Help buying an oscilloscope

Discussion in 'General Electronics Chat' started by adam555, Aug 24, 2013.

  1. adam555

    Thread Starter Active Member

    Aug 17, 2013
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    Hi again,

    I've decided to buy an oscilloscope, but I can't spend that kind of money on a new good one. So I only have 4 options:

    1) Buy a second hand one... but I don't find them near and cheap enough

    2) But one that connects to the PC... though I don't really like that idea, because I'm not experienced enough to make sure I won't blow up both.

    3) Buy a handheld one... I saw many between $50 and $100, which is the absolute maximum I can spend.

    4) Make one. :)
     
  2. adam555

    Thread Starter Active Member

    Aug 17, 2013
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  3. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
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    This one is twice the price of the one above, and also from ebay, but looks much better:
    [​IMG]

    That's all I could find these week on ebay for less than €100
     
  4. adam555

    Thread Starter Active Member

    Aug 17, 2013
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    Forgot to ask... what are the specs that I should look for on these handhelds?
     
  5. whatsthatsmell

    Active Member

    Oct 9, 2009
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  6. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
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    Thanks, I'm in Spain; which is probably making it more difficult.

    I look regularly on ebay, but can't get any decent one from less than €250
     
  7. strantor

    AAC Fanatic!

    Oct 3, 2010
    4,302
    1,988
    I've never shopped ebay from spain. I got my tektronix from an Ebay military surplus store for $100USD. It was ~10 years old, but had a certificate of calibration and looked like it had never been used before. I waited for a long time for a deal like that to come up. Sometimes people don't know how much something is worth, and the "buy it now" option reflects that.
     
  8. adam555

    Thread Starter Active Member

    Aug 17, 2013
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    I often buy stuff from ebay.co.uk, and can find some at good prices there, but they are either for pick up or won't ship to Spain. I guess it will be the same with ebay.com

    That why I'm afraid the handheld ones are the best option in my current situation; just that I don't know which specs I should look for.
     
  9. bountyhunter

    Well-Known Member

    Sep 7, 2009
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  10. Sensacell

    Well-Known Member

    Jun 19, 2012
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    Buy a nice used Tektronix scope, the 2236 is a nice starter scope for sure.
    You can find plenty for around $200.00

    When you get ready to upgrade, you can sell it for $200.00, then it was free...

    All those USB PC / handheld units are garbage, IMHO.
     
  11. adam555

    Thread Starter Active Member

    Aug 17, 2013
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    OMG... just been to the Tektronix website and saw an oscilloscope for $300,000!!! You can buy a house (or two) for that kind of money. The cheapest is $500, which is far too much for me.

    $200 I could make an effort to spend, but I doubt I'll find it for that money here in Spain. This is the cheapest desktop oscilloscope currently in ebay.es: a Siglent SDS1062C Digital Osciloscopio 60MHZ DS1052E from Hong Kong for $328

    [​IMG]
     
  12. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
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    One thing I need to add...

    I basically need the oscilloscope for learning and experimenting, not for anything serious. So I'm not sure if spending $200 just to play with it would be wise.

    This are the specs of the cheapest handheld, the oscilloscope kit for $33; what do you see on the specs that makes it unsuitable a beginner like me to play around with?
    •Max sample rate - 2M/s,8 bits
    •Sample memory depth - 256 bytes
    •Analog bandwidth - 1MHz
    •Vertical sensitivity - 100mV/Div - 5V/Div
    •Vertical position adjustable with indicator
    •Input impedance - 1MΩ
    •Max input voltage - 50Vpp
    •DC/AC coupling
    •Horizontal - 5μs/Div - 10m(minute)/Div
    •Auto, normal and single trig modes
    •Rising/falling edge trigger
    •Trig level adjustable with indicator
    •Hold/run feature
    •Built-in 500Hz/5Vpp test signal
    •Frequency counter features with independant F and T read-outs (only for TTL level input signal)​
     
    Last edited: Aug 25, 2013
  13. Austin Clark

    Member

    Dec 28, 2011
    409
    44
    The biggest problem with it that I can see is it's super small memory depth, and possibly a terrible display and interface. The small memory depth basically means you can't take advantage of the highest sampling rate when you're viewing waveforms over a longer period of time. You can at most store 256 plot points in any given time domain.

