Software defined radio

[corksil]

Does anyone have experience with this? In an ongoing attempt to figure out how to program cheap "cloning" 433mhz RF remotes from china, I've purchased an antenna/sniffer.

It can pick up radio frequency across a wide range of of the spectrum and interfaces with computer via USB.

I'm new to this so I don't know the lingo and the proper terms to describe exactly what is does and how it works. Might need some help once it arrives and I get it configured.

[alex.s]

its probably just a usb dvb capture card. you can tune into basically any signal. but complex signals can be spread spectrum or something else which make it more complex than simply tuning into a single frequency. you can watch and see some of the transmitters use interesting rotating frequencies. pretty interesting to just look around at the different stuff that's transmitting in the area. i dont really get what you're trying to do with it? you want to figure out what kind of signal a remote sends and make your own transmitter? are you trying to steal cars or something?

[Triple Jim]

My guess is he wants to operate an electric gate actuator he built.

[Alex]

Originally Posted by alex.s

you can watch and see some of the transmitters use interesting rotating frequencies. pretty interesting to just look around at the different stuff that's transmitting in the area.

That's why I never leave home without one of these.

[alex.s]

I heard the foil actually amplifies the mind control

[corksil]

Yeah it's hard to describe exactly what it is that I'm trying to do. Some RF transmitters use a rolling code chip on the board (HCS3XX) and the frequency actually jumps around every time a transmission is made. Most RF remotes are not rolling code so they are more simple.

Tricky to describe exactly what I need this thing for but I'll try. I ordered a large quantity of chinese RF stuff lately and the instructions are non-existent. Pretty sure I also received different components from different "batches" during the R&D process (if there even is such a thing as R&D with the chinese electronics..)

In simple terms, I'm trying to decode something.

In literal terms, I'm trying to wirelessly sniff the frequency/signal that is being transmitted/received between various RF electrical components. Reason being -- I have no idea how to decipher the various sequences of blinking lights to figure out the pairing/unpairing, and programming/different functions etc.

[corksil]

BTW does anyone know what frequency a typical TV remote works on? I'm assuming it's 315/433mhz or something else common.

With that question in mind... how come you can't turn on any TV with any remote? I'm assuming that the transmission is all the same frequency, but there is a different signal from one TV to the next. Thinking about this further makes me wonder how a single TV remote can operate all functions of the TV.

I'm assuming each remote/TV has it's own niche frequency (433.177mhz for example) -- and each different button on the remote has a different signal (transmission pulsating at different speed of oscillation/Hz).

It's really all just a learning experience.