Accurately Measuring Precision Resistors

Confucius

Someone scratched graffiti the step near him.

Yes, but the original quote is rubbish, as we all know.

Confucius, he accused of many things he never say..........

It's just chalk, and not very ancient at that. ;-)

Best regards, Spehro Pefhany

Yes, I have my own doubts about attributing "man who have hole in pocket feel cocky all day" to the great philosopher Kong fu zi.

Best regards, Spehro Pefhany

degree.

precison

by the

That's not true. All electrical constants are based on physical constants, and can be derived from them.

Confucius

Well, if what Confucius said is true, then NIST must not be certain of the exact time. But NIST claims accuracy of something like 10^14 or so over their numerous standards..

Perhaps it should be "Man with one watch is deceived into thinking he knows the exact time.."

asked.

least

other

other

resistor,

sqrt(100).

the 1

distribution

increase

factor

Oh, okay. I had no idea of how expensive they are, only that they usually require some amount of manual labor, either in assembly or testing. The ones I have are wirewound, and the Micro-Ohm website says they are wound out ot wire that's as fine as .6 mil, which is 1/4 the thickness of a human hair. Must be a very delicate and tedious procedure.

Confucius

Of course. Haven't you seen those cartoons with the Ancient Greeks with the sundials on their wrists? ;-)

Confucius

Shame on you for not warning us that it would take 5 minutes to load that image, even with the fuzzed out face.

Speaking of fuzzed out faces, I saw (not by choice, btw) the sketches of Jacko's trial and they blurred out the faces of the witnesses. Pretty sad when they have to go _that_ far.

While theoretically true, this is practically useless information.

Not very practical. ;-) Also, one of them is *defined* by a world standard kept in Paris.

Best regards, Spehro Pefhany

Confucius

As an aside from that, from what I've seen on the likes of Antiques Roadshow, the ancient asian dress was just a simple pocketless pullover, and they used a bag hung from their belt.

The thin film type flow out of a resistor trimming machine in their thousands much like 5% resistors do.

Best regards, Spehro Pefhany

Hey, Watt, it's 700K from a mini-snappy digital. That's a fraction of a second on broadband. It's not like you're in Bangladesh or something. I'll remember not to post links to any real hi-rez photos from my digital SLR ;-)

I can see why the witnesses (or their parents/guardians if they were minors) might not want to have their faces plastered all over the papers.

Best regards, Spehro Pefhany

Ancient garments that I've seen depicted were similar to that. According to one web site, in Europe (and relatively recently compared to Chinese history) pockets developed from people hanging the bag (containing coins etc.) inside their garments to prevent theft. They then added a slit to access the bag without disrobing and pockets developed from that.

Best regards, Spehro Pefhany

nth

But

be

voltage,

Absolutely not. Last week I needed a 0.1 ohm resistor, so I took out the ref manual and looked at the wire tables, and found that 32 AWG has

The same can be done for a capacitor.

In this day and age, you can get remarkably accurate test equipment at a low to reasonable cost. I used to screw around with the same sort of issues, so I just went out and bought 2-3 pieces of decent test gear. You can get multimeters with basic accuracies of .02% or better for about $500, a little more if you want a big name. Once you get past about .1%, your test setup is probably less accurate than the instrument anyway.

Something I have really grown to like is a "component tester," a dedicated meter that measures (4 wire) ohms at DC and a few frequencies. It also measures L and C and D and Q, and expresses losses as either parallel or series R.

C.mon, Watt Sun. It's the 21st century. Treat yourself to some decent equipment. Think of all the money you'll save by not burning out your LEDs........

Great pic tho, worth the wait. Mor'n I can say for a lotta others. ;-)

of

Pretty

But these were sketches......

reward"

pullover,

The following para is from

"Netsuke served both functional and aesthetic purposes. The tradtional Japanese dress, the kimono had no pockets. The robes were hung together by a broad sash (obi), so items that were needed to be carried were held on a cord tucked under the sash. The hanging objects (sagemono) were secured with carved toggles (netsuke). A sliding bead (ojime) was strung on the cord between the netsuke and the sagemono to tighten or loosen the opening of the sagemono.The best known accessory was the inro, a small box used by the wealthy for carrying medicines and seals. Netsuke were also used to secure purses, and were widely used to hold the tobacco pouches that became almost universal with the introduction of smoking in Japan."