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Fluke 87v v. 28-II

  1. Jan 25, 2010 #1
    I am an electrical engineering student and I want to buy a good multimeter. Can anyone recomend on of these two models or tell me what the primary advantages of each on is?
     
  2. jcsd
  3. Jan 25, 2010 #2

    f95toli

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    Well, the 87v is a True-RMS multimeter whereas the 28-II isn't (as far as I can tell).

    That said, is there any particular reason you want to buy a "high end" multimeter? 9 times out of 10 a cheap(ish) model will be enough. And when one ISN'T good enough you should probably use a benchtop multimeter anyway (in order to be able to do 4-point measurements etc).

    Don't get me wrong, I use Fluke multimeters all the time at work and they are great; but I would never buy one to have at home; and I NEVER use one for anything "serious".
     
  4. Jan 25, 2010 #3

    turbo

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    For a student, the current equivalent of the Extech 22-816 (I think they are discontinued) should be more than adequate. It's a true RMS meter with lots of features and capabilities. I picked mine up years back at Radio Shack with test leads, temperature probe, and armored case for less than $60. It's actually way over-kill for my applications, though deteriorating capacitors in old tube amps is a frequent problem and I needed a meter that could measure capacitance, which my old one did not do.
     
  5. Jan 25, 2010 #4
    Fluke 87v is a professional industrial multimeter. It's sure a good investment. It will last you more than 10 or 20 years, and give accurate readings.

    But like with anything else you buy, you have to ask yourself what will you use it for? Most people get Flukes because they are making a living out of them. Their job depends on them.


    As an alternative, check out the Meterman 37XRA:

    http://www.globaltestsupply.com/c/181/Amprobe_Meterman_37XRA_True_RMS_Digital_Multimeter.html [Broken]

    It's True-RMS, and rugged.
     
    Last edited by a moderator: May 4, 2017
  6. Jan 25, 2010 #5
    Flukes are generally expensive, but great meters. As for True-RMS, few people actually need that feature. Any meter will give you RMS for a "standard" sine wave signal. (By "standard," I mean that one cycle consists of a positive and equally negative wave with respect to amplitude and width. Also, the wave repeats at a steady frequency.)
     
  7. Jan 25, 2010 #6

    dlgoff

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    I built my first multimeter and still use it. Here's a kit that you might want to consider.
    http://www.electronickits.com/kit/complete/meas/ck105.htm" [Broken]
     
    Last edited by a moderator: May 4, 2017
  8. Jan 25, 2010 #7

    berkeman

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    I still remember the old joke (from another analog guy that I used to work with)... "If it works, it's a Fluke!" :rofl:

    One feature you might look for (I didn't check the two meters you listed), is the ability to make simple capacitance measurements. I have a separate LCR meter that I use most of the time, but use the feature on my Fluke 179 DVM occasionally. My 179 also has a sumple frequency counter feature that I use occasionally when I don't have an oscilloscope handy.

    I also like it when the diode check feature uses a large enough open circuit voltage to slightly light up an LED.
     
  9. Jan 25, 2010 #8

    turbo

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    Capacitance, frequency, and RMS evaluations of noisy signals all got me to spend a few extra bucks on the Extech. I had several basic DMMs, including a pocket model, but I needed to be able to evaluate old (possibly dried-out) capacitors in guitar amps. I used to work on Fenders a lot, and Leo was not known for buying top-shelf components. If you use those old amps regularly, the filter caps can last a long time. Long periods of inaction can accelerate the degradation. Old amps can look wonderful, but sound like crap - check the caps.
     
  10. Jan 25, 2010 #9
    I think capacitance will not really tell you the condition of the capacitor accurately. For that there is an ESR meter which measures internal resistance of a capacitor. Alot of bad caps can look fine and show good capacitance, but still can have high ESR.
     
    Last edited: Jan 25, 2010
  11. Jan 25, 2010 #10
    One of my profs used to say that to a class. All the students had blank stares. I replied "77 or 87?"
     
  12. Jan 25, 2010 #11

    berkeman

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    :tongue2: :rofl:
     
  13. Jan 25, 2010 #12

    turbo

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    Probably true, but the meter helped me weed out the dogs. Look at a Fender guitar amp schematic to see what I mean. Bulk replacement was not always necessary. I had one customer that wanted me to peel the paper covers back from old caps and use them to cover the smaller more modern caps. I refused, and told him to take his business elsewhere. He relented, and got some nice bright Astrons instead. I had removed enough stupid mods from his vintage amps and got them singing again that he chose pragmatism.

    There was nobody else within 100 miles or more that could restore his collection. He and I attended a guitar show 100 miles away in Portland, and I had a number of my restored or home-built amps available for try-out. Before the day was over, I had a pretty prominent studio-owner (who does mix-downs for top acts, among other things) and the owners of a couple of the state's largest music stores offering me all their tech-work. My buddy was pleased, but not surprised. Ain't no way I'm going to restore tube amps for some store 100+ miles away unless they are willing to pay crazy money for the work. They'd have to hire some pizza delivery-kid just to shuttle the work back and forth to make that work.
     
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