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Question for any of you who might be into electronics

FreejackFreejack Jake the Not-so-Wise
in Zocalo v2.0
Have you ever tried one of the PC-based ocilloscopes like [url=http://polly.phys.msu.su/~zeld/oscill.html]this one[/url]?

I need to test the signal outputs from a variety of vehicle speed sensors and I do not have the access to a true scope. I need to determine whether the output of the speed sensors that I'm testing is a sine wave or a square wave...

Jake

Comments

  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    If you just need to see if it's a sine wave or square wave, even the cheap software ones should do the job. Pay attention to the maximum frequency they support, though. Make sure the signal you're planning on measuring is within that range.
  • the_exilethe_exile Kupo!
    One a semi-not-at-all-related topic, what is a cephaloscope? It's been bothering me since I read [i]A Scannery Darkly[/i] way back when.
  • FreejackFreejack Jake the Not-so-Wise
    [QUOTE][i]Originally posted by Biggles [/i]
    [B]If you just need to see if it's a sine wave or square wave, even the cheap software ones should do the job. Pay attention to the maximum frequency they support, though. Make sure the signal you're planning on measuring is within that range. [/B][/QUOTE]

    I don't think frequency will be a problem, given that one of the manuals I have specs the VSS signal at 125hz at 55 miles per hour...

    Jake
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    The cheaper PC-based scopes tend to go pretty low for their maximum frequency, but not that low. :) Still, keep in mind that with PC-based scopes you very much get what you pay for. The cheap ones tend to be average quality at best, and often have horrendous user interfaces. There was a review posted on slashdot earlier this year about a few of the common PC-based ones, it could be worth hunting that down.
  • PSI-KILLERPSI-KILLER Needs help
    I am curious how you would hook probes up through the sound card.
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    The sound card? I guess you could connect them to the line in socket. But soundcards have very low sampling rates compared with oscilloscopes.
  • bobobobo (A monkey)
    [QUOTE][i]Originally posted by the_exile [/i]
    [B]One a semi-not-at-all-related topic, what is a cephaloscope? It's been bothering me since I read [i]A Scannery Darkly[/i] way back when. [/B][/QUOTE]
    [URL=http://dictionary.reference.com/search?q=cephalo]Cephalo[/URL] means "head", so by definition, a cephaloscope measures heads. :D
  • the_exilethe_exile Kupo!
    [url]http://dictionary.reference.com/search?q=cephalometry[/url]

    I guess it would make sense in the context of the book if it were used to measure brain waves or some such.
  • E.TE.T Quote-o-matic
    [QUOTE][i]Originally posted by Biggles [/i]
    [B]Make sure the signal you're planning on measuring is within that range. [/B][/QUOTE]Works if you want to measure frequency.
    But when you want to see waveform you need couple times bigger sampling rate than frequency of measured signal. (actually with double sampling rate you would only see half-waves)

    But if frequency is in 100-200 Hz range then I don't think sampling rate will be problem.


    [QUOTE][i]Originally posted by bobo [/i]
    [B][URL=http://dictionary.reference.com/search?q=cephalo]Cephalo[/URL] means "head", so by definition, a cephaloscope measures heads. :D [/B][/QUOTE]That reminds me about one thing...
    Search for thick-headed lizard (/reptile) in Google! ;)
  • FreejackFreejack Jake the Not-so-Wise
    [QUOTE][B]Works if you want to measure frequency.
    But when you want to see waveform you need couple times bigger sampling rate than frequency of measured signal. (actually with double sampling rate you would only see half-waves)

    But if frequency is in 100-200 Hz range then I don't think sampling rate will be problem.
    [/B][/QUOTE]

    Its a rotory speed sensor, so I should be able to spin it to the required frequency. 125hz is about 1000 rpm on a 8 pulse per rev sensor....

    Jake
  • SpiritOneSpiritOne Magneto ABQ NM
    Ive never used a PC scope before so I dont know what to expect with one. I use scopes mostly to deal with RF signals and the digital scope that I have (Fluke 199C/M) can be kind of flakey with RF sometimes, an analog scope would be preferred. Unfortunately there arent that many portable true analog scopes out there.

    Just make sure you dont try to measure something that would damage your sound card, like a high current object. Im not familiar with vehicle systems, so I dont know what to tell you not to measure.
  • E.TE.T Quote-o-matic
    [QUOTE][i]Originally posted by SpiritOne [/i]
    [B]Just make sure you dont try to measure something that would damage your sound card, like a high current object.[/B][/QUOTE]More like voltage... max current output doesn't matter if there's not enough voltage "pushing it".
  • FreejackFreejack Jake the Not-so-Wise
    Voltage should not be a problem, since these sensors are made to hook up to a engine control computer in the first place. I believe these produce 5.5VDC max on the signal wire.

    Jake
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    The PC-based scopes don't usually use the sound card. They usually have either a special signal capture card or a USB device that captures the signals.
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    [QUOTE][i]Originally posted by SpiritOne [/i]
    [B]...an analog scope would be preferred. Unfortunately there arent that many portable true analog scopes out there. [/B][/QUOTE]

    Pats his Analog Tek 30Mhz Dual Trace...

    ;)

    :D
  • SpiritOneSpiritOne Magneto ABQ NM
    I also need it to be a 200Mhz scope or better.:(
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    I wish I could afford one of the scopes we have at uni. Beautiful analog/digital scopes that go into such high frequencies we can't even beat them with the uber-signal generators.
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    My 30 Mhz dual trace is more than adequate for my simple electronics and stuff.

    Audio, TTL, and 11 meter 2-way is accessible easily with it... that and my frequency counter too...

    My multimeter has all the other possible things like freq counter, diode/transistor test, cap/inductance, etc

    can't wait to get back into this stuff when we've moved.

    :D
  • PSI-KILLERPSI-KILLER Needs help
    I sold a few ocilloscopes in my short time.
    Talking just benchtops
    a 20 mhz scope analog can go for 477.00
    a 2+16 channel 500mhz analog/digital scope can go for 10,000

    They all have warrenties a certified accuracy.

    With this sound card thingy solution you could possable damage your sound card or your motherboard!! Where is your savings with a voided warrenty?

    I looked into PC based ocilloscopes, you can actually buy a brand new one for $150.00 U.S. Dollars. To me if you are going to be doing this allot it might be worth the investment. Plus if you have customers see you using a sound card with ad hoc probes to measure stuff, what is up with that??? Since video cards are going for $600 a $150 is allot less. Plus the GUI is allot better, just as good as a "high end" scope.

    l
    trade ink below


    [url]http://www.embedded.com/shared/printableArticle.jhtml?articleID=160902529[/url]
  • FreejackFreejack Jake the Not-so-Wise
    I currently watching a analog scope on ebay that's just down the road from me, any idea if this would work for my use?

    [url]http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=7539152111&rd=1&sspagename=STRK%3AMEWA%3AIT&rd=1[/url]

    Jake
  • PSI-KILLERPSI-KILLER Needs help
    For 25.00 bucks that is not bad
  • SpiritOneSpiritOne Magneto ABQ NM
    for what you want to do, and for $23.50 its a steal. Tektronics makes good test equipment. This should be a good scope if its been taken care of.

    Id like to see a few more pictures of it, make sure its not banged up or anything, but its a good scope.
  • PSI-KILLERPSI-KILLER Needs help
    It is going up. 36.00 now. Don't forget you would probaby need to get it calibrated.
  • PSI-KILLERPSI-KILLER Needs help
    Who is testeqe ?

    I am maximiza was not me.
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