Issue with Proxmark 3 Easy LF Antenna not Scanning

So I received my Proxmark 3 Easy today from Dangerous Things and set everything up following the guide here. After getting everything up and running, I found I was able to scan HF cards, but I was unable to get any of the included LF cards to scan. When I start the proxmark software of my computer running Windows 10, the terminal displays this:
Upon running the command hw tune the terminal displays this:
The program says the LF antenna is ok but at the bottom of the picture, you can see the message that says the LF values are all zero.
I then investigated further by using the lf tune command and saw the LF antenna was only show 60mV.
I searched the forum and could not find any topics related to my issue so I decided to create this one. If anyone could provide any insight into how to solve my problem I would greatly appreciate it!

First thing I’d ask - are any of the screws loose, or is the LF antenna on backwards? There should be arrows on the LF antenna post area, and they need to point towards the middle of the PM3 / away from the USB connector.

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Just checked and the antenna is in the correct orientation and I tightened some screws that felt loose, but I still had the same results.

Were you holding it or setting it down on a conductive surface? I remember seeing a video where Amal had similar results when he shorted it out with his hand.

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I have been using it on top of the anti static bag it arrived in and placed the anti static bag on my mouse pad.

I’m not totally sure but I think some of those are conductive, could you please try using it on another surface?

I am at work right now but I will try on another surface when I get home this evening.

So I just tested it placed on wood and had the same results any other suggestions?

using a different cable homeslice

Check all of the screws in the middle of both long sides…

The two screws and the two standoffs need to be tight as the connection for the LF antenna runs from the rear board through the middle to the front board.

Here you can see the triple Chevron and the little arrows on the middle board, plus the entire stack of screws and standoffs that need to be checked.

You should also look at the antenna solder blobs to make sure they look good.

Just tried using 4 different cables and I am still getting the same results.

Just checked the screw tightness and the solder blobs look good but still no luck.

sounds odd… like maybe a dead or shorted antenna loop. what if you take the LF antenna off completely? same result on the hw tune and lf tune?

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Just tested without the LF antenna on and got the same results with hw tune and lf tune.

This may be a dumb answer, but is it possible the cards are not configured correctly? It is also possible that the cards don’t work. They are cheap and often aren’t reliable and good that come with the proxmark.

Not sure if I was any helpful but anything helps right lol…

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That would normally be a good thing to check, but the bogus numbers (1832072.03 V - 0.00 kHz) and “Not showing LF tuning graph since all values is zero” after running

hw tune

indicate a problem with the antenna connection or the antenna itself (or potentially something further along in the LF antenna circuitry).

Yep! Always worth a shot, it can be the weirdest things sometimes (as shown by the frequent USB cable issues with proxmarks).


Can someone more knowledgeable than me tell me if replacing the LF antenna board with something less usable (like a paper clip) would damage the Proxmark3? I wouldn’t expect it to work, but I would be curious if that would change the readings from an lf tune. No antenna is acting the same way as the provided antenna, so would shorting out the antenna be dangerous and would that be expected to show any difference?

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not sure but probably not good to dead short it… LF antennas are long and have resistances associated with that wire length… still, probably wouldn’t burn it out to do that, but long term if you are just leaving it on LF TUNE and walking away with a short like that then it’s probably going to limit the overall life of the RF output driver