components
I am thinking about ordering up some parts for every day use. I am thinking about making one big purchase so as to minimize on shipping and other charges.
What are some of the components that any electronics hobbyist should have around ALL the time?
To put a little more scope: typically working with Arduino's, PICs and sensors. 5V – low current projects.
Looking for: component, value or range (if any), manufacturer (optional)
For example – Resistors, 1K through 100K 5W
Yes, they will degrade little by little; they will grow tin whiskers, maybe oxidize little by little because their casing will never be 100.00% sealed. Also the pin plating will oxidize, so you'll have to treat them before soldering. Also moisture can creep in, little by little... difficult to say if it would affect discretes like transistors a lot, but ICs will suffer.
Oxidization plays a role in IC degradation if the passivation layer has defects, but the killer is metal whiskers between pins, pads and bond wires. It doesn't cause gradual degradation; basically the chip works fine until finally a whisker causes a short circuit between pads and the chip dies.
Image: whiskers on a piece of zinc. Source: http://commons.wikimedia.org/wiki/File:Zinc_whiskers.jpg
I think your assumptions are correct. Going from left to right and based on something I found describing that kit as including one active and one passive buzzer:
That appears to be a potentiometer and the 103 marking will mean it's a 10K pot.
That looks likes it would be the 'active' buzzer that includes a driver circuit because it's larger and includes a positive designator on the label. Unless it's marked and/or you can get a datasheet from the supplier I can't think of a good way to determine the voltage, but considering it's described as being useful with Arduinos I'd try applying 5 V and measure the current it uses to make sure it's not more than an I/O line can supply (if that's how you'll be using it).
Yes that looks like an RGB LED. It might be a common cathode or anode and without a datasheet once again you'll probably have to do some testing but this answer about probing 7-segment displays could be applied to that as well.
The last one I'd suspect is the 'passive' buzzer that will just be a piezo element without a driver. They need an AC driver of some sort and it's probably safest to use a transistor for those such as detailed in the question Is this a proper way to connect a piezo speaker to MCU?
So you'll have some experimentation to do and without datasheets and part numbers getting the exact specifications of components can be difficult to impossible.
While it can cost a little more sometimes while learning it can be less frustrating to start with components of a known origin and most of the more professional suppliers like Digikey and Element 14 are quite easy to deal with even for low volumes. Especially once you get a feel for the components that will be most useful to have on hand and you're ordering a few things at the same time to offset postage.
Best Answer
Here is my general collection. Apart from the components listed below, when ever I by parts I usually by a few extras. It doesn't take long to build odds and ends that way.
1/2 W 1% Metal Film Resistors. All E12 values between about 100 R and 1 Meg. Random collection of values in 5W.
1, 10, 22, 33, 68, 100, 220, 330 nF 63 V film caps. A random assortment of electrolytics - 1, 10, 100 uF in voltages between 16 V to 63 V. A hand full of different value ceramics less than 1 nF.
General purpose PNP and NPN transistors. I typically have BC337/327s laying around, but just about anything will do.
2N7000 N-fet
Which ever high power BJTs and FET you come across. But it's hand to keep at least one decent N-FET laying around.
LM7805 and LM317s. These are almost indestructible. The 317's with a single resistor makes a really hand current source that's good when you want to protect an output or power supply but don't need anything to accurate. (The circuit is in the datasheet)
Opamps - TL072 or TL074 for a general purpose, low input current. LM358 are easy to get and while not rail-to-rail, can be used for many applications of a single rail. I also have a sampling of different rail-to-rail op-amps that get used occasionally.
Some shunt references. LM336, TL431 or many others. Adjustable ones are hand to keep on standby so you set them to the value you need.
1N4148's and 1N4007's.
A couple of spare micro-controller in you favorite flavor.
Crystals and load caps to suit your favorite micro-controller.