Hi, I've been looking into getting an arduino and some basic parts to learn with before I go freelance with any projects. Ive seen a few kits on adafriut and sparkfun, but they seem a little basic and overpriced. Should I buy an arduino and then get separate components to assemble my own sort of "kit"? If so, what components should I get? Thanks
(By the way I live in the U.S., and have a budget of about 75 or so)
You live in the US? Then you should shop surplus, because we have a plethora of surplus electronics outlets to serve your need. Here's what you should do:
1. Look at the kits you're interested in, and come up with a list of everything in them.
2. Take that list, and price shop the items via surplus and "new" sources.
3. Order, and get it all cheap.
Make sure you get something to store the parts in. If you're just starting out (and/or have little space), I recommend you go to walmart or another such retailer, and purchase a fishing tackle box - one with a lot of individual compartments and such, plus a deep drawer area. The compartments you can fill with your parts (one type/value of part per compartment - though this can be tough with resistors, capacitors, etc - use your best judgement); the deep area will be for larger components (breadboards, small wire dikes, pliers, etc - you -will- need those tools). Later, you might need the room for soldering items (iron, solder, etc).
When you get your components - make sure you get the following as well for your kit:
1. A multimeter - the cheapest you can get is a Cen-Tech from Harbor Freight (or, if you don't have one near, look for a similar place - generally just about everywhere has some kind of cheap chinese tool warehouse available - you can get some of this at a dollar store, too); wait for the sale coupon, get it for about $2.99. These things are so cheap, I typically buy one every time I shop there. They may not be the best or super accurate, but they're fine for hobby work.
2. Breadboard(s) - if you can get a couple of the 800+ hole breadboards, you'll be comfortable for a while.
3. Small pliers and diagonal cutter (for stripping, cutting, and shaping hookup wire). Buy these are harbor freight too.
4. A magnifying glass or such (harbor freight again).
5. A set of small screwdrivers, plus some larger ones (harbor freight).
6. As many alligator clip jumpers of different colors as you can afford (at least a set of 10).
7. If you can afford it, get an old PC power supply and set it up to use as a bench supply for regulated DC - there are a ton of online tutorials on how to do this; it isn't as great a solution as a real adjustable bench supply, but it's much cheaper.
You're also going to want hookup wire for jumpers and such. If you can find it, go for about 6 feet of 24 conductor solid-core telephone cable. You will need some hefty loppers or something to cut this to size, btw - but it will be much, much cheaper than anything else. You may not even have to purchase it, if you know where and how to scrounge some up; if you have a building or something going under a renovation, sometimes they pull this stuff out by the mile and haul it away as trash. Ask around - look around (talk to people at the local phone company - maybe a lineman will give you some!). If you can't find it, then using solid-core cat5 is the next best thing (though it's a little thinner in gauge).
Ok - so where to get these parts? Three places I have had good dealings with:
All Electronics (http://www.allelectronics.com/
Electronic Goldmine (http://www.goldmine-elec.com/
Some parts, though, you may not find at the above places (like if you need a servo, or certain IC or other semiconductor components). For those, the next best way to go is via chinese suppliers on ebay. One good supplier I know of (great for LEDs) is a guy that goes by the handle "Asia Engineer". Another good seller (for motors, for the most part) is "80servo". You'll have to use your judgement for other things, though.
Finally, places like Mouser and Digikey are there for brand-new components that you just can't get any other way...
Actually, there is one way you can get some components - just be kind and don't overdo it, and only use it for those components that you have -no other way- to get. It's called "sampling". Some direct suppliers of components - ie, the guys who sell to Mouser, Digikey, and manufacturers - will allow you to sample certain component in small quantities if you ask them nicely, and don't bug them more than maybe once or twice a year. So, for instance, you can ask about sampling components from places like "National Semiconductor", "On Semiconductor" (formerly Motorola), "Microchip", even "Atmel", etc (also keep in mind for some small manufacturers who may sell only to other manufacturers - but sometimes if you ask nice, you can get 1s and 2s of some special components). Remember to ask nice, be courteous about it, and if they say "no" - leave it at that. Some may refer you to a local representative for your region; talk to them (you may have to talk on the phone). Sometimes, you might get a surprise, other times you'll wonder what they're smoking (I once tried to get replacement gears for a motor, the rep would only sell me a minimum of 50 pieces - at $7.00 each; which actually wasn't a bad price, for metal gears - but the motor was bought used for $10.00, so I passed - but I thanked him for the assistance regardless).
Now - there are more than those three surplus dealers here in the US; I have a whole huge list of links - I can generally find just about anything surplus instead of purchasing new. You might want to pick up a copy of Nuts and Volts Magazine and/or Servo Magazine; they'll have a ton of suppliers listed as well. I post a few more suppliers I know of (but haven't dealt with):http://www.herbach.com/http://www.surplussales.com/http://www.sciplus.com/http://www.mpja.com/
Oh - and for servos and other R/C gear (new):http://servocity.com/http://www.hobbyking.com/
Oh - one other thing to look into: A good lamp. If you can get one, a flexible neck magnifying lens lamp with a good fluorescent or LED lighting can work wonders.
I think that about covers it; welcome to an expensive hobby (no matter how you cut corners, it still isn't that cheap overall).