Updating this thread:
I can read the LF side of the NExT fairly reliably using lf search to detect the EM card details as below however only with the Proxgrind LF Medium Range Antenna (from Lab401).
lf search
[usb] pm3 --> lf search`
[=] NOTE: some demods output possible binary
[=] if it finds something that looks like a tag
[=] False Positives ARE possible
[=]
[=] Checking for known tags...
[=]
[+] EM 410x ID 7130004189
[+] EM410x ( RF/64 )
[=] -------- Possible de-scramble patterns ---------
[+] Unique TAG ID : 8E0C008291
[=] HoneyWell IdentKey
[+] DEZ 8 : 00016777
[+] DEZ 10 : 0805323145
[+] DEZ 5.5 : 12288.16777
[+] DEZ 3.5A : 113.16777
[+] DEZ 3.5B : 048.16777
[+] DEZ 3.5C : 000.16777
[+] DEZ 14/IK2 : 00486136627593
[+] DEZ 15/IK3 : 000610086716049
[+] DEZ 20/ZK : 08140012000008020901
[=]
[+] Other : 16777_000_00016777
[+] Pattern Paxton : 1897168777 [0x71147F89]
[+] Pattern 1 : 34307 [0x8603]
[+] Pattern Sebury : 16777 0 16777 [0x4189 0x0 0x4189]
[=] ------------------------------------------------
[+] Valid EM410x ID found!
[=] Couldn't identify a chipset
With the standard Proxmark combined LF/HF antenna it’s very difficult and I have never been able to read the NExT with the ProxLF antenna which seems strange since this should be the ‘best’ option.
All of my LF antennas can read the bundled T5577 card (both lf search and lf t5 detect) which came with the Proxmark so do I assume the LF antenna in my NExT has some kind of problem?
I’ve also confirmed my T55xx device config is set to the defaults per this post.