messed up relative compression wave form, what is wrong?

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jarrod27
Newbie
Posts: 5
Joined: Sun Nov 27, 2011 4:53 pm

messed up relative compression wave form, what is wrong?

Post by jarrod27 »

what is going wrong here is it the settings, the scope, or the amp probe, it is all brand new on pre settings. Image

jarrod27
Newbie
Posts: 5
Joined: Sun Nov 27, 2011 4:53 pm

Re: messed up relative compression wave form, what is wrong?

Post by jarrod27 »

Even with the filter on the wave form still has the long tails. thanks

Alan
Pico Staff Member
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Joined: Thu May 25, 2006 8:02 am

Re: messed up relative compression wave form, what is wrong?

Post by Alan »

That an interesting / odd waveform (which is a way of admitting I don't know the answer). Two possible guesses, the first is a loose connection from the clamp to the BNC connector on the PicoScope causing the signal to drop out - check turned / not loose. The second would be a loose connection on the vehicle - perhaps battery terminal.

Can you recapture but add channel B as battery voltage and then post again - I want to see if the battery voltage jumps up a bit when the current drops out. Best to post the screenshot as you have an the .psdata file for this one.

mapengo
OneWave
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Location: Warrington, Cheshire

Re: messed up relative compression wave form, what is wrong?

Post by mapengo »

Try your scope in a different USB port Jarrod.

Doc...

MAE
OneWave
OneWave
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Joined: Wed May 01, 2013 7:16 am

Re: messed up relative compression wave form, what is wrong?

Post by MAE »

I thought i would jump on this post(hope you dont mind) as i am experiancing a similar problem, just purchased a pico advanced auto kit, i get the same thing on a battery test or comp test, have the same issue in pico scope software even connected to a battery sitting on the floor totally away from a vehicle i get erratic waveform. I have tried differant laptops, test leads and software versions. only thing i haven't subtitued is the pico(for obvious reasons). Does the pico team have any advice on this? i have been in contact with my supplier in australia and they currently dont have an answer

Lee
TwoWaves
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Posts: 79
Joined: Fri Feb 19, 2010 10:36 am

Re: messed up relative compression wave form, what is wrong?

Post by Lee »

Is your laptop plugged into mains, could be noise through charging system within laptop.

Have you tried with laptop not plugged into mains?

Kind Regards

Lee - LMH Engineering Services :D

MAE
OneWave
OneWave
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Re: messed up relative compression wave form, what is wrong?

Post by MAE »

Tried plug and unplugged. No difference

Martyn
Pico Staff Member
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Location: Cambridgeshire

Re: messed up relative compression wave form, what is wrong?

Post by Martyn »

Does it happen on any of the channels, or just one ?

Which software version are you running ? Help->About to Cut and Paste the Text
Martyn
Technical Support Manager

MAE
OneWave
OneWave
Posts: 20
Joined: Wed May 01, 2013 7:16 am

Re: messed up relative compression wave form, what is wrong?

Post by MAE »

Haven't tried channel 3 or 4 yet but defiantly both 1 and 2

I tried the current version as of Tuesday last week and the earliest available version on the web page

Martyn
Pico Staff Member
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Posts: 359
Joined: Thu Aug 11, 2011 7:43 am
Location: Cambridgeshire

Re: messed up relative compression wave form, what is wrong?

Post by Martyn »

and are you using the supplied blue USB cable directly between the scope and the laptop ?
Martyn
Technical Support Manager

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