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Showing posts from February, 2014

Bought a server.

Today was an interesting day. At the end of the day I purchased a server. It is called PRIMERGY RX220 and it is made by Fujitsu-Siemens. It has two Opteron 265’s at 1.8 GHz and 1 GB of ram. It is not the fastest server in the world in fact it is quite old it is 8 years old. But for my intensions I think it is powerful enough. The only thing that bothers me is that it supports max only 500 GB hard drives. I haven’t checked any bios updates, so maybe they have updated it. Hopefully it runs Windows Server 2012 R2 well enough because I got a free key from Dreamspark. If it doesn’t run well I probably install Ubuntu server or something lightweight like that. The main idea right now is to run it as webserver for this website – I think. I know that Elion’s update speed is like 1 Mbps but it beats my current hosting. If my dual wan thingy works maybe even maybe 2 Mbps but that is a stretch. Also idea - run it as file server.
It hasn’t arrived yet via mail, so I don’t even know if it works, so…

Raspberry Pi FM trasmitter

So I was browsing reddit and came across THIS.
It was so cool, I had to try this out. So I took my Raspberry Pi and hooked it up. When it booted up I was able to run the following commands over SSH.

mkdir radio
cd raadio
wget http://omattos.com/pifm.tar.gz
tar –xvf pifm.tar.gz

And that’s it. Now you need to connect a wire to Pi’s 4 GPIO pin. I just connected a random wire. For maximum performance use 20cm wire or dedicated antenna.
To test it out I typed:
sudo ./pifm sound.wav 100
Tuned my radio to 100 MHz and tadaa – Star Wars theme was rolling in.
When the file ends or you cancel it, it stops but the modulation stays on. To get rid of it you need to restart your Pi or run this script I made.
stop For example save it as "stop.py". And run it.
sudo python stop.py
And it should stop.
As you can see the 100 stands for the frequency. For more flags read THIS. Now it even supports stereo.
You can replace the "sound.wav" with other music file. PiFm currently only supports 16 bit 22050…

Reading data from 433Mhz temperature probes.

As the title stated, I had a idea to capture data from those magical things! These thing wirelessly send data between the sensor and the station.





I had one of these probes laying around and I thought I should at least try to capture something from it. I did not have the base station only the probe.

Sounds cool on paper! The first thing I tried to do was actually capture a sample.  I booted into my Ubuntu and launched Gqrx. With my SDR I was able to tune into the 433 MHz region. Those probes usually work around that frequency.

So I captured this around 433.900Mhz AM

This is what that region looks like:



So then I started searching and I found this: https://github.com/merbanan/rtl_433

Went to my linux machine and typed into the terminal (the readme commands did not work for me) :http://pastebin.com/embed_iframe.php?i=0YQ8jDjg

So when that was done I figured how to use that thing.

Everything is super simple when that part is done. So I was able to run this:

rtl_433 –a  - this outputs all it's …