heart, that's not their job. I respect them for that. I also expect people like you and I to question them at every turn to ensure that, in fact, trivial things like privacy will not be trampled.

They were questioned, and they responded. There's no market advantage to making a product that will draw protests or even a few complaints when it's cheap and easy to alleviate the problem (i.e., killcode) without hampering functionality.

If we don't ask these questions and force the issue, who will? Our political leaders?

Again, we did, and they listened. What's the problem with kill-code enabled RFID's again?

Really.

Learn more. Apply paranoia where required. When you misapply it, not only does it make you look like a nut, it makes everyone who complains about (even valid privacy issues) look a little nuttier. Really!

> A year is long for RFID? I guess you're new to this topic.

Considering it hasn't made it to the market yet, yes, I stand by that assertion.

Hmm, not only have they "made it to market" (last year, even,) they're pretty widely used in warehouses and healh-care institutions. Moreover, you can buy some yourself at Digikey. Heck, even Froogle has readers and the ID's listed for sale. If you're looking to get started, Atmel Wireless has a nice demo kit. Once you get into it you may want to try one of TI's three nice evaluation kits before you start buying bulk RFID ICs.

> Whatever n00b.

I see. I'm dealing with a 14 year old. I should have known better on slashdot.

OK, maybe that was a bit out of line/ad hominem (I'm 34, BTW) but you are clearly new to (or underinformed about) this subject. I guess I should have just ignored your ignorance and informed you properly, but I think your tinfoil is interfering with your understanding (as is the case with many here on this subject.) I mean, I post "they have killcodes now, next issue" and I get a bunch of "nuh-uh!" posts from you and others, yet no one bothered to look. It's not that hard to research what's available.

> Listen, your paranoia is needed elsewhere.

I disagree. I find some healthy skepticism on topics like this to be far more useful than simply believing that the world will be a beautiful place if left in the hands of the corporate body. That would just be stupid and misinformed.

Healthy skepticism is what prompted RFID manufacturers to include the kill code. Which they all now do. Issue solved. But you're late and underinformed, and you want to keep wrapping on layers of tinfoil and ignore the way capitalism and market forces worked just fine in this case (not that they always do this well -- hence my comment above.)

Believe what you want, but the folks behind RFID are in it to make money. They don't have our best interests at heart, that's not their job. I respect them for that. I also expect people like you and I to question them at every turn to ensure that, in fact, trivial things like privacy will not be trampled.

They were questioned, and they responded. There's no market advantage to making a product that will draw protests or even a few complaints when it's cheap and easy to alleviate the problem (i.e., killcode) without hampering functionality.

If we don't ask these questions and force the issue, who will? Our political leaders?

Again, we did, and they listened. What's the problem with kill-code enabled RFID's again?

Really.

Learn more. Apply paranoia where required. When you misapply it, not only does it make you look like a nut, it makes everyone who complains about (even valid privacy issues) look a little nuttier. Really!

> A year is long for RFID? I guess you're new to this topic.

Considering it hasn't made it to the market yet, yes, I stand by that assertion.

Hmm, not only have they "made it to market" (last year, even,) they're pretty widely used in warehouses and healh-care institutions. Moreover, you can buy some yourself at Digikey. Heck, even Froogle has readers and the ID's listed for sale. If you're looking to get started, Atmel Wireless has a nice demo kit. Once you get into it you may want to try one of TI's three nice evaluation kits before you start buying bulk RFID ICs.

> Whatever n00b.

I see. I'm dealing with a 14 year old. I should have known better on slashdot.

OK, maybe that was a bit out of line/ad hominem (I'm 34, BTW) but you are clearly new to (or underinformed about) this subject. I guess I should have just ignored your ignorance and informed you properly, but I think your tinfoil is interfering with your understanding (as is the case with many here on this subject.) I mean, I post "they have killcodes now, next issue" and I get a bunch of "nuh-uh!" posts from you and others, yet no one bothered to look. It's not that hard to research what's available.

> Listen, your paranoia is needed elsewhere.

I disagree. I find some healthy skepticism on topics like this to be far more useful than simply believing that the world will be a beautiful place if left in the hands of the corporate body. That would just be stupid and misinformed.

Healthy skepticism is what prompted RFID manufacturers to include the kill code. Which they all now do. Issue solved. But you're late and underinformed, and you want to keep wrapping on layers of tinfoil and ignore the way capitalism and market forces worked just fine in this case (not that they always do this well -- hence my comment above.)

Believe what you want, but the folks behind RFID are in it to make money. They don't have our best interests at heart, that's not their job. I respect them for that. I also expect people like you and I to question them at every turn to ensure that, in fact, trivial things like privacy will not be trampled.

They were questioned, and they responded. There's no market advantage to making a product that will draw protests or even a few complaints when it's cheap and easy to alleviate the problem (i.e., killcode) without hampering functionality.

