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Since when is a friggin' multimeter a "safety device?"

Multimeters are safety devices in the sense that they are often used to measure potentially lethal unknown circuits. There are different safety ratings which specify how much of an overload the meter must accept without failure or even improper operation. This is why the current ranges use (or should use) specially rated fuses which seem outrageously expensive.

http://en.wikipedia.org/wiki/M...

It was a long time informal standard to associate the color yellow with specially rated or ruggedized multimeters which is no doubt why Fluke adopted it for most if not all of their meters even if they did not meet any enhanced safety specifications which is deceptive at best not that plenty of other manufactures did the same thing. That standard has been deprecated by misuse so red or orange has become the new informal standard (also commonly misused) and of course Fluke marks their ruggedized and intrinsically safe meters in an alternative color style as well. I wonder if they will get a trade dress designations which include orange and/or red at some point.

The Beckman HD series of ruggedized multimeters from the 1980s are the first ones I remember that really took advantage of industrial strength yellow.

Since when is a friggin' multimeter a "safety device?"

Multimeters are safety devices in the sense that they are often used to measure potentially lethal unknown circuits. There are different safety ratings which specify how much of an overload the meter must accept without failure or even improper operation. This is why the current ranges use (or should use) specially rated fuses which seem outrageously expensive.

http://en.wikipedia.org/wiki/M...

It was a long time informal standard to associate the color yellow with specially rated or ruggedized multimeters which is no doubt why Fluke adopted it for most if not all of their meters even if they did not meet any enhanced safety specifications which is deceptive at best not that plenty of other manufactures did the same thing. That standard has been deprecated by misuse so red or orange has become the new informal standard (also commonly misused) and of course Fluke marks their ruggedized and intrinsically safe meters in an alternative color style as well. I wonder if they will get a trade dress designations which include orange and/or red at some point.

The Beckman HD series of ruggedized multimeters from the 1980s are the first ones I remember that really took advantage of industrial strength yellow.

Calling support for a multimeter? What planet are you from? Short of it breaking and needing a replacement under warranty, you plug it in, spin the dial to the mode you want, and away you go.

Do people call Sears for tech support on a Craftsman wrench? I’ll grant a multimeter is *slightly* more complicated of a tool, but really only slightly to someone who’s the least bit experienced in that area of tech. I think I got my first MM when I was six years old. Took Dad about 10 minutes to show me how to measure voltage and resistance, and that was when you had to set the range yourself.

Ever buy a $200-$500 multimeter? And then have problems with it? Maybe you'd be more apt to call support.

As well there's certainly liability. Here's a case where Fluke recalled meters:
http://www.fluke.com/fluke/cae...

So if a hazard were found on the meters they donated, Fluke would have to pay to ship and repair the meters. Because they are a real organization that stands by their equipment, not some Chinese knockoff outfit that couldn't care less if the meter failed to detect voltage when present or exploded when connected to voltage.

If I look at Fluke's versus SparkFun's, I, as a human, cannot differentiate a difference in the colors. And they both clearly bear an extreme semblance, which is what the trademark is about.

I'm curious, would you be so opposed if Pepsi copied a Coke can, and ever so slightly changed the tint of the red, such that it was "orange" and replaced the text with "Pepsi Cola"?

This model looks something like Fluke's 17B.
http://www.fluke.com/fluke/ine...

I'm sure there are other Flukes with a similar body as well. In any case, this reminds me of when I was shopping for a multimeter on Ebay. I had to beware of Chinese knockoffs made to look like the real thing.

Weather is not really a factor for most serious grillers. Having spent a few years living in the Cascade Mountains in Washington state, I've grilled outdoors with several feet of snow on the ground. And rain? This is the Pacific Northwest, if you don't want to grill in the rain, you might as well hang it up.

As for "geeky" grilling tools, long before high-tech met the BBQ grill, I was using one of these to temp my meat. Other than that all you need is tongs...

