Finding Circuit Components? (resistors, capacitors)?

I’m pretty new to this but I’m trying to put together something from a schematic (see URL) . I made a list of the components and took the list to Radio Shack. On items like the resistors, I was able to find resistors with the same wattage but not the same tolerance. My questions are as follows:

1. Are the resistors and capacitors in this schematic unusual so that I’d have trouble finding them?
2. Are the percentages on the schematic actually referring to tolerance or are they just showing overall signal change?
3. If I am correct in thinking I need to trace down a 6.8K Ohm with 1% tolerance, where is the best place to find such hard-to-get parts?


2 responses on “Finding Circuit Components? (resistors, capacitors)?

  1. atstdriver

    The resistors you find at Radio Shack are carbon film, so they have a bigger tolerance range (i.e. less consistent); 1% tolerance resistors are metal-oxide film, and harder to find – Radio Shack does sell a 50-pack of 1% resistors here: – it may or may not have the values you need, but it might be worth a try. Otherwise, you might have to go online to find the parts, through a supplier like Digikey, Mauser, Newark, or a similar company. If you go that route, you might as well buy all the parts there – it’s much cheaper than at Radio Shack, but shipping will kill you if you buy tiny quantities.
    The alternative is to just try the circuit with the standard 5 or 10% resistors, or buy a bunch and test them individually with an ohmmeter to find ones that are right on.

  2. billrussell42

    Whoever did that design specified 1% resistors where 5% would be fine.

    Same with the caps and inductors. A pF cap at 1% is ridiculous, Usual is 20%.

    Looking further, a 555 with a 1 pF timing cap is also ridiculous, it won’t work.

    I think the circuit has no chance of working.


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