Why dont the jammer work?

Sub-GHz
#1

Hi.

Recently got a flipper as i would love to learn more about security and RF stuff.

Today i found some sub-GHz files for jamming different frequencies. I then tried to jamm my car at 433.92 and it worked! My car would not unlock when i pressed the keyfob. Later i tried to jamm my moms car at the same frequency and it did not work at all. How come? My car is an older car and my moms car is relatively new, would that be the reason? And if so, why?

Or could it be the modulation the jamming files are running? I see the files are running am650, but maybe it need to be on am270?

I am a noob to this stuff, so sorry if anything dont make sense. And i would like to point out that i am not gonna go around jamming random stuff! I do it on stuff i own as a fun way of learning :slight_smile:

#2

Try the frequency analyzer next to the other remote to make sure it is operating on the same frequency, it could be on another frequency like 315/390/868 for example. Then there are modulation types that could change results. So check what could be different on both devices.

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#3

I did check it with the analyzer, it operates on the same frequency 433.92. Will look into the modulation, thanks for your reply!

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#4

Don’t assume it only uses a single frequency. Check the 317mhz range for a second signal.

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#5

Good call! Ill check that out. But wouldn’t that frequency show up in the analyzer automatically? Or do i have to do anything to listen in on other frequencies? Only 433,92 showed up when i tried it.

#6

It can’t scan all frequencies simultaneously. It can only check channels one at a time. A natural reaction is to take your finger off the button as soon as you get a hit if you aren’t looking for multiple frequencies.

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#7

Sorry if this is a dumb question: what button are you talking about? When i run the frequency analyzer on my flipper i dont have to hold any buttons. Frequencies it picking up just pops up in the analyzer.

#8

The car fob doesn’t perpetually transmit.

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#9

Ohh, thanks man! :slight_smile: