NewAE H-field probe design

[ifrenide]

Hello, I want to know 2 things about the newAE H-field probe,
1-why they use 4 layer PCB , while it is possible to make it with 2 layers .
2- In layer 2 , is there any contact bitween the 1mm track  " the end of the ring"and the copper area ?
best regards.

[ifrenide]

is there anybody to help me here?

[DaJMasta]

It's been half an hour, just waiting a bit will yield better results.

It's a 4 layer PCB because if you made it with two layers the entire track before the loop would act as an antenna and otherwise mess with the response of the probe, even holding it would effect readings significantly.  With four layers, the outer layers (you only really need 3, but 3 layer boards are uncommon) act as a shield, and when stitched together with vias, effectively create a coaxial cable within the board (the signal track is surrounded by grounds).


The track on layer two is stitched to the connector center pin pad on the top layer with vias on the left of the image.

[Bud]

Such a flat fat probe would be awkward to use, wouldn't it be 

[ifrenide]

no problem at all when we use it, and we cab cover it to make it a litle bit proffessional

[ifrenide]

why there is a connection between the track and copper area of layer 2 and other connection between this truck and  the other layers using vias ?

[LazyJack]

How would the circuit be closed otherwise, if there were no connection with the ground there?

[TurboTom]

For better sensitivity and common-mode (E-field) insensitivity (especially for the very small H-Field probes), the "professional" ones use a symmetrical output of the pickup turn, often also a two-turn design with a mirror-shape turn on the second inner layer, and a tiny, SMD balun close to the connector.

[EE-digger]

It's nice to see an SMA on the real product.  Other probes lean toward connectors which can rotate (like SMB), which is convenient, but not so nice if you're driving it from an RF power amplifier for immunity testing ... and the connector unplugs