determining diodes/transistors for project

Just a few:

Speed Junction capacitance Gain Power dissipation capability Current handling capacity Junction breakdown voltages Physical size Price / availability

Some are more important than others - depending on the application.

well, I plan on starting as of january... but electronics comes natural to me... I just don't understand how to judge what needs to be used... I mean... I know there are different types of transistors... switching, amplification... etc... I just don't understand the difference in operation well enough to decide "what" to use.

because I've worked with electronics since I was 5... I have just recently started trying to create circuits... ;-D

You can probably get by with a surprisingly small number of different types that you can keep on hand for "general purpose" applications. For example, 2N3904 and 2N3906 transistors for small-signal applications, 1N914 signal diodes, 1N4001-1N4004 (last digit is for voltage range) small rectifiers. I expect others on this list will have their own personal favorites, but these will go a long way to getting you started. When you see a circuit design that does something "exotic" (like RF or high power), you can observe what devices are used for such purposes, and just go out and get those exact parts until you have enough experience to judge for yourself.

Best regards.

Bob Masta dqatechATdaqartaDOTcom D A Q A R T A Data AcQuisition And Real-Time Analysis

well... dad is an HVAC tech... so I know basics from him... but I'm trying to get a head start on the college portion... (HVAC is a bit different... you just "know" that the capacitor infront of you will get you good... and if you don't... you will as soon as you touch it...:-D )

How does electronics come "natural"?

Tom

The quick answer is ... Electronics 101 starts at you nearest teaching institution next year.

You have to understand a lot of electronics to pick the devices you need so before that you will have to rely on circuits designed by people with the required experience.

and now that you have turned 6 ;) you are ready for circuit design

Well, I did, with my Dad for starters, and later on my own, since I was a kid too, but when I studied for my EET there was nothing natural about it - it was hard work.

Tom