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Compatibility with Animal chips

Hi there,

It was recommended that I post here after commenting on Kickstarter enquiring if this would support pet microchips which operate at 134kHz.

These are common in Australia along with i believe a lot of countries - basically most if not all pets get a tag implanted, and if that pet is lost/runs away and loses their collar, any vet can ‘scan’ the tag in the pet and see its serial number which links to a database with the owners phone number.

In terms of compatibility, the first question is if the antenna is putting out enough power to couple well with small glass tags - this has two benefits, it would work on pet tags, and also human RFID implants since they are the same form factor.

Normally getting compatibility with both sorts of tag is pretty easy from a hardware standpoint, instead of aiming for your antenna to be tuned to 125kHz, a lot of people aim for 129-130kHz - this is usually close enough to 125 and 134 to work well for either.

This is done for most Proxmark stock antennas with good success. Another idea is that an extra ‘tuning capacitor’ could be added to the receive circuit and switched in software with a transistor, so the coil could be tuned to 125, and it could ‘detune’ to read 134 - but this is often unneeded.

You can also find me on the Dangerous Things forum - where a lot of implants are discussed - If you would like, i can try and organise for some chips to be sent to you to test with your antenna design!

Thanks, let me know if you would like more details!
Compgeek

4 Likes

This is also common in Europe, and I would like to see this feature!
But I think this mod works becouse the proxmark has enough power to overcome the inefficiency from having the antenna frequency not quite matched?
The tuning capacitor seems like it would be a more reliable on low powered hardware but I don’t know how involved this change to the design would be.

I think this is an important feature!

This would be a great feature!

I agree that having a sufficiently powerful RFID hardware setup would be critical to make it work, but you’d need that to couple with the small glass tags anyway regardless of the slight difference in frequency.

And to my understanding, the chip used can pump out plenty of power, check out the HydraNFC.

Normally you’d decrease power in a battery powered device, but since it won’t be constantly reading, and has a user interface to request a scan, i don’t see why it couldnt put out more power on a read to make this work. That said, I’ve never had the hardware in my hands, so this is all speculation until @zhovner or someone on the team can test.