The BEST way to test it is something like this:

http://www.fluke.com/fluke/usen/electrical-test-tools/electrical-testers/fluke-1ac-ii.htm?PID=56048&trck=1acii

That's the deluxe "Amplified electronic testers (informally called electrical tester pens, test pens, or voltage detectors)", and I've actually seen functional versions at the dollar store.

Anyways, plug in the lights, and trace the wires from the live wire on the plug through the set till it doesn't light or just go side to side of all the sockets. No removing bulbs required until you find the bad one.

In fact work at a lab, and I say this was a major missed opportunity...

What they should've said is:

" Listen, your whole system is flawed and full of holes like a tennis racket made of swiss cheese.

For a start immediately buy our university department the following:

- One of each on their catalog...

- And their...

- And their...

...that should cost you only 50-100 million (you might get a discount). Budget it as a long term investment into transaction systems."

At least such a scenario is a recurring dream of mine. Oh well, back to the grind ... calibrating old Tektronix oscilloscopes...

I used to be a certified electronics calibration technician, and I've never noticed a difference between the analog and the digital.

If $2k is your budget, and not having any idea what you're going to be using it for, I highly recommend a handheld Fluke. They were just as reliable as the old analog ones, but with more features.

This is the model I'm referring to:

Fluke 125
Official Fluke 125 page

aero2600

In theory, couldn't you use a current loop probe? You wouldn't even have to connect any wires. Just the right signal processing and you're done.

Disclaimer: I'm not an EE

Since you say statistial, do you have any references to back that up? I am interested in how significant the effect is.

My personal favorite is Fluke "If it works, it's a Fluke".

You want the Auditor Collection CD and a decent directional antenna, such as a Cantenna or, if you have some cash, something by Huber & Suhner. Auditor is, by a far stretch, the best wireless security tools collection out there--it's a great complement to something like Knoppix-STD.

A Fluke Can help regarding signal strength, but the built-in antennas generally aren't great for spotting directions. They can help you start delimiting a general area without having you look like an idiot walking around with a laptop, though.

Also you may want to consider a Bumblebee -- I've seen one of these in use at PacSecWest, and it did a pretty good job finding transmitters. It's also a lot smaller than either a Fluke or a laptop.

If you're on a budget, try something like a Digital Hotspotter, although I wouldn't recommend this particular company due to delivery problems.

First, the method used by LostCircuits is not very accurate to begin with. The Fluke 80i-410 probe they used has accuracy of +-5% and a measurement floor of 2.5A. A current probe with a lower measurement floor like this one would have been a better choice. There is at least another case (XbitLabs) where a similar measurement showed that Venice uses more power than Winchester at the same frequency. Unfortunately, XBitLabs test doesn't mention which current probe was used.

Even if we assume that the current measurements were accurate, it is almost impossible to come to conclusions about the Venice core being more efficient than the Winchester core based on observations from one sample each. Note that the observed current consumption between the Venice core and the Winchester core is within a few percent of each other in most of the tests run by LostCircuits. You may see more than that much difference between samples from different production runs of the same core. The only thing that the Lostcircuits test proves is that AMD's 90nm cores are more power efficient that their 130nm cores...

Digital Phonimeters? Hmmm, I can see it now...

If you make yours an Extech, you would have a built-in laser!

If you got a Triplett, you could get a free poster!

And there's probably already a phone on some Fluke multimeter. Hell, this one comes with an orgasm.

A frequency counter is a standard bit of test equipment for people who have to test radio transmitters, be they these little very low power things like garage door openers, or big TV transmitters. What a frequency counter does is that it tells you what frequency your transmitter is ACTUALLY transmitting at (not what is being claimed). There are firms that sell frequency counters and building a frequncy counter is well with in the range of someone with reasonable construction skills, such as here or here.

