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Hi All,
I have an unusual scenario. I have a "clamshell" card, I suspect is t55xx.
I am trying to read it at 125kHz, however, I do get a strange plot. It looks as if the signal is "saturated".
https://imgur.com/hYURGxq
I then read the card at 14.5 cm, and the "saturation" disappears.
https://imgur.com/qRw1gEB
I do understand that just because the card is "clamshell", does not mean absolutely that it is 125kHz, so as a test, I read a Mifare classic card ON the antenna at 125kHz and the plot looks very similar!
https://imgur.com/K4gzaMU
I have tried reading the "clamshell" on 13.56MHz, at varying heights, however, it is not recognised!
Do I have a bad card?
What else could I try to read the card?
I am missing something obvious?
Many thanks to All!
Last edited by PM3PVM (2020-03-05 21:32:49)
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Looks like you have a ton of interference. Is your antenna connected properly? does the voltage register okay? Have you tried moving your entire proxmark to a different area?
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Many thanks, @Marshmellow for your reply.
Firstly to answer your questions;
Yes, the antenna would appear to be connected correctly. I can read other 125kHz cards fine.
Voltage seems ok;
[usb] pm3 --> hw tune
[=] Measuring antenna characteristics, please wait...
[=] You can cancel this operation by pressing the pm3 button
..
[+] LF antenna: 20.49 V - 125.00 kHz
[+] LF antenna: 11.69 V - 134.83 kHz
[+] LF optimal: 23.51 V - 127.66 kHz
[+] LF antenna is OK
[!] HF antenna is UNUSABLE
[+] Displaying LF tuning graph. Divisor 88 is 134.83 kHz, 95 is 125.00 kHz.
[usb] pm3 --> Yes, I have tried other areas, orientations, and different distances from the antenna.
Is there anything else I can do to reduce and or eliminate "interference" as a factor?
Furthermore, to help me (and of course others reading the thread), what is it that you see in the trace that makes you say "Looks like you have a ton of interference"?
Again, many thanks for your help.
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