Are resistors directional?

[Stoday]

When I first started looking at these things, 55+ years ago

The colours were body, tip, spot rather than bands. As for tolerance

 

[JohnW2]

When I first started looking at these things, 55+ years ago The colours were body, tip, spot rather than bands. As for tolerance

Yep,got some of thsoe in the cellar, too

If there's an age competition going on here, I think you probably do win. Thinking more deeply about the "45+ years" I quoted before, I think it was probably about 51/52 years ago that I first 'started looking at these things'. In those days, most of my stock of passive components came from scrap TVs discarded by the repair shop who's premised backed onto my parents' garden!

Kind Regards, John.

 

[ban-all-sheds]

Is it just me, or are resistors getting smaller these days?

 

[Paul_C]

The colours were body, tip, spot rather than bands. As for tolerance

The tip at the other end - No potential for confusion as to which way round it was to be read, as 5% was the tightest tolerance available.

 

[JohnW2]

Is it just me, or are resistors getting smaller these days?

No, it's not just you. It's all very well people joking about Specsavers, but I literally have to get a magnifying glass out to try to read the bands on some of the resistors around these days - and many of these tiny critters appear to have the same power capability as ones one could actually see a few decades ago!

Kind Regards, John.

 

[matt1e]

Talking of resistors, What method did you use to remember the color code?
Mine was always

Bad Boys Rape Our Young Girls Behind Violets Garden Wall

Still had to remember black was 0 and brown 1 though

Matt

 

[Paul_C]

Talking of resistors, What method did you use to remember the color code?

Funnily enough, despite the numerous mnemonics for such things as the resistor color code, telephone wiring color codes, etc., I had them memorized before I ever heard most of the memory aids.

Mine was always

Bad Boys Rape Our Young Girls Behind Violets Garden Wall

Still had to remember black was 0 and brown 1 though

Change "Bad" to "Black" and that's that problem solved. There are a good many variations of that same basic theme though. The version I first heard also changed the last part to "But Violet Gives Willingly."

 

[ban-all-sheds]

Change "Bad" to "Black" and that's that problem solved.

And another one created....

 

[matt1e]

Change "Bad" to "Black" and that's that problem solved. There are a good many variations of that same basic theme though. The version I first heard also changed the last part to "But Violet Gives Willingly."

Ah yes Paul I've come across those variations too
There was another one that was totally different too but for the life of me I can't rememmber what it was

Matt

 

[JohnW2]

The colours were body, tip, spot rather than bands. As for tolerance

The tip at the other end - No potential for confusion as to which way round it was to be read, as 5% was the tightest tolerance available.

Indeed - here's one with a gold (5%) tip marking. As Paul points out, had 1% or 2% one's (brown or red) been available at the time, that would have resulted in potential ambiguity.

Untitled

• JohnW2
• 7 Sep 2011
• 2

Kind Regards, John.

 

[ban-all-sheds]

The problem with mnemonics like those is that they don't help you much when you've got 3 colours beginning with 'B', and 2 with 'G' (3 if you include the 10ֿ¹ multiplier.

Remembering the sequence of colours in the spectrum helps a lot.

Here's an all-encompassing one for you.

Bad beer rots our young guts but vodka goes well – get some now.

 

[Paul_C]

There was another one that was totally different too but for the life of me I can't rememmber what it was

Bye Bye Rosie, Off You Go, Bristol Via Great Western ?

You still have to sort out black, brown and blue though.

 

[ban-all-sheds]

The colors are sorted in the order of the visible light spectrum: red (2), orange (3), yellow (4), green (5), blue (6), violet (7). Black (0) has no energy, brown (1) has a little more, white (9) has everything and grey (8) is like white, but less intense.

 

[Paul_C]

I think the spectrum sequence is why I, probably along with many others, never really had any problem memorizing the code without any of the various aids. It's easy to visualize black as being zero, or nothing, then brown seems to sit quite naturally between black and red. White being the opposite end of the number scale from zero, with grey just below it also seems natural.

As John mentioned earlier, this is one of those things where after a while one doesn't consciously have to "work out" the values anyway. Just as we recognize a complete English word as that word without mentally stringing together the sound of the individual letters, so after a little time working with resistors one soon recognizes the complete combination of colors as being a particular value rather than having to mentally "build" the value as "this digit, then that digit, then so many zeros."

The tip at the other end - No potential for confusion as to which way round it was to be read, as 5% was the tightest tolerance available.

Indeed - here's one with a gold (5%) tip marking. As Paul points out, had 1% or 2% one's (brown or red) been available at the time, that would have resulted in potential ambiguity.

Just to make it clear for everyone, 1% and 2% resistors were available then, just not in the body-tip-spot coded style as shown in John's picture.

 

[JohnW2]

I think the spectrum sequence is why I, probably along with many others, never really had any problem memorizing the code without any of the various aids. ... As John mentioned earlier, this is one of those things where after a while one doesn't consciously have to "work out" the values anyway. Just as we recognize a complete English word as that word without mentally stringing together the sound of the individual letters, so after a little time working with resistors one soon recognizes the complete combination of colors as being a particular value rather than having to mentally "build" the value as "this digit, then that digit, then so many zeros."

In fact, even to this day, what my mind has subconsiously assimilated does not seem to be the individual digit-colour relationships (i.e. I would probably have to stop and think before telling you which colour corresponded to 6, 7, 8 or 9) but, rather, 'two-digit' combinations. In other words, I instantly recognise (and subconsciously translate into the corresponding digits) the colour bands corresponding to the first two digits of the E12 range, and also instantly take on board the 'decade' of the component by 'taking in' (subconsciously) the third band. Hence, with E12, and probably much of E24, it is generally a case of 'look and know' - although I do have to think for values less that 1Ω.

Kind Regards, John.