Differiential Probes - looking for schematics

[Kripton2035]

Differiential Probes

Hello,

I am searching for schematics of differential probes (for high voltages not referenced to ground like power supplies or tv monitors).
I found one in an elektor article (july 94) which fills my needs.
but I'm looking for other schemetics to compare before going into building one.

thanks in advance.

 

[Cluricaun]

Diffferentioal Probe

Hi

I have some schematics of differential probes, no active ones but capable of up to some kV, they are Chech language but the sch is easy to understand.

I am interested to check yourdesign from elektor, is it possible to send it to me.

PM me if you like to have the articles.
ANd the articles are quite big so if you have some place to UL to then tell me.

 

[Kripton2035]

not enought points I suppose !
Here is the article from elektor. hope it's helps you.

may be you can upload your schematics to the board **broken link removed**

and tell me where you put them.
thanks in advance.

 

[Cluricaun]

D Probe

Hi

I hope here will be something usefull, both old ordianry 100x1 probes and active and diff. But I do not know if there are any active diff probe but check and take what you need. The old heathkit files are mostly of historic interest.

I managed to compress and delete unusefull pages in the PDFs so I UL here instead.

If you build any of the designs and they are useless or excellent please tell. Some day I perhaps will build them too.

Good luck

 

[Cluricaun]

Link

Hi

Just found some articles thats interesting (perhaps), I have not been able to check them out. Something wrong with my browser.

123.ewh.i456.org/sb/iiee/tutorials/etm.htm#oscilloscope

123= you know
456=3*e

Hope you find anything usefull

 

[flatulent]

use oscilloscope controls

You can always use the invert and add controls on your oscilloscope. Start with two identical probes rated for the signal voltage you are to measure. Put one scope chanel on invert and put the vertical mode on add. Then put both probes on one of the lines and fine tune the gain of one of the chanels for zero deflection on your scope. (This will make both paths equal and improve the common mode rejection) Then put each scope on the terminals you want to measure. The ground leads of the probes should be connected to some point, such as ground during the above procedure.

 

[Kripton2035]

thanks everyone!

 

[jinny]

You can use Burr-Brown( it's TI now) differential instrumental amplifiere INA-117 if you want to measure up to 200v input signal and if you are working with low frequencies
[https://focus.ti.com/docs/prod/productfolder.jhtml?genericPartNumber=INA117]
If you'll need to measure higher voltages, you can add external resistors,
taking into account internal resistors of this chip.
INA-117 provides good CMRR.