Author Topic: Fluke 95 Oscilloscope Sampling  (Read 3493 times)

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Offline Tony R

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Fluke 95 Oscilloscope Sampling
« on: September 26, 2011, 12:22:59 am »
So i was browsing the pages of ebay and i found an add that got me a little confused and hope some of you guys can help clear it up for me

I found a Fluke 95 50 Mhz hand held scopemeter. in the add it stated "*** 50 Mhz Dual Channel *** 25 Megasamples/second ***"

Now when taking signals and systems i was always told that your sampling frequency must be at least twice the frequency of the signal you want to sample so fs>= 2*f.

So if this is sampling 25 million times a second, how can it be rated for 50 MHz waves?
Tony R.
Computer Engineering Student
Focus: Embedded Assembly Programming, Realtime Systems,  IEEE Student Member
 

Offline Zero999

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Re: Fluke 95 Oscilloscope Sampling
« Reply #1 on: September 26, 2011, 12:32:16 am »
It'd possible to have a higher analogue bandwidth than double the sample rate for repetitive waveforms.
 

Alex

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Re: Fluke 95 Oscilloscope Sampling
« Reply #2 on: September 26, 2011, 12:35:34 am »
Ahh, used to have that one!

Sure, look up equivalent time sampling. Here is a dcent app note:

http://www2.tek.com/cmswpt/tidetails.lotr?ct=TI&cs=Application+Note&ci=14295&lc=EN
 

Offline saturation

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Re: Fluke 95 Oscilloscope Sampling
« Reply #3 on: September 26, 2011, 08:51:12 pm »
2x is minimum, realistically its 10x.  So that scope is effectively 2.5 MHz worse case, in single shot applications.
Best Wishes,

 Saturation
 


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