H-field probe of CW capture rev2 gives only noise :(

Hi everyone,
I’m using the H-Field probe that comes with the CW capture rev2. I didn’t find any tutorial on the internet on that. Only a tuto on a newer version H-probe.

The problem is when I put the H-probe on the ATMega 328P of the CW301 Multitarget board running an AES Software there is only noise. I raised the gain but still nothing.

Does anyone already used this H-probe ?

What should I check?


How are you evaluating the noise? The signal may look noisy, but the SNR may be high enough to still do an attack. You may also need to move the probe around as well.


Here are the power traces that I get when I used shunt resistor and when I use the H-Field probe. When I move the probe on the ATMega I get the best signal at the middle of the die. I will capture about 300 traces and try to do the attack.

Here is the power traces with H-probe when I raise the gain