Proxmark3 community

jaeger2000

Contributor

Registered: 2009-09-10

Posts: 17

Your antenna is unusable.

Hello,

-I am using a 125KHz HID proximity card.
-Executing the command: tune gives the error:
"# Your HF antenna is unusable."
-I read through the antenna section:
http://code.google.com/p/proxmark3/wiki … cy_antenna
-Do I need to install an antenna for the PM3 to work?

Steps:
1.) I received my PM3 board.
     I made the firmware on the PM3 and software on my computer up to date.
2.) I want to determine the type of RFID card I am using?
3.) I run the command: tune
4.) I receive the output:
# LF antenna:  0.00 V @   125.00 kHz
# LF antenna:  0.00 V @   134.00 kHz
# LF optimal:  0.00 V @ 12000.00 kHz
# HF antenna:  0.10 V @    13.56 MHz
# Your LF antenna is unusable.
# Your HF antenna is unusable.
5.) I purchased a low frequency antenna from "proxmark3.com".
I am considering installing the antenna.

XEROEFFECT

Contributor

From: Sydney Australia

Registered: 2009-07-20

Posts: 132

Re: Your antenna is unusable.

Hi Jaeger2000,

Yes- you do need to install the antenna for PM3 to work. Try the tune command again with the low frequency antenna attached to your board. Good luck.

John

Contributor

From: Wales

Registered: 2009-08-21

Posts: 56

Re: Your antenna is unusable.

125Mhz is Low frequency anyway - so you won't need a HF antenna to read your HID tag.

jaeger2000

Contributor

Registered: 2009-09-10

Posts: 17

Re: Your antenna is unusable.

Hello,

Anyone tried this:

I have the Hirose connector as per the diagram in the above wiki link and two terminating wires from
the antenna loop.

1.) What is a cost effective way of attaching one loop end to TP2 and the other to TP5 on the Hirose?
I don't have a soldering iron and its >100$.

2.) I will eventually put the device in a protective casing.  Does the Antenna before and when in the
case need to be insulated/earthed?

djmanning

Member

Registered: 2008-09-22

Posts: 11

Re: Your antenna is unusable.

It's possible to connect the antenna to the hi-rose connector with a wire wrap tool.  You can find a cheap one at Radio Shack:  http://www.radioshack.com/product/index … =107590412

If you've never used a wire wrap tool, here's some help: http://www.me.umn.edu/courses/me2011/ro … /wrap.html

Make sure to scrape off the insulation before wire wrapping.

dj

djrevmoon

Contributor

Registered: 2008-06-23

Posts: 13

Re: Your antenna is unusable.

Hello,

Anyone tried this:

I have the Hirose connector as per the diagram in the above wiki link and two terminating wires from
the antenna loop.

1.) What is a cost effective way of attaching one loop end to TP2 and the other to TP5 on the Hirose?
I don't have a soldering iron and its >100$.

2.) I will eventually put the device in a protective casing.  Does the Antenna before and when in the
case need to be insulated/earthed?

Where do you live that you cant buy or borrow a soldering iron for less than 100$????
Wire wrap is possible but very sucky. Get a cheap soldering iron, 2nd hand should be possible for under 10$ if you're not picky. Darn, you can even get them new for under 10$: http://www.radioshack.com/product/index … Id=2062728

John

Contributor

From: Wales

Registered: 2009-08-21

Posts: 56

Re: Your antenna is unusable.

I bought a solder for £5 in Maplin.

Sure it takes like 5 minutes for it to get hot enough, but it works

I'm pretty sure that the wire-wrap thing wouldn't work. It has the wrong diameter and number of turns (compared to what i'm used to seeing)

To be honest mate, if you're looking for a low frequency antenna - get the one off proxmark3.org.
If you need to make a HF antenna (even though you are using a 125KHz card...) i can't really help you as i've never made one.

I would suggest wrapping the wire first, and then using sellotape to give it some shape/strength. Not too much obviously, but enough to keep it as one big loop.

Then, you could either wrap the antenna wire around the hirose wire, and then secure the connection with more tape (the ghetto way), or you could get a soldering iron from your local electronics store and you're good to go.

Last edited by John (2009-09-17 10:24:47)

jaeger2000

Contributor

Registered: 2009-09-10

Posts: 17

Re: Your antenna is unusable.

Hello,
-My eBay searchers didn't work originally.
      -You can get cheap (<25$ solder irons delivered for 25W) rom eBay.
-I guess the practitioner should be aware that as a rule of thumb:
Solder iron 20-30W  for PC board and I.C.
Solder iron 40-60W  for electric parts.
Solder iron 80-100W  for when large heat capacity is required.
kind regards,
JaEGeR.