http://ww1.microchip.com/downloads/en/A … 00710c.pdf
This is far too complex using this paper for doing antennae but at least it can help some people to understand the principle.
On my side, for a reader, a 4 turns antenna (3x3cm antenna), or 3 turn antenna (4x4cm antenna) is good enough to do the antenna of about 1µH +/-0.3µH. Then after this is just a tuning job with capacitors. Q factor can be adjusted with a parallel capacitor to the coil
For a card antenna, this is depending on the capacitor integrated in the chip but most of the time, the coil is around 3-4µA
]]>Cheers,
Roel
]]>Just to let everyone know who is interested. This weekend I will be working on "How to design and build an antenna for the Proxmark 3 device" for this community. - I will be building a bunch of them for some clients so I can take pictures and write down all of the crazy RF equations that I love, hehe.
I will post it on the forums when it is done! If anyone wants to help, shoot me an e-mail !
Cheers,
]]>These HOWTO's should become available within a few weeks. But any help will appreciated.
Cheers,
Roel
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