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Resistor Color Code Training

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i remember time when seeing resistors with only 3 bands was not out of this world (sign i'm getting old?)
tolerance was just 'invisible' or 'body color' representing 20% (mainstream was 10% and 5% was 'precision').

no doubt SMD is dominant these days in anything compact but the through hole components are not dead yet.
i see lots of through hole parts on larger power devices, of course on older equipment and nearly all prototypes.
also quite often spare part is taken from another unit, specially when working in field and later on, the other unit is repaired in shop.
and finding color coded resistor on a large board is a breeze when it's color coded.
working with smt in same condition is not very likely to happen in field, and if you drop something, you'l most likely never see it again.
one need to take it back to shop, sit down, make sure there is nothing else on desk, pull lamp closer and aim it at suspect, i mean board...
but i like smt exactly because of small size. advances in miniaturization made many things we enjoy today possible.
 
My training I did with real resistors.

Sorry but this app sounds like the one somebody proposed to keep an inventory. Not of use for me at least.
 
I lust had a quick look in my resistor drawers at some of the annoying 5 band 1% types and found;

brown black black red brown (in one drawer)
and
brown red black black brown (in another drawer)

Mongrel things. ;)
 
A few of my resistor date back to the 80's. They banding has faded or shifted enough that I do not trust them. When I started working with them I had forgotten the codes and started using a multimeter instead of reading them. I am still doing that and quite happy to continue.
 
At work we had a selection of Allen Bradley (sp?) precision resistors from the 80's. Several failed open circuit in prototype circuits under test with no duress. I binned the entire lot. About 100,000 of them. It's not cost effective when they are a few pounds to replace a whole E series and product testing is an expensive business to start with.
 
It would have been nice if they had kept the original flesh colouring even for the metalised resistors.

I found another .... black black black gold resistor.
 
I found another .... black black black gold resistor
maybe an early attempt at a jumper that can be pick and placed by a machine? since the mid 90's they've all got just one black band on them...

when i was at that prototyping place, there were a few simple layout rules, and i'm sure it's derived from some MIL spec or another.... all polarized components have positive "up" or to the left, all color coded components have the first band up or to the left, all diodes have their cathodes up or to the left, all digit marked components (resistors, caps, etc...)have their values showing. all transistors have their markings side "down" or to the left. IC's always have pin 1 oriented towards the top left corner of the board. the schematics are marked with pin numbers, with the "1" on two pin components being the "up" or left pin (this simplifies the making of wire lists. and those wire lists were done by hand.). we used a lot of wire wrap in those days, but all CAD programs tend to use the same conventions.
 
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