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The RadioInstigator: A $150 Signals Intelligence Platform

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Re: The RadioInstigator: A $150 Signals Intelligence Platform

#11

Post by panpanna »

SuperNinjaCat wrote: post #9
amingilani wrote: post #2

Wait, an antenna connected to the GPIO pin on a RaspberryPi for transmissions? Correct me if I'm wrong, but doesn't the Pi output square waves, that would cause harmonics if transmitted?

There was an old RPi project released a while ago (PiRadio I think?) which simply involved attaching a jump lead to GPIO pin 4 which allowed the transmission of FM radio signals. It worked on the principal that the Pi had a stupidly powerful clock and thus could be used as a transmitter. I did a little experiment where I hooked it up to a yagi antenna and asked my dad to set his cars radio to the frequency I set the…

This is how some pirate radio stations worked 2-3 years ago.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#12

Post by VvR-Ox »

drmpeg wrote: post #7
amingilani wrote: post #2

Wait, an antenna connected to the GPIO pin on a RaspberryPi for transmissions? Correct me if I'm wrong, but doesn't the Pi output square waves, that would cause harmonics if transmitted?

With low cost transmit capable SDR's now available, nobody should be transmitting trash from a GPIO pin. https://www.digikey.com/product-detail/en/analog-devices-inc...

Yes they should just because they can, it's easier, you don't need extra hardware when an RPi is already there and it's good to know how to do that when no SDR is around.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#13

Post by SuperNinjaCat »

3xblah wrote: post #10
SuperNinjaCat wrote: post #9

Earlier quoted context omitted.

There was an old RPi project released a while ago (PiRadio I think?) which simply involved attaching a jump lead to GPIO pin 4 which allowed the transmission of FM radio signals. It worked on the principal that the Pi had a stupidly powerful clock and thus could be used as a transmitter. I did a little experiment where I hooked it up to a yagi antenna and asked my dad to set his cars radio to the frequency I set the…

"There was an old RPi project..." Is this it? http://icrobotics.co.uk/wiki/index.php/Turning_the_Raspberry...

That link looks very familiar but I remember getting the idea from this article first:

https://makezine.com/projects/raspberry-pirate-radio/

Using this disk image for the RPi:

http://cdn.makezine.com/make/pifm/PiRadio.zip

(good times)

EDIT: That link was definitely part of what I was researching at the time (as it is linked in the project article I posted and I remember reading about the limitations regarding stereo output, as well as the line "Most radio receivers want a signal to be an odd multiple of 0.1 MHz to work properly").

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#14

Post by cinquemb »

VvR-Ox wrote: post #12
drmpeg wrote: post #7

Earlier quoted context omitted.

With low cost transmit capable SDR's now available, nobody should be transmitting trash from a GPIO pin. https://www.digikey.com/product-detail/en/analog-devices-inc...

Yes they should just because they can, it's easier, you don't need extra hardware when an RPi is already there and it's good to know how to do that when no SDR is around.

Yeah, from the creators comment on hackaday:

"But The higher the $$$, the harder it is for people to build one. That’s another allure why I like $150. It’s attainable, and many people already have some parts."

It's this kind of pragmatism that's going to make these affordable tools proliferate and constantly pour cold water over the tech companies Privacy-In-Can™ products and services.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#15

Post by SuperNinjaCat »

panpanna wrote: post #11
SuperNinjaCat wrote: post #9

Earlier quoted context omitted.

There was an old RPi project released a while ago (PiRadio I think?) which simply involved attaching a jump lead to GPIO pin 4 which allowed the transmission of FM radio signals. It worked on the principal that the Pi had a stupidly powerful clock and thus could be used as a transmitter. I did a little experiment where I hooked it up to a yagi antenna and asked my dad to set his cars radio to the frequency I set the…

This is how some pirate radio stations worked 2-3 years ago.

For dramatic effect...during the experiment I actually did make a windows text-to-voice recording saying something along the lines of "you are listening to pirate radio" between the stoner metal songs I had lined up (I was listening to lots of QOTSA at the time to be honest).

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#16

Post by jcims »

cinquemb wrote: post #14
VvR-Ox wrote: post #12

Earlier quoted context omitted.

