Amal, here’s the inside of my bus card, seen against a 1.5 kW projector shining through it. The blob on the upper right (dim. 8.1 x 5.3 mm) is a DESfire EV1, and the antenna goes all around the card (i.e. it’s not a mini card thing).
I know you are specifically asking Amal and No real point answering you since you will wait for Amals reply anyway
, however I may be able to help a little… since I have sent him 2 cards for conversion.
For what it's worth
One of mine was also a DESFire EV1 transport card
The dimensions appear to be the same
If it has “wings” it will make attaching the antenna viable, it is hard to discern them in your image but it looks like it to me
NXPs TagInfo will return 17pF capacitance which is suitable for Amals antennas
So in my opinion YES looks viable.
Send it to him as is, not like this idiot who sent him the exposed chip
Did your transport authorities get back to you or are you just getting your ducks lined up ?
I think that is a standard response from the app rather than measured, but yeah I would be pretty confident to get it in the mail to Amal, although I’m sure he will be along in a few hours to confirm for ya all proper like
I think it’s likely this can be converted. Amal has a bunch of antennas on hand, most of which are tuned for common NXP input capacitances like 17pF. Then it would just come down to how easy it is to dissolve the card and what package/condition the chip is in.
Not sure how easily it’ll dissolve in acetone, but one thing is certain: the plastic is kind of crap. I held it 15 seconds tops in front of the projector, it got barely warm, and that was enough to warp the shit out of it. I straightened it out, but now it feels like it has lost half of its structural strength.
It would not survive one hours on a hot dashboard in the middle of summer - but that doesn’t seem to be a very common problem in Finland
the df ev1 package is much smaller than a mob packaged IC like @Pilgrimsmaster showed… so my concern is that it is potted silicon instead of a mob package… that would be a very difficult thing to convert.
yeah that’s true for known situations, but this is an unknown and rather than you waste $ sending to me to find out it’s not going to work… I figured you are meticulous enough to get it done without damaging the thing.