    I suppose it would be barely ok for the simplest of tasks, but not one I would recommend.
    Oscilloscopes are pretty much a must if you want to take electronics seriously, and good ones just don't comes cheap. I paid about $500 for mine, brand new.
    The first one I ever got was from my Uncle, and it required a parallel port on a computer. It left much to be desired, but it worked. The best part about it was that I learned how to use a 'scope and I knew what to shop for when I finally decided to buy a better one. Perhaps that would be the justification for buying such a cheap scope for now.
     
  14. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
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    I just realized I need one because I'm studying electronics again and I find it really difficult to do tests and experiments with any circuit that has any sort of sine wave. I just can't see if they are working or not.

    Not asking for much really, just something that would meet the most basic needs and allow me to advance.

    I don't want to put too much money into it for various reasons: first, I can't afford to spend too much on it; I don't know for how long would I be interested in electronics this time; I don't know if I'll be taking advantage of the advance features that a proper oscilloscope will provide; and I'm also very afraid of buying something expensive and damage it in any way due to my lack of knowledge and experience.

    So, unless I find a cheap one on ebay, I'm afraid I'm going to have to go for that kit or the next step (the small handhelds). Like this one:

    [​IMG]

    Specification:
    Display
    2.8 inch Colour TFT LCD
    Display Resolution
    320×240
    Display Colour
    65K
    Analog bandwidth
    0 - 1MHz
    Max sample rate
    1Msps 12Bits
    Sample memory depth
    4096 Point
    Horizontal sensitivity
    1uS/Div~10S/Div (1-2-5 Step)
    Horizontal position
    adjustable with indicator
    Vertical sensitivity
    10mV/Div~10V/Div (with ×1 probe)

    0.5V/Div~10V/Div (with ×10 probe)
    Vertical position
    adjustable with indicator
    Input impedance
    >500K?
    Max input voltage
    80Vpp (by ×1 probe)
    Coupling
    DC
    Trig modes
    Auto, Norma, Single, None and Scan
    Functionalities:
    Automatic measurement: frequency, cycle, duty, Vpp, Vram, Vavg and DC voltage

    Precise vertical measurement with markers

    Precise horizontal measurement with markers

    Rising/falling edge trigger

    Trig level adjustable with indicator

    Trig sensitivity adjustable with indicator

    Hold/run feature
    Test signal
    Built-in 10Hz~1MHz (1-2-5 Step)
    Waveform storage
    SD card
    PC connection via USB
    as SD card reader
    Upgrade
    by bootloader via USB
    Power supply
    3.7V Chargeable Lithium battery / USB
    Dimension (w/o probe)
    105mm X 53mm X 8mm
     
    Last edited: Aug 25, 2013
  15. DerStrom8

    Well-Known Member

    Feb 20, 2011
    2,428
    1,328
    DO NOT EVER BUY THE HANDHELD ONES! They're pure garbage. And Whatsthatsmell posted the exact video I was thinking of posting :p

    Check your local hospitals and universities. You can often find very decent analog ones for very cheap or even free (if you ask the right people). I agree with Dave Jones (from the EEVblog) that you can get away with a dual-channel, 20MHz model for most projects. It's a great starting one.

    Good luck!
    Regards,
    Matt
     
  16. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
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    I just realized that the specs of that handheld are practically the same as the $33 kit; so it's not really the next step, just double the money. :(
     
  17. DerStrom8

    Well-Known Member

    Feb 20, 2011
    2,428
    1,328
    Exactly. Besides, all the handheld ones I've ever seen just don't work well at all. Their resolution is horrid, they break easily, and they do not usually meet the specs provided. Just avoid them, whatever you do.

    Again, ask at your local hospitals and universities.

    I'd happily send you one of my old ones for just the cost of shipping, but 1) I still need it and 2) shipping would be very expensive....

    I'll let you know if I come across something, but in the mean time, follow the advice given and you might get lucky :)

    Regards,
    Matt
     
  18. Metalmann

    Active Member

    Dec 8, 2012
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  19. Metalmann

    Active Member

    Dec 8, 2012
    700
    223
    Then again, I'm sure I will be deader than poop, before I learn all the uses of this scope.:D
     
  20. adam555

    Thread Starter Active Member

    Aug 17, 2013
    858
    39
    I was thinking on getting the cheapest handheld (which is the kit) for now, while I keep on searching for a real one in the places you told me.

    And... if leave this hobby, break it, or buy a better one, it was just $33.

    By the way, I just found out you can easily make one with an Arduino; I would just need to buy the LCD screen. :)

    [​IMG]
     
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