csearle wrote:This is almost exactly the answer I was about to post. A small gap at such frequencies is just another way of describing a capacitor, which is a device frequently used in series along the RF signal path for various reasons including decoupling the DC biasing point of one stage of the electronics from the next.SteelCamel wrote:XFool wrote:But the aerial has to connect to the chip and the RFID chip is combined with the Chip & PIN chip, there is only one chip per card. So isolating the chip from its surroundings ought to work and, as per my later post, I have now definitely scored through two pieces of copper at the top of the chip connector. I suspect my first attempt with the knife didn't go far enough in.
At radio frequency, it doesn't need to connect as in be physically touching. RF signals can easily jump small gaps. So if you've cut the wires but the cut ends are only microns apart, the RF signal will go through almost as if there was no cut. You need to make a wider cut to block RF signals - I don't know how wide it needs to be, but if there's no visible gap it's almost certainly not wide enough.
Seems to me like a totally pointless exercise anyway. The interlocutor has to be very close; and anyway the banks are so very keen to promote their stuff that in my experience any fraud of any kind is almost immediately refunded.
C.
"Improve DC noise rejection via AC coupling using a scalpel" has the ring of a Practical Electronics article from the 70s
I can imagine it in the middle of this: https://worldradiohistory.com/UK/Practical-Electronics/70s/Practical-Electronics-1978-01.pdf