If you mostly do digital, I'd say just get the E6 resistors and capacitors, common connectors and switches, and but there's as needed for projects.
Unfortunately multi packs usually have the whole E12 series full of odd sizes, like as if I'm going to need a 68k resistor rather than 100k, in a situation other than a project I'm ordering stuff for anyway, but having the extra selection isn't the worst thing.
E12 is about being +/- 5% of your target resistance using only a singular resistor.
A couple of notes:
1. E12 kits plays well with +/-5% tolerance. You're covering the entire spectrum of resistances possible with your kit, within the error-specs of your resistor.
2. Trimmer potentiometers (cheap pots designed for only ~200 cycles of use or less) are the key component needed for most analog / accurate circuits.
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You can usually design a circuit with +/- 5% accuracy (nominal), and then have one or two key trimmer-pots tune to 0.1% accuracy at the end. Ex: You might have one trimmer-pot control an a voltage offset (ex: from an instrumentation amplifier), and a second pot control the scale / multiplier (ex: op-amp multiplier and/or resistor divider).
You may have 20 to 30 resistors all across your analog circuit, all within +/- 5% tolerances for various reasons. But these two control points at the very end can "trim" away your error and reach 0.1%, or better, accuracy, in practice.
But you have to be "close enough", and have "linear enough" behavior. E12 (aka: resistors all within 10% of each other) seems to be enough for most such projects.
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Digital circuits on the other hand, don't really care too much about this stuff. So you end up with a bunch of 100nF capacitors with 1k resistors just all over the project. That's fine too. You should build a stockpile of the components you plan to use.
E12 resistor kits + a set of trimmer pots are for analog circuits. At least if you want 0.1% or 0.01% tolerances (3 or 4 digits).
If you mostly do digital, I'd say just get the E6 resistors and capacitors, common connectors and switches, and but there's as needed for projects.
Unfortunately multi packs usually have the whole E12 series full of odd sizes, like as if I'm going to need a 68k resistor rather than 100k, in a situation other than a project I'm ordering stuff for anyway, but having the extra selection isn't the worst thing.