Is it better or worse?
NXP is the best on the planet at what they do. I don’t expect we’ll ever see a magic chip match their performance–unless they start making them.
There’s a lot of factors that go into an RFID chip’s performance (separate from the coupling). There’s the quality of the analog frontend (and how well it’s matched to the antenna). There’s the quality of the energy harvesting circuitry that powers the logic. There’s the quality of the logic circuits themselves and how consistent they are with timings and emulation and such.
For magic chips they may have a leaked die map they modified or they may have hacked something together themselves from other products they make. Because it’s always gray market they’re not usually very high quality (even if the price is ridiculous). Getting a silicon etching facility (even in China) to do the small-medium batch stuff these magic chip suppliers want is expensive. Plus the bigger companies could patch whatever vulnerability they’re exploiting so they can’t afford big batches.
My FlexUG4 just arrived and I am seeing exactly the same behaviour and errors as above trying to read and program it with my PM3 Easy.
Do you have a Flipper or anything else to read it with?
If you do try and take the foil lube packet off, be super carefull, it’s glued on like crazy and easy to rip open the packaging. I sent mine back today, according to USPS tracking, they should get it Friday. Not sure how long it’ll take for them to do testing and re-sterilization so I can get mine back.
Alignment is key. You don’t want it in the center of the HF part. It should be alone the edge where the antenna traces are.
Thanks all for the prompt replies and help. I had the alignment correct but was receiving “BCC0 incorrect” and “card select failed” errors still. Giving it some pressure and pushing the PM3 down a little against the chip has it reading and configuring as expected now. I’m off to go book in the install. Thanks again!
I’m having the exact same issues with mine but unfortunately mine is already in the skin and it worked great for a little while
Huh, wonder if there’s a problem with these, or if we’re the only 3 unlucky ones.
Anyone with a new UG4, have you tried using an RSP with it? Does it help?
Anyone with a new UG4 or one still in the pack have access to a NanoVNA?
Pressing onto the antenna i feel may be reshaping the field allowing it to read better, i doubt it is bad solder joints and i am wondering if there is a batch of chips that had the capacetence change.
Also note the Proxmark antenna is not amazing. and does benefit greatly from an RSP or one of @XEMON circular antenna’s
When the foil packet was still connected to the bag, the only way I could get any read at all was with the Flipper and a small MFGC.
After the foil packet was off, I could get a read with Flipper and chameleonultra but it still had to be touching. Tried a MFGC with the PM3 but didn’t get a read at all, that’s when I was thinking I had a problem with my generic PM3.
I do have a NanoVNA packed in my box of ham stuff, but already shipped my FlexUG4 back for re-sterilization.
I wonder the same. I am about to pull the trigger on flexug4 and 2 more apexes, but this topic makes me concerned. Anyone here with flexug4 already installed to share experience?
For me, 50% of the reason for getting it is increased range VS a glassie (my xMagic works great, but sometimes needs several seconds to get a read). 25% because it doesn’t need a scalpel to install, and 25% because it can cover all the MIFARE’s etc (don’t need to be able to clone any of that yet that my xMagic can’t cover, but going for future-proofing)
Kind of defeats the purpose if I still end up having to mash my hand against the reader to try and get it to work.
When we use the word “performance” in relation to transponders, we are referring to an intricate dance between many factors to make the overall experience of placing the transponder up to a reader as easy as possible.
This dance involves many partners including antenna performance for both transponder and reader, power requirements of the transponder, power transfer efficiency between the antennas, inductance, impedance, capacitance, resonance, the physics of magnetic field shapes, and a little bit of black magic thrown in for good measure.
The ultimate Gen 4 magic chips consume a bit more power then standard Gen 1 or Gen 2 chips do. The small antenna size of the flex series makes achieving the required power transfer a bit more difficult.
I have noticed though that the Proxmark3 Easy HF antenna is just not great at picking up most flex designs. I think this has to do with that magnetic field shape issue, more than raw power output or anything like that. There are also some oddities in the antenna design which twist the magnetic field up a bit in some key places;
Typically only one via is needed to cross over the spiral loop coil on a PCB to bring both ends of the coil to the oscillator, but for whatever reason they make the coil traces here do looptyloops not once but twice… it’s like forming a twist-knot pastry with the magnetic field, and this will fuck shit up with small antennas trying to magnetically couple with that mess. Larger transponder antennas will do ok with it because they have plenty of inductor spread across a larger area… and smaller x-series can avoid the mess by straddling just one small straight section of the coil path… but flex antennas are right in the shit zone.
The best place I have found for flex on the PM3 Easy is basically right over the serial number on the sticker on the back. Not the barcode, the serial number itself.
Having not looked specifically at placement, best guess is that’s about the only spot I was able to read it with my PM3, but also had to push down slightly on it. Of the 4 things I tried reading it with, the PM3 was the worst by far.
Assuming once you guys get it and test it and re-sterilize, just gimme a “Yeah, it’ll probably work fine” and I’ll be okay with that answer
Just a quick comparison between my flexNT which has a very efficient antenna design and a very low power transponder chip attached, and the flexUG4 on an ACR1252U.
I would say the flexUG4 gets about 2mm to 3mm less range than my flexNT on the ACR1252U.
Okay, that comparison is super helpful actually, thanks. Didn’t know the FlexUG4 needed more oomph to work properly VS the other Flex’s, but that makes sense.
I’ll allow @Satur9 to explain further, but in laymans terms, when he designs the antenna, He allows for invivo difference in tuning.
Ie. When its in the pack it will be
??14.3MHz ?? but once it is installed, it should be closer to 13.56MHz which is obviously where your readers are tuned to…
And the APEX
Processing takes power and time