(*****) NFC antenna amplifier/Resonance Circuit V1

NFC antenna amplifier/Resonance Circuit project

Made by @Hamspiced

This is merely my review; full details on the actual project can be found here

INTRODUCTION

WHAT IS THIS?
Tuned circular 13.56MHz HF Antenna to a LC Tank Circuit

WHAT DOES THAT MEAN?
Add this to your reader, and you should see increased read ranges

WHAT DOES IT NOT DO?
Low Frequency 125kHz

TESTING INCLUDING READ RANGES
Some interesting results
For this I used my Phone ( Samsung S21+ ) PM3 Easy, PM3 RDV4 and a Flipper Zero

I considered testing with a PM3 Easy and RDV4, but decided I would focus on more portable readers for now.
I may do PM3s later

Gah, Whatever, I did these too…

PHONE :iphone:

Phone Without
xSeries ( xMagic ) Contact
Flex ( FlexM1 ) 5mm
Card ( Mifare Classic ) 20mm

Phone With
xSeries ( xMagic ) 5mm
Flex ( FlexM1 ) 10-15mm
Card ( Mifare Classic ) 30

FLIPPER :flipperzero_white:

Flipper Without
xSeries ( xMagic ) 5mm
Flex ( FlexM1 ) 15mm
Card ( Mifare Classic ) 30mm

Flipper With
xSeries ( xMagic ) 15mm
Flex ( FlexM1 ) 25mm
Card ( Mifare Classic ) 15mm (interestingly degraded range)

PROXMARK3 EASY & RDV4 :pm3_easy: :pm3_rdv4:

Proxmark3 Without
xSeries ( xMagic ) Contact
Flex ( FlexM1 ) 10mm
Card ( Mifare Classic ) 60mm

Proxmark3 With
xSeries ( xMagic ) 10mm
Flex ( FlexM1 ) 15mm
Card ( Mifare Classic ) 60mm (antenna amp on implant) :no_entry_sign: killed signal (antenna amp on PM3 antenna)

TEARDOWN

image
image

PROs
• Huge improvement on Phone readers

• Good improvement on Flipper zero

• OK improvement on Proxmarks, but mixed results

• Is thin enough to sit inside phone / flipper covers

• These can be used in conjunction with qi wireless charging

• Did I mention how good it is with your phone, Really Good!!!

CONs

:thinking:

• Fragile!?!

• If you get the free option from @hamspiced, you’ll need some antennas, caps, VNA and solder kit

• They are crazy thin which does make the flex pcbs a pain to solder to.

“HACKS”
Possible encapsulation with tape

PRICE
USD$FREE Bare board ( No Cap, No Antenna ) Dangerous Thing community offer only
USD$8.50 Same as above, But on Tindie and not free
USD$50 Tuned working product, bought on Tindie

SUMMARY:

LINKS AND RESOURCES

PCB’s come bare, you will need to supply your own Antenna coil and capacitor

POLL

Rating by the community :robot:

PLEASE ONLY VOTE IF YOU HAVE ONE OR HAVE USED ONE

:star: = :poop:

:star::star: = :pleading_face:

:star::star::star: = :neutral_face:

:star::star::star::star: = :grin:

:star::star::star::star::star: = :trophy:

PRODUCT NAME 1-5 :star:
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0 voters
6 Likes

Good job @Hamspiced . You served most people’s purpose for the resonant repeater stickers with this. I appreciate it.

4 Likes

I still need to finish making v2. I tried on my own but failed bad and had to throw away the entire lot.

Should have more time open up shortly so I can get back in it

2 Likes

Where was the error? The production or Spiced Ham?

@Satur9 is frequently offering his knowledge, and this falls in his wheelhouse, If you have a question, he’s the guy to ask

I reached out, got overwhelmed with work and didn’t follow-up. Failure in my end.

I messed up my circuit in kicad entirely and couldn’t find a proper capacitance given the circuit I made. I think it has to do with the thickness of the traces.

I was going to try to get a working version first then reach out to see the idea he had about doing this without onboard capacitors.

But I made two versions, one for 13.56 and one at 125k for another project I’m working on for Amal. Both runs were trash. Do I’m waiting until I can get some actual dedicated time to look it over and adjust.

PPD is a hard y’all. I hope your wives never have to go through it.

3 Likes

Well I’m around if you want help figuring anything out, and I can even throw in some money for PCB orders if you need.

I’m really sorry to hear that. I hope everything went okay with the birth and it’s just the natural course of the emotional rollercoaster she must be going through. Things are tough anyway right now so she’s justified in any anguish experienced while we’re all already at an emotional high water mark.

2 Likes

sorry for the delay to reply to you.

I think i got it figured out. If this run is successful i may reach out in reducing the footprint. I still havent jumped into altium and i think that is my next move as kicad is a bit too basic.

PPD is just a hell of a disease. i feel pretty safe in calling it that. My baby boy is super healthy. My wife though is just a different person now. its hard. birth is hard on her, breast feeding is hard, marriage is hard…

2 Likes

I just finished my third design from scratch in Altium and I really love it honestly. Very sensible piece of software, and there’s a ton of features you can utilize or not to make your life easier

1 Like

Maybe i am just getting old. Its hard for me to take time to dedicate to learning a whole new software. Ill get in there i just dont know the timeframe.

2 voters currently

Average vote 4.5 Stars

I voted 5 stars

Somebody else obviously voted 4 stars.

I’m not calling anybody out, but I am curious as to the loss of a star :man_shrugging:

@Hamspiced
If you have time would you be able to do the same test as I did with your V1 inside a Flipper case?
I was just surprised with some of the results.
It was probably my placement of the antenna amp.

MY RESULTS

Also, now that you have the V2’s available, and if you have time Would you be able to do a range comparison between them also?

3 Likes

For visibility, I would like to but I’d rather the tests be objective so I’m reaching out to you via DM to send you one to continue your review.

3 Likes