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How about sources for new/surplus components?

http://www.goldmine-elec.com/
http://www.alltro nics.com/
http://www.allcorp.com/
http://www.new ark.com/
http://www.jameco.com/

Try to never buy from Radioscrap. Overpriced and crap quality...

I've ordered from Alltronics before. They have a $15 minimum order, and sometimes an order may be delayed if something you requested is out of stock. They answer your e-mails rather quickly, though.

Jameco also sells the seemingly elusive PCI prototyping cards, though they're pricey ($70). Anyone know another supplier of these? (They're also good if you're looking to pick up a 266MHz PII motherboard for $20)

=Smidge=

The Stiquito book and this site offer plans for converting a parallel port output to useful digital signals for driving actuators including relays and muscle wire.
Or you can just find some similar plans using a ULN2803 chip (including how to use it to switch LED's) online(PDF) I like your idea. If I get time, I may build one and mail you the plans.

Jameco has them listed for $159

Forget All Electronics, buy Jameco!

My understanding from surfing RadioShack Sucks is that their salesdroids would actually be penalized financially, or even fired altogether, for failing to obtain some arbitrary percentage of customer names and addresses. Seems like the quota was something on the order of 80-90% "compliance."

Between local stores like Active Electronics, the utterly-amazing variety of electronic parts on eBay and topnotch mail-order houses like Digi-Key, Jameco, and Mouser, it's pretty darned rare for me to set foot in a RatShit store these days. Their 1/4-watt resistor assortments are still a killer deal, though.

A cheap microcontroller and serial communication will get you started. Then it's just a matter of picking up all your LEDs, buttons, etc. from a nice cheap place, like Jameco will get you going. . . gl! --subhuman

If I remember right, Jameco's online site only has a subset of their inventory. For maximum browsing enjoyment, get their dead-tree catalog.

Great company, highly recommended. I've ordered from them on and off since I was in high school, way back in the 70's. (That's back when people still played with electronics as a hobby, and Edmund Scientific had some of the coolest, most exotic stuff I'd ever seen.)

*DigiKey and Mouser are more focused on commercial users, but they're great sources for hard-to-find parts, or a specific variant of a part.

1. Suppliers

Digikey absolutely rules. Largest variety of everything electronic. Very easily-navigated site. No minimum order ($5 handling charge if your order is under $25).

Jameco is a good second choice. Especially good for lots of different cheap power supplies.

With Radio Shack, this should be all you need for now.

2. Learning Resources

Someone already pointed you to the various cookbooks. TTL cookbooks are especially good places to start at your level.

A great online resource used to be ePanorama.net, but they're 404ing at the moment, so maybe they're gone for good and they'll be back.

Circuits Archive has lots of simple circuits you can peruse to see how stuff gets done at the lowest level, just like the cookbooks.

3. Advice

Stay away from FPGAs initially. I think you'll find the architecture and associated design process too big a piece to bite off at this point, and not worth the effort.

Focus on TTL and learning what functions are available in various packages (track down an old "TTL Databook" from TI; they don't print them anymore but they're much handier for learning and browsing than online equivalents, which assume youknow what you're looking for). See this for high-level descriptions and this for pdfs of actual datasheets.

When you're ready (which might be immediately) choose a microcontroller family to bone up on and stick with it. It's a huge waste of effort relearning architectures, instruction sets, and development tools for different families. For your purposes, either the PIC (from Microchip), 8051 (Intel et al.), or AVR (Atmel) will do fine (and they're all available from Digikey). I chose the AVR for the following reasons:

a) Wide (enough) range of parts, from 8-pin to 64-pin, 1K ROM to 128K ROM, various arrangments of on-chip peripherals (including A/D).

b) Cheap, from under $2/chip (single-piece) to under $30 for their fanciest.

c) ALL members of the AVR family contain on-chip FLASH ROM for program storage and can be programmed in-system directly via your PC serial port. This makes a HUGE difference (compared to external ROMs or on-chip EPROM) during prototyping.

Some people will suggest the BASIC Stamp from Parallax, which is a fine product which I've played with. My beef with it is it's expensive ($30 or so, I think) and all you really get for the money is a Basic intepreter. I think you'll find assembler for these chips so simple you don't need Basic. You can also get separate free Basic compilers for all of them.

Good luck.

Try this site (click on the catalog page for a pdf spec sheet). They have a card that turns your pc into a scope for like $300 bucks (vs thousands for a regular scope).

You can get that LCD from jameco, 128x64 Graphics LCD

The current ratings on the web site are wrong, check out the data sheet first. Very low power.

As far as designing your own chip, the only suggestion I'd have is to pay very careful attention to power consumption which is (relatively) very high for nearly every configurable chip you can get. You may end up looking towards CPLDs.

-Adam

Jameco has everything I could want, but their prices are absolutely ridiculous.

EPO and Fry's has the stuff too...need to go by and check prices.

Well, the video card does have TV out, so I'm guessing that it produces NTSC and VGA concurrently rather than sequentially?

I have experimented with outputting text. It is surprisingly clear, as long as I stick to (say) 30x10. But that wasn't my concern - the big hurdle was getting svgalib to work on an inactive vidcard. I figured I could put up some snazzy graphs that would offset the fuzzy text.

