Resistors for precision equipment

MBFX

MBFX

Well-known member
Hi everybody! I am making a resistor decade box. It's really easy to get accurate resistors all the way down to about 100 ohms, but my 10 ohm resistors are all about 3% out, and my 1 ohm resistors are 40% out at BEST, with most measuring closer to 2 ohms. Where can I get a small quantity of through-hole, 1/4W, 1 ohm and 10 ohm resistors for this project?
 
Is it for pedal use for something else too? I don't think you will have much need for 1 ohm with pedal related stuff.

What about filing the resistors, or is that considered somehow unreliable? The idea is that you take something which is a bit under, and file away at it a little until it's where you want it. Then probably add some lacquer or similar so it won't corrode where you filed. I've done it once, but no idea how it fared over the years, or if it's somehow a bad idea to do.

Also, are you sure whatever you're measuring the resistors is accurate enough where it makes sense to be so strict with the values?
 
@Fama it's for pedal use, but I would like to have it be closer to lab-grade. I measure all of my components with a Fluke 73.

@Robert I saw those, but it looks like I have to order a bunch. If you have 10 1 ohm and 10 10 ohm you'd like to send me, I can send you money. If you have zelle, I could send you money before you even put anything in a box! I participated in the big box of pickups if you need any reference to my reliability
 
MBFX said:
@Fama it's for pedal use, but I would like to have it be closer to lab-grade. I measure all of my components with a Fluke 73.
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What pedals use 10Ω or 1Ω resistors? I've done dozens of builds and the only times that I have used anything under 150Ω was for low pass filters on the DC power supply.
 
PedalBuilder said:
What pedals use 10Ω or 1Ω resistors? I've done dozens of builds and the only times that I have used anything under 150Ω was for low pass filters on the DC power supply.
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A decade box is useful because I can dial in any resistance from 1 - 999,999 ohms! I'll probably only use a fairly narrow band frequently (for testing Germanium transistor-based circuits like Fuzz Faces), but it will save me a lot of time, clutter, and fiddling with my breadboard. Just plug in two leads, dial in my expected resistor value, measure my circuit, and then adjust as-needed. Very small resistances are mainly used to adjust larger values by small amounts, in this case.
 
I understand why you would want a decade box, but I don't get why you need it to go all the way down to 1Ω. I've built just about every germanium fuzz pedal, and none of them require anything close to ±1Ω precision for any of the resistors.
 
I need to dig this one out and get it finished up....
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PedalBuilder said:
I understand why you would want a decade box, but I don't get why you need it to go all the way down to 1Ω. I've built just about every germanium fuzz pedal, and none of them require anything close to ±1Ω precision for any of the resistors.
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I'm a scientist. I like precision equipment!
 
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