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Products => Test Equipment => Topic started by: gooseEL34 on May 19, 2016, 10:00:26 pm

Title: If my scope is 20 MHz, any reason to get a probe rated to 100 MHz?
Post by: gooseEL34 on May 19, 2016, 10:00:26 pm
Thanks
Tim
Title: Re: If my scope is 20 MHz, any reason to get a probe rated to 100 MHz?
Post by: Keysight DanielBogdanoff on May 19, 2016, 10:15:47 pm
The probe you get will effect your overall bandwidth.  100 MHz is probably more than you need with a 20 MHz scope. 

We actually had a blog post a few weeks back that talks about calculating the system bandwidth: https://keysightoscilloscopeblog.com/2016/03/30/what-is-oscilloscope-system-bandwidth-and-how-do-i-find-it/
Title: Re: If my scope is 20 MHz, any reason to get a probe rated to 100 MHz?
Post by: tautech on May 19, 2016, 10:41:47 pm
Quote from: gooseEL34 on May 19, 2016, 10:00:26 pm
Thanks
Tim
Just get a pair of these:
http://www.ebay.com/itm/Two-P6100-DC-100MHZ-Oscilloscope-Scope-Clip-Probe-100MHz-For-Tektronix-HP-DY-/262248944156?hash=item3d0f41521c:g:2scAAOSwezVWup1c (http://www.ebay.com/itm/Two-P6100-DC-100MHZ-Oscilloscope-Scope-Clip-Probe-100MHz-For-Tektronix-HP-DY-/262248944156?hash=item3d0f41521c:g:2scAAOSwezVWup1c)

You can't go wrong unless your scopes input capacitance is some crazy value outside the probes range of adjustment.  :scared:
Title: Re: If my scope is 20 MHz, any reason to get a probe rated to 100 MHz?
Post by: saturation on May 21, 2016, 12:33:50 pm
Quality control on those no name probes can vary so best to get the higher MHz rated one.  Also, a 60MHz and 100 MHz probe from no-name are essentially the same price, and for use at 20MHz both work very well as the Keysight document explain. If you are diligent on eBay you could find even higher rated probes for less money if you buy more than one.  I bought a box of 4+ some years ago for ~ $20 as day-to-day banger probes; the construction could be iffy, but most of those in the box are still alive; I think we posted tests on eevblog forum some years ago.

https://www.eevblog.com/forum/reviews/cheapest-100mhz-oscilloscope-probes-hands-on-review/msg100171/#msg100171 (https://www.eevblog.com/forum/reviews/cheapest-100mhz-oscilloscope-probes-hands-on-review/msg100171/#msg100171)