Instrumentation Advice Wanted

It depends on what you want to do. For 1% accuracy, you don't need to spend $100, your $10 meter is probably that good. I work on $6,000 meters with better that 1 part per million accuracy, but not everybody needs them. I would wait until you have a job, and get experience with the instrumentation that they have, then decide what to buy yourself.

I guess it would depend on what you want to get into now and in the future.

Is it worth it to get a 1 GHz frequency generator if you're going to be working on audio frequencies only? Then again, if you envision yourself working on very high or ultra high frequency equipment in the not-so-distant future, maybe 10 GHz might be a little too low.

How accurate do you need to be? Is +/-2% okay or do you need +/-0.01%? The thing with accuracy is that people always want the highest accuracy...period. I've had to contend with that off and on ever since I got into instrumentation. You'll have to determine for yourself what level of accuracy you need and select your instruments to match.

Features. Again, some are nice-to-have while some are must-haves. Personally, however, digital storage scopes are among the must-haves. I can't count how many times I wished I had one of those, both at home and at work.

Fluke meters are fantastic, in my opinion. They're very robust and work very well. Again, choose the features that you want. I particularly appreciate min/max readings and newer models have calibrating functions.

If you'll be working on motors, a good insulation tester and low-resistance meter are must-haves. Clamp-meters too.

These are all just off the top of my head. The others may be able to offer additional suggestions.

Bare Bones instruments and tools...

Most professors cannot advise you because they have learned from the books and don't really know which end of a screwdriver to hang on to. They can teach you the fundamental theory, but you have to develop the skills.

First. (This is a MUST) You need at least one bench mark meter for accuracy. You need to know if you have 5.0 volts or 5.2 volts and .5 ohms and 1.0 ohms. Also 1 meg or 1.5 meg ohms. many meters including the hand held fluke's meet these requirements. There are other brands, with out the name that can save you some money, and are good, If you are measureing complex waveforms, you will need an RMS meter, but don't buy cheap tools and meters. Fluke is not the only one that makes good meters. But check the accuracy and also the ease of measurement. You do not want to be switching leads back and forth in the holes.

Second. (depends on what you are working on) if you are working on audio, you need a generator for signal insertion, very simple devices are available for this purposes. If you are working on RF (as TV receivers) you need a RF generator that covers the signal frequencies and the intermediate frequencies.

Third. About scopes. Many people cannot read a scope. It takes hands on training and lots of practice, but once you learn how to use it, it can be the most valuable tool on your bench. A two trace 50 MHz (triggered sweep) scope is inexpensive and can be a very useful learning tool. You say that you are using a Junk TV as a scope, so you already understand the importance of it. It's good for logic and audio circuits, and you learn the fundamentals of using it. You will know what you are looking for when you later shop for a better one with delayed sweeps etc.

Hand tools. select them carefully... Your dikes need to be good quality steel, your needle nose pliers etc can be cheaper as long at they are comfortable to use and the jaws line up properly. Cheap screw drivers and Allen wrenches are worthless. They damage more screw heads than they are worth. A good bench lamp is a Must and a padded work area is desirable to protect scratching equipment on the bench. Grounded soldering irons and static wrist cuffs should be considered. Wire strippers come in cheap, expensive and clumsy. Some of the cheap ones are the best to use. You don't want to have to open the handles to inset the wire behind the hinge.

Look at Radio Shack for the $10.00 solder sucker with iron. There are times when your expensive thermostat iron doesn't work very well for removing components from circuit boards. Except for the sucker, always use the thermostat iron on circuit boards so as not to overheat them and have the lands come up.

This list is getting kind of long, maybe it requires another later supplement. I am sure that many others will add to and/or question my statements, but my comments stand on many years of experience.

Snakers

The basics you need are three types of equipment, multimeter, oscilloscope, and signal generator (buy lots of them because you could need to look at many points at the same time). You should develop the habit of practising to USE what GOD gave us... ie. TWO EYES!!!! You should use the multimeter AND oscilloscope together at the same time looking at the same point; as this will give you the confidence to believe what you see.

