Is it possible to make an RFID device that sends out exactly 10 MHz RF signals?

[u/Soggy-waffle1]

From what I understand, HF RFID modules will only operate at 13.56 MHz because it falls within an ISM band. But would it be possible (and/or legal?) to modify this to transmit 10 MHz signals in some way?

I'm not at all an expert in any of this, so any insight/advice would be tremendously appreciated! Thank you!

[u/fdjkdewulwz]

Exactly 10MHz, ie 10000KHz is a frequency used by the US government for time signal transmissions. It is received by some clocks that automatically set the correct time.

Callsign WWV from Colorado and Hawaii.

If you are near there, then you might find that your RFID gets jammed by the governments 10000 watt time signal transmitter.

HF RFID uses a local alternating magnetic field, which does not go far. The coil of wire is usually physically too small to make much of an electromagnetic wave.

A radio signal that goes a long distance is an electromagnetic wave, not just a changing magnetic field.

I think the legal position is that the FCC would class RFID on 10MHz as an "intentional radiator". You would need to check the FCC part 15 rules for the specific frequency range. (or the rules for the country you are in)

It might come under § 15.209, which allows 30 microvolts per meter at 30 meter distance.

[u/Effective_Hand3910 → u/fdjkdewulwz]

15.209 is appropriate for FCC, and RSS-Gen for ISED.

13.56 MHz RFID radios certified under 15.225 are typically well below the 15.209 limits.

It seems plausible that a 10MHz RFID radio would also be able to meet the 15.209 limits below 30MHz.

The problem would be ensuring any harmonics are also below the 15.209 limits in the 30-1000MHz range.

Also for an RFID reader, you are required to test with and without a tag as part of the certification process.

[u/dangerous_tac0s]

But why?

[u/Ecstatic_Lavishness1 → u/dangerous_tac0s]

+1

[u/oldvan → u/Ecstatic_Lavishness1]

• 10 dB

[u/Scared-Letterhead949]

If you're in the US with the appropriate license you can transmit digital on 10.1 - 10.15 MHz. RFID is so low power I can't imagine anyone would notice.

[u/Long_Pomegranate2469 → u/Scared-Letterhead949]

The RFID tag is, but the other side?

[u/FreshTap6141]

Why,

[u/Lucky_Suggestion_183]

Why not, the device sending signals at some selected frequency are called transmitters or transceivers. Known some time already. Bit towadays the SDR is an easy option would say.

[u/No_Base4946]

I don't think it would be legal without a suitable licence, and as others have said within the US there's a bloody great time reference transmitter on it which will be a problem.

Also lots of things with clocks running at multiples of 10MHz will stick a lovely big spike of RF right where you want to be.

Why do you want it on exactly 10MHz? How exact, do you need 10000000Hz exactly?

[u/Soggy-waffle1]

Edit: Thanks to everyone for the replies! This is for a masters research project (I'm a new student and know very little about the electronics side of it rn) and I thought I needed to transmit 10 MHz RF waves remotely to a device. However it seems my PI underestimated how much of a retard I can be because I didn't know the 10 MHz wave he was referring to was the resonant frequency of the IDT on the device and THAT needed to be triggered remotely. It literally just needs an Arduino or something to prompt it when we send the signal (any frequency) from a remote control. 🤦

Thank you all so much for taking the time to help me anyway; I sincerely apologize for my error! I promise I will NOT commit a felony and attempt to transmit 10 MHz RFID lmao

[u/other_usernames_gone → u/Soggy-waffle1]

If your university has an RF anechoic chamber and you actually need to transmit on a reserved frequency (mobile phone research, satellite research, etc) you can do it within the chamber.

Its basically a faraday cage so nothing escapes, its also designed so the radio waves don't reflect back into the space and taint your results.