If we don't ask these questions and force the issue, who will? Our political leaders?

Again, we did, and they listened. What's the problem with kill-code enabled RFID's again?

Really.

Learn more. Apply paranoia where required. When you misapply it, not only does it make you look like a nut, it makes everyone who complains about (even valid privacy issues) look a little nuttier. Really!

From Atmel: 8051.

Some drivers/latches from Micrel.

And of course some LED blocks from Sun LED.

The 8051 handles incoming serial data as well as acting as a 'RAM DAC' to load the lines on the Micrels which act as line drivers to the LED displays.

The Micrel's can be bit-banged in a serial-ish protocol which corellates to outputs on the 8-16 pins on each micrel (ie: think of it as programming a multipin output chip via a serialish link).

The 8051 constantly changes which row of LED block its updating and goes about it's business. Ideally, the 8051 should be changing rows 70 times a second for a good clean refresh rate.

These really aren't any different from the LCD modules you can pick up from Jameco, Hosfelt, or MPJA (or perhaps Digikey).

And lets not forget Find Chips for all of your parts searching needs.

I have to report that the IDE is Windows based, not Linux like the poster asked, but I still reckon the kit is well worth the price.

Hardware is a 50MHz eZ80 processor, which can switch between old-skool Z80 (16 bit addressing) or new-skool ADL (24 bit addressing). 1MB Flash, 1MB RAM. Ethernet port, yay!. Various serial ports. A few buttons for inputs. 5x7 LEDs for outputs. Expansion bus connectors.

Software IDE is Windows based as I already said. You can choose between programming in C or assembler, and Forth is available from Douglas Beattie.

The kit even comes with a little box called a ZPAKII which connects the development kit to my home ethernet LAN. I can sit on the couch downstairs with my wireless connected laptop and program the device which sits on a shelf in the study upstairs. I thought embedded programming was meant to be hardcore and involve lots of pain, but this just feels ridiculously comfortable. [BTW when you open the ZPAKII you find it is just another eZ80 pre-programmed to interface between your LAN and the development board].

I'm well impressed, even if my girlfriend wasn't.

The development kit, which includes everything you need, can be had for under $40US. Sweet.

The AVR is wonderful. Note you can get a complete development platform, the AVR Butterfly, for $20 and the price of soldering down a 3 pin serial header. Digikey has a bunch in stock.

The AVR is a really powerful architecture, and the GCC toolchain works pretty nicely, though there are some idiosyncracies (the main being that register naming is not consistent between all the parts, and occasionally flags are wrong.

EPROM/EEPROM/FLASH, etc., burners are cheap (as little as $219) so I don't see why needing one would be such a big deal. I have an EPROM programmer at home I purchased several years ago for around $99 from DigiKey. Doesn't everyone own their own EPROM burner? ;-) My only concern would be whether or not the FLASH memory chip containing the BIOS is socketed. If it isn't socketed and it accidentally gets trashed, an EPROM/FLASH programmer wouldn't be much help unless you are very good with a desoldering tool.

Go buy a handful of These. Each one in parallel should draw ~1.0-1.3 Amps across a power jack, and scare the living crap out of whoever's showing you the office.

Or if you're feeling cheap, use These but don't leave them powered for more than 5 seconds. (read the datasheet).

Go buy a handful of These. Each one in parallel should draw ~1.0-1.3 Amps across a power jack, and scare the living crap out of whoever's showing you the office.

Or if you're feeling cheap, use These but don't leave them powered for more than 5 seconds. (read the datasheet).

Every board has a CPU (Actually, every chip is some kind of CPU), even if it is a dedicated CPU

• Here's a chip that's a resistor array... Is that a CPU?
• What about this TI uA741 Operational Amplifier?
• Are Optoisolators a kind of CPU?

Accelerometers are quite expensive ($100 for sufficiently sensitive ones.) They can be built into the notebooks; however with today's price of a new, good notebook being well below $1000 there is not much room for innovation...

You can still get them, but you have to go to a place like Digi-Key. They're just not all that common.

How obscure are we talking? Maybe you could do yourself a favour and check out digikey. Definitely one of my favourite suppliers.

These PowerStor 50F versions I have are around 1.5" tall and 0.75" in diameter. Very small for the capacity.

You can get them from places like Digi-Key and Mouser for pretty cheap. Fun stuff.

Aerogel caps ARE amazing tho. Only 2.5V but 50F in a very small package. Only a few inches high I think. (4cm by 2cm about)

A cm is this long ----- (not to scale) ;)

Datasheet with pictures here.

Did you try digikey.com?

They have a huge inventory, and will ship one unit of anything.

... and if you want that big honkin' LED display look, here are some 5 inch tall LED digits that will almost duplicate the classic Model H light bulb scoring display without the hassle.