Please clarify European resistor value notation for me

I hope there weren't any fists flying ...

From what I understand there were "dominant" companies that wanted the standard their way _period_.

...Jim Thompson

-- | James E.Thompson, P.E. | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona Voice:(480)460-2350 | | | E-mail Address at Website Fax:(480)460-2142 | Brass Rat | |

If 802.3 is one of the *ANSI* IEEE working Groups I would expect ANSI to step in. Things like this can cause a Standards organization to lose their ANSI accreditation. Also, sometimes the Working Group members get overzealous and do not accurately represent their parent companies, in which case the parent company Members should fix the problem.

Don

What's going on with EDA advertising? Cadence keeps doing the same full-page ad with the pear-shaped psychedelic lettering that's ugly and unintelligable, and Mentor keeps running the repulsive mouldy-bread thing. I turn the page so fast, not only do I not read whatever blather they have to say, I also skip the ad on the facing page. I'd sure hate to spend $8K for a full-page ad opposite Mentor's green loaf!

They could at least give us the comic-book superhero idiocy that the other marketing twits think engineers are impressed by. Or pictures of robots. Or babies. Or baby robots.

Grrrrr.

John

Sometimes I have the impression that advertising specialists are among the most disconnected from customers. Right behind web site designers.

Why can't the Mouser web site designers figure out that 39.9K comes after 5K? Arrgh.

Or babes? SCNR.

Do not!

The lowest we - in my company - go in uF is 0.1. Below that, it's nF. It's a lot easier to say "point two-two mikes" than "two hundred and twenty nanofarads." We do say stuff like "two-twenty puffs", but we have no accepted shortcut for "nanofarads"... "twenty-seven nans"? I'll try that and gauge the reaction.

But why is it "simpler" in Europe? The cap value is the same. Hell, Americans pretty much invented electronics (tubes, transistors, ICs, lasers, fiberoptics, stuff like that) so naturally we have traditions.

We're also a lot less standards-oriented, so anarchy reigns in things like schematic symbols and notation. Fun, in my opinion.

John

European schematics don't confuse me, because I almost never see them. Do you guys still make stuff?

You give us credit for inventing Imperial units? For ohms, farads, henries, seconds?

Thanks!

John

AFAIR Lilienfeld and Dr.Heil patented FETs earlier, late 20's to early

Same in plumbing. The missus wants a new hot water dispenser so I have to figure out how to interconnect all that 1/2", 3/8" and 1/4" stuff. One of those back pain jobs coming :-(

I'm an American and I prefer the European method. The advantage is that you that you can see the decimal point (the letter) more easily. This causes far fewer mistakes.

Late at night, by candle light, John Larkin penned this immortal opus:

Let's just be happy the early scientists didn't divide and multiply them like the imperial length and weight measurements. Foot-ohms, mile-ohms?

- YD.

My favorite sorta recent promotion was when PSpice used a bottle of hot sauce in the add. And then produced bottles of real sauce with pretty good stuff inside. Unfortunately, my bottle is now empty...

Charlie

Agilent/Eagleware naming their time-domain simulator "Cayenne" was cute...

Darn, I missed that one. The best was a manufacturer of tank tracks. They gave out booze with their name on the label. The good stuff, 80-proof.

Maybe named after the Porsche Cayenne?

The number of missing-decimal-point mistakes I've seen made in the last 30 years can be counted on 0 fingers.

John

Ignore them.

Ignore ROHS.

Ignore ISO9000.

Ignore CE.

Ignore 2k7.

Enjoy!

John

On Mon, 11 Dec 2006 17:38:36 -0800, John Larkin wrote in Msg.

Actually the "2k7" notation is just a convention, just as drawing a resistor as a little box instead of a squiggly line. Unless you're required to stick to some convention by company rules (which no one seems to be around here) you can pick whatever you like better and go with that.

It'd be interesting to track down who started the infix multiplier notation, and where, and what their motives were, and if those motives indeed were to do it better than "the Americans" (actually it wouldn't be. The mere thought of doing the necessary research makes me want to go to sleep). FWIW it might as well have been started by some American company, probably to save a wee bit of space on a schematic, but only caught on in Europe.

So what's the problem? Someone comes up and says that they prefer to do something in some way that happens to be the way it is often done in Europe. Why sould you care? Just do whatever pleases YOU.

Recently I tried to remember if AoE (to which I refer almost daily) uses zigzags or boxes for resistors. I know it is an American book so most definetely it has zigzags, but I just couldn't visualize it. Could as well have been boxes. I had to check. It's the same for the infix/postfix notation. Apparently I'm equally comfortable with both systems, as I'm sure are you. After all we often use old schematics that used completely different conventions, or none at all. Ohmygosh! Can't use my old Burr-Brown book any more! They draw op amps with a bulging input side! And with thick lines! Whaa! Whaa!

BTW, I think it's sad that both Americans and Europeans pass up the opportunity to use _both_ zigzags and boxes in schematics. Both are visually appealing as well as distinctive and easy to draw. Maybe we can use the zigzags for wirewound resistors and boxes for thick-film.

By all means.

robert

Those of us who are consultants are often required to stick with a client's convention :-)

No sweat since I've got both versions in my CAD.

AoE uses the squiggly resistors. They are also faster to sketch on a white board because the marker pen doesn't have to be reset or looped.