But I probably am going to have to go the character LCD route. I have an old 4x20 HD44780 based LCD that I can hook up to an EDE702 and then to a serial port. Same as a Matrix Orbital but half the cost. Color and graphics would have been nice tho..

My only big problem with that is that the EL backlight burned out. Any ideas on how to replace those suckers?

~wally

I've wanted something like this myself--but not for nearly as many devices. The basic problem is that there isn't really any standards across all manufacturers or devices. Think about your power requirements in more detail:

(1) Laptop: 19VDC @ 75 Watts (typically)

(2) Phone: 5VDC @ ~2.5 Watts (yours may be different)

(3) Walkman: Hopefully 5VDC, maybe 9 (Seen both)

(4) Camera: 5VDC, 9VDC, or 12VDC. Depends on camera.

(5) Razor: Mine takes 9VDC. I switched to Mach3s, recommend you do the same.

(6) Speakers: Who knows. Probably 5 or 12VDC.

See this, You use it to plug in electronic componates without having to solder or wirewrap them. The holes are electricaly connected in 5-hole patterns under the plastic face.

Radio kits just aren't as compelling as they were 30 years ago when I was that age. Today I think robotic kits are particularly compelling, and some even provide a jumping-off point for learning to program.

On a related note, I was also bitten by the LEGO bug as a youngster, and probably spent an order of magnitude more time building with LEGO than I spent building electronics kits. Something to consider...

For those who don't live in the Washington D.C. area, we recently had the Digital Edge Expo at the Convention Center. Among other cool things (such as a virtual-reality rollercoaster and Nascar racing), they had the ActiveMedia robot running around on the floor next to the ComCast booths! I spent more time playing with it than asking questions about how to ran; had I known it was running Linux I would have definitely been more interested in what's under the hood.

If you're interested in building a similair robot but don't have the money for an embedded-x86 architechture, take a look at the Basic Stamp from Jameco. It's a great way to get started with your own embedded projects.

I realize most of this thread has addressed the greater issues of how to raise children and provide a balanced education and such, and that's really a more interesting topic.

But to address just the question asked, here's my suggestion: get a JameCo catalog or visit jameco.com, and see what educational kits and/or books they have involving the BASIC Stamp. (Or see the manufacturer's site, parallaxinc.com.) This is a puny little computer that's programmed in BASIC. If the kid likes electronics, it's a nice way of combining that with programming. You can start out with simple things (flashing LEDs), and build up to more complicated things, like insect robots...what 9 year old geek wouldn't enjoy that! There are many areas of programming to learn, and embedded microcontrollers like the Stamp avoid a lot like structured programming and operating systems, but they teach the basics, emphasize efficiency, and can just be a lot of fun. :-)

For parts, I would try Digi-Key or JAMECO.

Anyway, they're fortunately easy to get. As the poster suggested, eBay is one good place; some retail stores sell them too; the only one I know off the top of my head is JameCo. Despite what this poster insinuates, also, they're cheap. JameCo has 'em for $14.95 a pop. I got my replacement on eBay for $3.

--neil, whose typing is mistaken for gunfire

I worked at GE for a summer deploying computers. We transferred HD images from the network down to the desktop's and laptops sometimes 8 at a time. We used KVMS switches from Rose Electronics. They work at all video modes, with all mice, and with all keyboards. I have never had a problem with using them. Rose Electronics can be found at this website.

At home I use a generic box from Master View. I ordered it from Jameco. They have several.

2 Port Switch $179.95
4 Port Switch $229.95

The boxes are daisy chainable, and I run at 1280x1024x85hz with no problems. In fact I switch between that mode, and 1024x768x70hz with no problems. But if you can afford it, I would definitely recommend the Rose switches.

I hope this helps you out.

Pete Brubaker
Purdue University - Computer Graphics Department

I worked at GE for a summer deploying computers. We transferred HD images from the network down to the desktop's and laptops sometimes 8 at a time. We used KVMS switches from Rose Electronics. They work at all video modes, with all mice, and with all keyboards. I have never had a problem with using them. Rose Electronics can be found at this website.

At home I use a generic box from Master View. I ordered it from Jameco. They have several.

2 Port Switch $179.95
4 Port Switch $229.95

The boxes are daisy chainable, and I run at 1280x1024x85hz with no problems. In fact I switch between that mode, and 1024x768x70hz with no problems. But if you can afford it, I would definitely recommend the Rose switches.

I hope this helps you out.

Pete Brubaker
Purdue University - Computer Graphics Department

I worked at GE for a summer deploying computers. We transferred HD images from the network down to the desktop's and laptops sometimes 8 at a time. We used KVMS switches from Rose Electronics. They work at all video modes, with all mice, and with all keyboards. I have never had a problem with using them. Rose Electronics can be found at this website.

At home I use a generic box from Master View. I ordered it from Jameco. They have several.

2 Port Switch $179.95
4 Port Switch $229.95

The boxes are daisy chainable, and I run at 1280x1024x85hz with no problems. In fact I switch between that mode, and 1024x768x70hz with no problems. But if you can afford it, I would definitely recommend the Rose switches.

I hope this helps you out.

Pete Brubaker
Purdue University - Computer Graphics Department