Author Topic: scope pick up  (Read 707 times)

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Offline m3vuvTopic starter

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scope pick up
« on: July 26, 2020, 08:55:19 am »
not sure if this is the rite place to post but here goes,ive 3 scopes,one is a tek 453,also a kenwood dso and an old heath computer dso,on all 3 when i touch the probe tip with my finger i get a trace that measures about 200volts,it does this on all 3 scopes!,its still the same with a 10x probe on 10x or 1x,is that sort of reading normal,or is my house wiring iffy?,cheers m3vuv.
 

Offline bd139

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Re: scope pick up
« Reply #1 on: July 26, 2020, 09:31:02 am »
It’s completely normal.
 

Offline m3vuvTopic starter

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Re: scope pick up
« Reply #2 on: July 26, 2020, 09:49:37 am »
what its normal for it to read several hundred volts?
 

Offline bd139

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Re: scope pick up
« Reply #3 on: July 26, 2020, 10:01:27 am »
Yep.

I can't remember the precise mechanism but you're basically a current source with a high compliance voltage and the input is high impedance so it'll show much higher voltage than you might expect.

Here's mine. Yes 214 p-p volts.

 

Offline m3vuvTopic starter

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Re: scope pick up
« Reply #4 on: July 26, 2020, 11:03:29 am »
ok cheers for that,learn something new every day,cheers,m3vuv.
 

Offline magic

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Re: scope pick up
« Reply #5 on: July 26, 2020, 06:14:13 pm »
You are a capacitor :P

(okay, one plate thereof)
 


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