Proxmark3 easy and chip orientation

Support
1

Hello!

Just got one chip implanted in each hand (Next and Spark2), and I’m playing around with a Proxmark 3 easy I just got too.

There’s something odd with the antennas - I wonder if it’s just me?

The chips only work when they are perpendicular to the Proxmark antennas

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I can confirm that if I wiggle the chip in my hand to have it kinda perpendicular I can read it with the Proxmark. Parallel doesn’t work at all.

On the other readers it seems to work fine with the chips parallel.

Is it the same for everybody?

Thanks!

2

Lay it flat, and go perpendicular across the antenna

But yea, this is well known and pretty much what you have to do with these chips routinely

3

Physics, yo

4

Thanks for the reply!
I was very focused on aiming for the center of the antenna, but as it turns out the best spot for the HF antenna seems to be here:

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and for the LF:
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5

Yeah buddy, The Middle board is redundant and misleading.

Here is Amals PM3 Easy with the middle board removed.

image

6

Can the middle board just be removed entirely? Or are there other modifications one would have to do as well

7

image

Nope

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8

Yes, you will need a 1.5mm hex driver to remove the 8 screws (six on the top, two on the bottom) and a small pair of pliers helps to remove the six standoffs. You will leave the four screws on the back below the LF antenna and the lower four standoffs below the LF antenna. Then you will put the LF antenna back with the three arrows on each side pointing to the middle of the board.

No, but I am tempted to get a second “LF board” made up and mount a hand wired ferrite coil on it as an alternative option, or make a full length clear “board” for protection of the Proxmark3 with a LF antenna coil off the bottom.

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9

Appreciate it! I ended up doing it slightly differently because of screw sizes. I’ll probably make a thread on it later with pictures and whatnot

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10

I found that 2 of the original screws needed to be shortened, I used a Dremel tool.

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11

I think I just used the four from the HF end to hold the LF antenna board on. No shortening and they worked. I can’t guarantee that ours were made in the same place though, so manufacturer differences?

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My Proxmark3 Easy propped at an angle on its middle board.

12

Or perhaps at different times? I did find it rather odd that only two of the six screws I pulled out were short.

13

I removed 8 screws, six from the front and two from the back. Four went back in.

14

That’s how it was for me as well. The short screws were from the HF side. Since the LF side uses 2 standoffs instead of 1, the screws can be longer. On the HF side, you’re putting 2 screws in a single standoff, so one of them has to be shorter in order to have enough room for both.

What I ended up doing is just using both standoffs on the LF side and not bothering with a screw on the top. That keeps everything tight and secure, and gives the LF antenna some protection if I were to drop the PM3 or something.

Image for reference

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15

I still wonder if it’s possible to install the lf coil directly on the bottom of the main board

16

It should be as it would connect to the same connection points… I think.

17

Right, but I’m talking sans screws… essentially soldering the coil to the post hole connections from underside

Essentially I see absolutely smallest form factor as a fun goal

At that point being only 1 card think with some bulgy spots it could probably fit in a wallet

18

No, redesign it so that the HF is on the back of the board, then put the LF coil on the front where the HF currently is, now all of the sticky out bits are on one side. Then encapsulate the front in resin like the chameleon tiny, and Bob’s your uncle.

Sure it would need a lot more work, but you could sell it as the Proxmark3 Easy Slim. :laughing:

19

I ended up putting the middle board back on today while playing around with stuff and discovered that I get approximately a 5V difference from HW Tune between the two formats. The middle board (presumably due to the separation) increases the LF Voltage by roughly 5 volts.

1 Like
20

Did that result in any functional difference or improvement?