Hi,
I try since few days to copy my RF remote control (see file attached).
Usually I use virtualwire but it does'nt have sniffer mode.
What's the best way to follow?
Thanks in advance
Use a laptop and Audacity, as described here.
thanks for the answer but is it possible to do the same thing on arduino? (like with IRremote)
Yes, but it is MUCH easier with a laptop and Audacity.
Could you please give me the way?
Easy it's not for me 
If you can't follow the instructions in reply #2, you'll never solve it. Reverse engineering is not beginner stuff.
No, there are so many protocols, and many use a different way to start, so the Arduino would not know where the signals starts. Those receivers have auto-gain, wich makes it even harder for the Arduino to distinguish a signal from the noise.
Use a computer with line input (with a voltage divider) as jremington wrote and Audacity. Or you can use SDR to capture the signal.
http://airspy.com/ (It used to be called SDR sharp).
Or http://gqrx.dk/
A usb receiver of 10 to 20 dollars is needed.
Do you know what kind of protocol is used by the key fob ?
If it is for example 2272 / 2262 then RCSwitch can be used to detect the code.
For 2272 / 2262 code, also the Fuzzillogic can be used.
https://bitbucket.org/fuzzillogic/433mhzforarduino/wiki/Home
However, if it has a rolling code, you might never be able to create the same signal with an Arduino.
I tried to make a 433mhz sniffer on Arduino a while ago. I was unsuccessful. I was using input capture, but I was getting nonsensical results that I was never able to sort out.
You can squelch the noise at the cost of sensitivity by modifiying the receiver if you have one of the good ones (the little yellow ones with the SYN470 chip - they won my range test by a significant margin) by adding a several-megaohm resistor. See the datasheet for the SYN470 for details).
The problem is the following: when no signal is received, those receivers output noise pulses that cover an extremely wide range of periods, from microseconds to milliseconds.
If you don't already know what the protocol is, only a human looking at the "big picture" (as produced for example by Audacity) can decide how to distinguish the genuine signal from noise.
Koepel:
Those receivers have auto-gain, wich makes it even harder for the Arduino to distinguish a signal from the noise.
There is no AGC path in any of the receivers I've seen, except for the SYN480R based ones. Just two TRF stages and an OP amp detector/amp.
For sure it's NOT a rolling code. the configuration is with dip switch only.
I tried to receive something with RCSwitch demo example without result.
I tried to send a signal from 2 differents RC and from a transceiver using virualWire.
starjuice:
For sure it's NOT a rolling code. the configuration is with dip switch only.
A rolling code can be configured with a dip switch.
I tried to receive something with RCSwitch demo example without result.
I tried to send a signal from 2 differents RC and from a transceiver using virualWire.
There are trillions of ways to get no result. There are only a tiny handful of ways to get a result.
It's not a rolling code because you can take any remote control copy the dip switch and control my door.
starjuice:
It's not a rolling code because you can take any remote control copy the dip switch and control my door.
Any remote with the same firmware, which may or may not use a rolling code. But rolling code or no rolling code, you haven't even got a code. So worry about that first.
Your approach is like proving that the arrow can fit into the bull's eye on the target. It's great, but you have to actually shoot the arrow.
starjuice, use the receiver, make a voltage divider with 2 resistors, record it with Audacity and show us what it looks. Perhaps one of us recognizes the pulses. You can also use a logic analyzer of course. I think that it even possible to use an Arduino as logic analyzer : GitHub - gillham/logic_analyzer: Implementation of a SUMP compatible logic analyzer for the Arduino, but I think you have to use a Mega 2560, since an Uno will have only 1024 samples.
aarg, it is auto-gain. Every 433MHz receiver I have has auto-gain. The cheap modules use a LM358 for the data output and mostly a circuit like this : http://www.hobbycomponents.com/images/forum/MX-FS-03V.gif
I don't see the auto-gain, but it is there
Koepel:
aarg, it is auto-gain. Every 433MHz receiver I have has auto-gain. The cheap modules use a LM358 for the data output and mostly a circuit like this : http://www.hobbycomponents.com/images/forum/MX-FS-03V.gif
I don't see the auto-gain, but it is there
How do you know that? Q1 and Q2 DC bias is fixed.
I know that because that is what I see at the data output. The receivers would not even work very well without auto-gain. They are not receiving FM modulation, but ASK. The gain is not a real gain, but more an offset I think.
That little schematic does not show the pin numbers for the LM358, so I don't know what is going on there.
Here is another schematic : https://dzrmo.files.wordpress.com/2012/07/rx-schematic.gif
And... I still don't see the auto-gain.
Koepel:
I know that because that is what I see at the data output.
If you're looking at the digital output, it may simply be that the gain is "larger than typically necessary" and one or more stages clip when they hit the power rails. Since it's a digital signal this sort of distortion is of no consequence.
There exist regenerative receiver topologies with AGC schemes, but it's not apparent that this circuit is one of them. That said, regenerative receiver design is a bit of a black art, so it's entirely possible I've missed something.
The cheapest receiver modules are superregenerative, and AGC action is an inherent property of a superregenerative design. From the Wikipedia article (among many others)
The amplitude reached at the end of the quench cycle (linear mode) or the time taken to reach limiting amplitude (log mode) depends on the strength of the received signal from which exponential growth started. A low-pass filter in the audio amplifier filters the quench and RF frequencies from the output, leaving the AM modulation. This provides a crude but very effective automatic gain control (AGC).