Now for investigating aroung what you suspect may be a transmitter, well, a portable frequency counter will tell you if your dealing with a working transmitter, and if it is transmitting, what frequency the transmitter is using. That information can then lead you other places, like who is legally allowed to transmit on the frequency you are detecting...

Do your switches and LAN router(s) have statistic counters (# of frames of various sizes, undersided/oversized frames, flooded frames, deferred frames, etc)?

If you don't have a LAN router for 500 users: why?

What's the most amount of hops (switches) your packets will travel from one end of the LAN to the other? Any more than 3 and you should be putting a LAN router in there (ideally)

Do you have hubs? If so, destroy them all right now. Hubs are pure, unadulterated evil.

My point of that is simple: not all LAN problems are computer problems. Looking at the IP traffic doesn't always cut it. Re: the subject: At my workplace we have a nice LAN meter from Fluke. They aren't cheap but if you have that many users your company should damn well pay for the right tools for you to do your job.

Any one know what size hard drive this thing will use? If it is a standard 3.5", they could drastically shrink it if they went with those Toshiba hard drives that are 0.85". Would also decrease power consumption too.

I see a market for these as portable testing tools. Like a FLUKE or something similar. Especially if they add a laptop battery to it.

Actually, if a "wireless engineer" showed up with an Airport with a hole drilled in the top, I'd kick him out and tell him to get some real tools. Check out some of Fluke's stuff for starters, like the OptiView. Professional engineers use professional tools.

Its a great idea, and one that in the past Iv considered my self (More for gewizz then pratical value all be it)

But, in an office enviroment, having to check wire by wire is hell. Iv done a network test like this using a Fluke Network tester. At the very least, you need a pair of radios to go with them for talking to the guy at the other end!

Having something that scans the network from a single point is a much more appealing idea. And of course, having something thats not ease to do means you can sell if for more!

thad

The look is not what I would call "retro" its more like "Fortune 500 exec" if you ask me. Not to say that retro doesn't look good. I think retro is good up to the point that we take what was good from the past and leave the rest where it belongs, in the past. Wood has always had an appeal to the classier and wealthy or at least has that image. I mean would you want to put vinyl banasters in your 2.5 million dollar mansion? Of course not, it would look "cheap". Of course the look can always be overdone. Take the case of the '70s station wagons with their retro (simulated) wood panels. It no wonder that never caught on it was fake to begin with.

This is switching topics a little. But what I would do with the Palm Pilot is put on of those rubber inserts over it to make it more shock resistant. Something like the design of the Fluke Multimeters Holster.


Nathaniel P. Wilkerson
NPS Internet Solutions, LLC

Here's a particularly nasty toy you can make with some commonly available goodies, for all you Dr. Evil-in-training types (I wonderink if Mikhail makink these device when leetle boy, da?)

What You'll Need

• A brain. (You'd be amazed at how many people don't get past this point)

• A capacitor. The best types are the big old barrel caps from circa 1960-1970 TV sets... you know, the ones that look and feel about the weight of a relay baton. Polarized or non doesn't matter. Axial (one lead on each side) or radial (both leads on one side) are both fine, but radials take just a bit more work.

• Tin/Aluminum Foil. Not a whole bunch, just raid your mom's kitchen cabinents, or order some chinese food and use the tin from thier plates. As long as it's conductive, can be easily wrapped a cylindrical object, and cheap, it'll do.

• Electrical Tape. You MIGHT be able to substitute duct tape, but apparently some substrates can become conductive under certain circumstances. Best to play safe and get the genuine article (the black rubbery stuff).

• Some wire, soldering iron and solder. Not much solder is needed, nor wire. In fact, if you have an axial (one lead on each end) capacitor with long enough leads, you may not need these at all.

• A continuity meter. The best in the world are made by Fluke Industries. No self-respecting electronic/electrical engineer would be caught dead without one. Of course, deletantes may use whatever cheesy little analogue meters they find in thier gran-pappy's toolkit.

