Zero One Blog Forum Development

Two radios for rolljam

I think it’s entirely reasonable and makes sense in the scope of this device to have two radios (could be another CC1101) so that one can be used as a jammer for rolljam type attacks… I imagine other uses could be found for the extra radio too, basically making the device full duplex, you could be communicating, or recording a signal with the one radio while performing an attack with the other. Is there really not enough room for this?

1 Like

one transceiver is enough. receiver cant receive anything then it jamming.

Isn’t that literally the entire concept of the rolljam attack? Obviously they are operating at slightly deviated frequencies.


The rolljam attack indeed needs to operate a receiver and a transmitter at the same time so a single transceiver can’t be used.
I don’t think they will be adding another CC1101, however you could plug one into the gpio.

1 Like

for this attack (from the image) the receiver need a very thin receive window. this window can be achieved either with help of SDR receiver and huge math or with band-pass filter with high Q.
for all of this paths it needs to have special RF part. Now it will not work.

Usually with one rf transceiver signal receives up to CRC or some known part and then transmitter jams this part.
so one transceiver is enough. for attack from image it will need to build very complex device and it will work unstable because of huge difference between remote’s schematics.

I’d have to find it, but I posted to the forum something about using a GPIO pin like RPiTX does to send a 433 band jamming signal. Squarewaves work great, so if you could set up some sort of timing to jam-listen-jam-listen quickly enough, it may just work.

Yeah, that RPiTX thing looks really neat. I had no idea you could… transmit radio without a radio transmitter (if I’m reading this right). :face_with_raised_eyebrow:

The problem with jamming with square waves is that you will jam much more frequency’s than the one you are trying to jam/transmit on. So there is a good chance you will transmit on reserved/illegal frequency.
It’s also worth noting that you can’t transmit radio with all gpio enabled devises, however I don’t know the details of this.