It is also useful to have a full range of resistors and most capacitors in your stock, as well as making up test clips using a combination of croc-clips and banana plugs, as well as any other of your favorite plugs and sockets.

Agree with Vulcan, Fluke multimeters offer a wide range of multimeters that are robust, cost effective, and are good "work-horses". I get that you are after general purpose stuff for now. Generally if you need to measure something at X%, then you should use an instrument that is 10 times better on accuracy, so to measure your 1% easily and quickly, then a 0.1% multimeter is what you need.

In this life you need to SAVE YOUR VALUABLE TIME, so start REMEMBERING what you learned in 1st year... don't throw that away, most people do!!! e.g. if you want to measure the inductance of a coil, don't buy an inductance meter, rather take a resistor from your stock, connect it to the inductor, connect the sig-gen to the outer side of the resistor and the outer side of the inductor and excite it with sine waves; connect oscilloscope common to centre connection of R and L, and probes are connected to outer R and outer L. Adjust frequency of sig-gen until voltages across L and R are the same; measure the frequency (either from sig-gen dial, or multimeter depending on what accuracy you need), and calculate what the inductance value is... it is dead simple and keeps your brain ticking over remembering the fundamentals of your profession.

Another example of keeping your brain in trim is when you want to measure very small currents; you can use a voltmeter as an ammeter (yes your favorite Fluke multimeter), because you know (or you can measure) what the internal impedance of the voltmeter is... use your brain rather than throw money at expensive instruments that you may only need to use once!

We design and manufacture high voltage and current instruments, and the above ideas have taken us a long way.

Check out this site if you are in need of such test equipment.

For computer-based instrumentation, check our www.ni.com/products (National Instruments)

For hand tools, check out http://www.techni-tool.com/

I have not used anything from National Instruments, but there are some good possibilities there. Techni-Tool we have used over the past 3 years and we have been very satisfied with the quality, service, and price.

Let's not forget that the surplus market is a good source for used scopes and other specialized equipment. I would skip the new cheap stuff on eBay and get something that is "obsolete" in the minds of a high end electronics firm.

50MHz should be a good rate for most signals, you won't need higher unless you're getting into very fast digital. I agree with the idea that you should have one benchmark meter so that you can calibrate the others. But a decent scope and a good DVM are all you'll probably ever need at home. Well, maybe a frequency generator. You can make a decent DC power supply from an old ATX supply from a PC if you don't want a lot of current.

Whatever you do, have fun with it.

3rd year EE student: Which Country. 3rd year -not semester - yourZIP?

My work and interests: Normally 3rd Yearis the busy time for learning-to curriculum!

kenetic sculpture: Maybe you could tell us .Totally new term.

re-purposing e-waste: Ripping IC's from E-Garbage and Tinkering?Creating? WOW How do you do that and EEgrades both?

Do you have a whole lot of n000 IC datasheets, m000 Circuit ideas. Get These first.

One comment about the DMM. If you are working with low-distortion AC signals then you do not need a TRMS meter. Most likely however you will be working with signals that are other than a low-distortion AC signal so you must get one that is TRMS.

I agree that most Fluke meters are fine but at a very high price. I have found a line of TRMS meters that have the Craftsman name to be very accurate with distorted AC signals. Most of these meters are less than $100.

If you are looking for an inexpensive oscope, check out www.picotech.com

They have a decent line of scopes that you can take in a laptop case. I bought one for my worksite and it performs OK.

Hi,

From work experience after graduating, I bought a Brymen TBM126 Clamp meter with an accuracy of +/- 1%, and a second hand Fluke 105B Scope-meter with Fluke 80i-100s for use at home and work. My employer has similar instruments. When I want best results based on my work scope I use the Fluke Scope Meter, otherwise, if I am trouble shooting or doing basic system checks I use the Brymen TBM126 clamp meter.

A Fluke scope-meter is tops, its got about everything an electrical engineer may need for good analytical results and graphing.

Cheers,

Ron