Gain = 15 #Every type of device has different gain settings Sample of rtl-airband config for RTL-SDR device. The solution was to change the central frequency. We have tried to change the bandwidth and gain but it did not help. It may happen that a strong source near you may leak into your recording (even if it is on a different frequency). The problem is called ghosting (thanks to ). We had strong harmonic distortion in the audio signal. However we found a problem with recording the Tower (note: our setup is very close to the airport so we have a strong signal). We limited the bandwidth of RTL-SDR and put the center frequency the same as the frequency of the Tower ( 134.55MHz). We set the bandwidth of RSP1A to 5MHz which gave us 14-bit sampling precision (better audio quality). RSP1A covered the group of channels around 123MHz and RTL-SDR took care of the Tower on 134MHz. Finally, our solution was to use SDRplay RSP1A and RTL-SDR (on two separated antennas). We analyzed the traffic on the channels and found out that the Radar on 127MHz is a “copy” of Radar on 120MHz. We would need about 16MHz bandwidth to cover them all. One of the Radars and the Tower are the problematic ones as they are away from the rest. Sample_rate = 9.00 #bandwidth in MHz around centerfreqįilename_template = "BRNO_Tower_119_600MHz" Gain = "IFGR=20,RFGR=2" #Every type of device has different gain settings Sample of rtl-airband config for SDRplay RSP1A device would look like the following: country = "Czech Republic" ĭevice_string="driver=sdrplay,serial=xxxxxxxxxxxxxx" The “bandwidth” of the SDR - sampling frequency - was chosen wider than needed to overcome possible distortions on the edges. We placed the central frequency in the middle. The green boxes indicate 25kHz bandwidth of one channel. See our configuration in the following figure: So to fully cover the LKTB, we need a pair of RTL-SDRs or one RSP1A. You can notice that the distance between LKTB_TWR and LKTB_APP is 7.75MHz which is much larger than 2.5MHz supported by the RTL-SDR but smaller than 10.6MHz supported by the SDR RSP1A (see previous blog post regarding more technical information). We checked available on-line resources and found main frequencies used in LKTB. If some frequencies are too distant, you may use two SDR devices (we are also using this setup). First, you need to identify VHF frequencies you want to record and decide what is your central frequency and bandwidth. You need to do several steps to set up the SDR. You should end up with a Linux distribution with installed SDR drivers and RTL-airband software running ( ). Please follow the instructions at website. We will aim at software installation and SDR settings. Welcome to the next blog post from our series of “How to set up an ATC voice recorder”. Blog 3: What is the best SDR hardware choice for ATC.Blog 2: Where to place your antenna for ATC recordings.Blog 1: Basic terminology and hardware setup description for ATC listening.For this reason there is no service guarantee - and there is no guarantee that any particular channel will be up 24/7, though we make our best effort to do so and have a good track record of uptime. Available airports can change due to reasons beyond our control. Note that we do not have coverage in the U.K., Belgium, Germany, Iceland, Italy, New Zealand, Spain and other countries where streaming ATC communications is prohibited by law.Īvailable airports/channels are subject to change at any time - LiveATC owns and operates many of the receivers used in the network but many are provided by volunteers. Please check to see if your country, city and/or airports of interest are covered by LiveATC *BEFORE PURCHASING* - check at. The LiveATC network (is the world's largest network of streaming audio feeds focused solely on aviation-related communications, currently covering over 1,200 airports around the world with almost 3,000 different audio feeds and growing daily! Once you find an interesting channel you just add it to your Favorites list for quick and easy access! You can also use the Nearby function to find airports near you. state, Canadian province, or by country to find an airport of interest. LiveATC Air Radio lets you easily browse by U.S. LiveATC Air Radio provides a quick and easy way to listen in on live conversations between pilots and air traffic controllers near many airports around the world. Stuck in the airport terminal and want to know why you're delayed? Live near an airport or enjoy plane-spotting and want to tune in to the pilots and the control tower? Have you always wondered what pilots talk to air traffic controllers about? Now you can stop wondering and tune in live! This notice relates to countries not covered by the system PLEASE READ ***IMPORTANT NOTICE*** BELOW **BEFORE** PURCHASING
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