Yes they should just because they can, it's easier, you don't need extra hardware when an RPi is already there and it's good to know how to do that when no SDR is around.

Yeah, from the creators comment on hackaday: "But The higher the $$$, the harder it is for people to build one. That’s another allure why I like $150. It’s attainable, and many people already have some parts." It's this kind of pragmatism that's going to make these affordable tools proliferate and constantly pour cold water over the tech companies Privacy-In-Can™ products and services.

It's not RF snobbery, the point is that this approach to transmitting RF signal is shitting all over the spectrum with harmonics and potentially interfering with other legitimate activity.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#17

Post by bsder »

VvR-Ox wrote: post #12
drmpeg wrote: post #7

Earlier quoted context omitted.

With low cost transmit capable SDR's now available, nobody should be transmitting trash from a GPIO pin. https://www.digikey.com/product-detail/en/analog-devices-inc...

Yes they should just because they can, it's easier, you don't need extra hardware when an RPi is already there and it's good to know how to do that when no SDR is around.

Except that it is quite illegal and people should be made aware of that.

We already have problems like USB 3 ports causing harmonics in WiFi bands.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#18

Post by cinquemb »

jcims wrote: post #16
cinquemb wrote: post #14

Earlier quoted context omitted.

Yeah, from the creators comment on hackaday: "But The higher the $$$, the harder it is for people to build one. That’s another allure why I like $150. It’s attainable, and many people already have some parts." It's this kind of pragmatism that's going to make these affordable tools proliferate and constantly pour cold water over the tech companies Privacy-In-Can™ products and services.

It's not RF snobbery, the point is that this approach to transmitting RF signal is shitting all over the spectrum with harmonics and potentially interfering with other legitimate activity.

Yeah, a completely insurmountable problem at hand there that totally ruins any utility anyone could get from something like this…

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#19

Post by jdietrich »

cinquemb wrote: post #14
VvR-Ox wrote: post #12

Earlier quoted context omitted.

Yes they should just because they can, it's easier, you don't need extra hardware when an RPi is already there and it's good to know how to do that when no SDR is around.

Yeah, from the creators comment on hackaday: "But The higher the $$$, the harder it is for people to build one. That’s another allure why I like $150. It’s attainable, and many people already have some parts." It's this kind of pragmatism that's going to make these affordable tools proliferate and constantly pour cold water over the tech companies Privacy-In-Can™ products and services.

You can buy an SDR that'll output reasonably clean RF for about $150 - an Adalm Pluto, a LimeSDR Mini or a HackRF One clone.

The barrier to entry to radio has never been lower, which is very much a mixed bag. A lot of people are doing really stupid, really illegal stuff with cheap radio hardware. Quite aside from the legalities, it's just bad manners to splatter all over the RF spectrum. Listen to the bands, get yourself an amateur license, learn to build a lowpass filter, then press the transmit button.

Re: The RadioInstigator: A $150 Signals Intelligence Platform

#20

Post by cinquemb »

jdietrich wrote: post #19
cinquemb wrote: post #14

Earlier quoted context omitted.

Yeah, from the creators comment on hackaday: "But The higher the $$$, the harder it is for people to build one. That’s another allure why I like $150. It’s attainable, and many people already have some parts." It's this kind of pragmatism that's going to make these affordable tools proliferate and constantly pour cold water over the tech companies Privacy-In-Can™ products and services.

You can buy an SDR that'll output reasonably clean RF for about $150 - an Adalm Pluto, a LimeSDR Mini or a HackRF One clone. The barrier to entry to radio has never been lower, which is very much a mixed bag. A lot of people are doing really stupid, really illegal stuff with cheap radio hardware. Quite aside from the legalities, it's just bad manners to splatter all over the RF spectrum. Listen to the bands, get your…

>The barrier to entry to radio has never been lower, which is very much a mixed bag. A lot of people are doing really stupid, really illegal stuff with cheap radio hardware. Quite aside from the legalities, it's just bad manners to splatter all over the RF spectrum.

I get this, but despite it all, I'm going to be more interested at the end of the day, in principle, in solutions that would involve low cost antenna design/filtration techniques/etc, that make the cheap stuff better compared to the buy one component that's 2x amount of an entire system kind of solutions.

Because the reality is that this genie isn't going to go back into the bottle, legalities aside or not.

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