• A power source. The best are ones are bench supplies which can generate a specific voltage, but even a cheap-ass wall-plugged model will do in a pinch. Try to get it as close to the rating of the capacitor as possible. I've found that a couple car batteries in series makes a good 24v or +/-12v supply in a pinch, so long as they're kept charged and outdoors when not in use. Oh, and try not to spill their contents on your Nikes.

1. Read the Fine Print. I absolve myself of all issues that may arise from you assembling and using this little beast. Don't blame me if you use this on the head jock of your school and end up getting a boot up your ass. You're a big boy and/or grrl and you know what you're getting yourself into. CAVEAT ENGINEO.

Discharge the Capacitor. Just bridge the leads of the capacitor with some wire, a screwdriver, or any other ol' peice of metal you got on hand. Better safe than sorry... at least for the time being. >B)

(optional) Extend your Leads. Depending on the size of your capacitor and the length of the leads, you may need to add a little more metal on to the end of 'em. If you have a radial style cap (two leads at the bottom), you'll probably need to extend one lead so that it'll reach up to the top of the cap.

Tape Up the Cap. Lay down a layer of tape across the length of the capacitor. Don't leave any metal exposed except for the leads themselves. If you have a radial cap, run the long lead along the length of your cap and tape down two-thirds of it overtop of the base layer to electrically isolate it until it gets past mid-way up your cap.

Make Your Contacts. Tinfoil time! Cut out 2 strips. Make them wide enough so that they're just a bit less wide than half the length of the capacitor, and long enough so you can wrap it around a few times.

Attach the Contacts to the Cap. Tape the short end of one of your strips to the barrel at one end. Wrap it around once, then put the lead for that end on the foil and continue wrapping (with that lead embedded in the foil) until you run out of strip. Tape down the short end and long ends of the exposed foil, then repeat for the other end. Make sure the foil contacts don't touch in the middle, and only make contact with one capacitor lead each. The intent here is to make two really big foil-based leads to the capacitor.

Test the Contacts. Pull out your continuity tester and put one probe on each of the two contacts. If you did it right, the resistance should start close to 0, then steadily increase to infinity. This is because testers use a little current to see if there's a connection, and you're slightly charging the cap when you test. If the resistance stays at or near zero, you either have a dead cap, or you have a short between the two contacts.

Charge 'er Up. Set your voltage to the rating on the cap (or as close as you can get) and let it sit for a minute. Right now you're sucking billions of fun-filled electrons from one plate and depositing them on another inside the cap. Can't you just feel the tension?

Choose Your Victim Carefully. Young, relatively healthy individuals of whom you know you can run faster are best. People you really dislike are also good. Try to avoid old people, people with pacemakers, epilepsy or similar physiological/neurological disorders, people holding hot drinks (cold drinks can add to the fun ;), sharp or heavy objects. People who own lots of guns are probably not very good targets, but YYOJ. Remember the fine print.

Special Delivery! Hold your device with a glove, or carefully by only ONE contact. Approach your victim, and when about 10 feet away or so, shout "Hey , catch!" and gently toss the thing to 'em. Human nature is such that it makes us believe that small, slow moving objects should be caught in those situations, typically with both hands.

*POP!*

Laugh Your Ass Off and/or Run Like Hell. Self explanatory. Hope you had fun. Besides, you have to run home and build some more, unless your victim forgets about the thing and leaves it on the ground for some other Geek to take home and play with. Ah, the joys of simple electronics. The idea can be scaled down to smaller caps too (for little bitty jolts) if you want. Axials work MUCH better in those situations, as trying to line up the wires on one inch wide caps is a major PITA. For small caps, discard the tinfoil and just wrap the leads around the barrel as long as you can without them touching. Some hot-glue might be useful to hold things down. Make sure they're at least large enough to be easily visible to the naked eye while in the air, as they have to be seen to be caught. Have fun, and play safe!

--
rickf@transpect.SPAM-B-GONE.net (remove the SPAM-B-GONE bit)