Sensitivity of the current probe and oscilloscope combination too low

[Kiriakos GR]

Here comes an interesting find from the side of Rohde & Schwarz GmbH
At their fresh R&S®RTB 2 Oscilloscope series (Date 10-2025), there is a special note at product specifications.

Trigger sensitivity -> input sensitivity < 2 mV/div with HF reject (filter ON).
This translates that either and this 10bit modern design, it requires High Frequency Reject filter, all times, when lowest Volt/Div this is selected.
   
Pico TA189 probe..
An 100mV/A probe, when this measuring low current of 10mA AC, it mV output this gets very low.
500mA = 50mV
50mA = 5mV
10mA = 1mV (RMS) and or 3mV PP.

For some time I thought that my hidden problem could be my own scope front-end sensitivity.
But now I gained confidence that even recent production of scopes, this also strangles to get a good trigger at lowest Volt/Div.

I did test HF reject at my GDS-2102A, it does work!, and it does deliver a noticeable improvement.
My DUT is copper transformer under load at 240V.
Now I can measure as low as 10mA  with good stability and repeatability.
But this low 1mV output of the probe, this is not enough so the oscilloscope to deliver a free of noise waveform. 

       

[Kiriakos GR]

Another interesting piece of information this found today in Asia.

This is relative to 200mV/A probe (AC/DC), that is double the output from 100mV/A.
This tool delivers at 1mV output at 5mA as best. 

At offered accuracy specifications, the Chinese starts counting from 30mA~5Apeak at 200mV/A.
While it best as tight accuracy this is at 3%. 

From the side of Europe (France), there is also available an 200mV/A probe ACA only.
Tight accuracy this is at 3%

In conclusion, Pico TA189 probe (Germany + UK engineering), this wins again first position, of anything else out there.
And if you add two turns coil splitter this will be able to measure down to 5mA in the screen of one oscilloscope.

Even at 2026, current clamp probes with 1000mV/1A (1V/A) output they are considered as a luxury product.
Yes these are Japanese engineering, but 99.99% of electrical applications will not need such a tool. 
But I will accept the fact, that such probes, they will deliver a nicer and cleaner current waveform, for you to review at your oscilloscope.

This ITTSB article, offered to you all known information's regarding the world of quality current probe and Oscilloscopes.
In Europe, we should feel lucky, having this Pico TA189 (class of product engineering) in our toolbox.
Even today, China this is unable to compete at that sector, getting a cheap probe this be 10 times worst in everything, this is not a reasonable decision.