I am sure that for many of you, like for me quite recently, what was happening on the radio was real magic. We turn on the TV or radio, pick up the phone cell phone, we determine our position on the map using GPS or GLONASS satellites - and all this works automatically. Thanks to RTL-SDR we now have affordable way look inside all this magic.

As already mentioned, RTL-SDR is a whole family of cheap TV tuners that can perform the function of an SDR receiver. These toys have different names and brands, but they have one thing in common - they are all built on the RTL2832 chipset. This is a chip containing two 8-bit ADCs with a sampling rate of up to 3.2 MHz (however, above 2.8 MHz there may be data loss), and a USB interface for communication with a computer. This chip receives I and Q streams at its input, which must be received by another chip.

R820T and E4000 are the two most convenient chips for SDR, implementing the RF part of SDR: an antenna amplifier, a tunable filter and a quadrature demodulator with a frequency synthesizer. The figure shows a block diagram of the E4000.

The difference between the two is that the E4000 operates in the ~52-2200 MHz range and has slightly greater sensitivity below 160 MHz. Due to the fact that the E4000 manufacturer went bankrupt and the chip was discontinued, the remaining tuners are becoming increasingly difficult to buy, and their prices are rising.

The R820T operates in the range of 24–1766 MHz, but the tuning range of the internal filters makes it very difficult for the R820T to operate above 1200 MHz (making it impossible, for example, to receive GPS). On this moment Tuners based on this chip are easy to buy and cost about $10-$11.

Tuners based on FC0012/FC0013/FC2580 chips are also sold - they have very serious limitations on operating frequencies, and it is better not to buy them. You can find out what chip the tuner is made from in the product description or by asking the seller. If there is no information on the chips used, it is better to buy elsewhere.

Purchase

IN retail stores they cannot be found, so aliexpress.com will help us. We write R820T or E4000 in the search, sort by the number of orders, carefully read the description (it should clearly say that the tuner uses RTL2832 + E4000 or RTL2832 + R820T chips), and you can order. They are usually sent by Russian Post within 3-6 weeks.

The tuner will also come with a tiny antenna - it is, of course, better to replace it. Good results can be obtained using a conventional MV-UHF “horn” indoor television antenna. In the product description you also need to pay attention to the antenna connector - and either look for a tuner with a regular TV connector, or take out your soldering iron and make an adapter / resolder the connector. It's very easy to kill your device with static electricity when soldering, so be sure to ground yourself.

On many tuners, there are no protective diodes near the antenna connector (in this case U7) - you can either solder them yourself (one to ground, one from ground - I, for example, soldered 1N4148), or leave them as they are and not touch the antenna with your bare hands and protect in every possible way from static electricity.

Software and API for working with RTL2832

rtl_sdr

Rtl_sdr is a driver that provides “inappropriate” use of data from TV tuners based on rtl2832. On Windows, you will have to change the default tuner driver to WinUSB using the Zadig program.

Rtlsdr.dll is required by all SDR programs, and often this DLL is already included in software that uses RTL2832.

Rtl_sdr can also be used through the console utility to test the tuner or merge a piece of air into a file:

Rtl_sdr -f 1575520000 -g 34 -s 2048000 out.dat

During further processing, you need to remember that in the file the bytes of I- and Q-streams appear alternately.

SDRSharp

What to listen to on the radio?

Radio communications in unlicensed bands

Civilian radios, which do not require registration in Russia, operate on frequencies of 433 and 446 MHz. However, in Moscow it is difficult to hear Russian speech there. They can be heard immediately and without problems in SDRSharp, NFM modulation.

Since there are many channels, the plugin for SDRSharp AutoTuner Plugin is very useful - it automatically turns on the frequency on which the transmission is carried out, and thus you can listen to all the radio channels at once.

To listen to walkie-talkies at a frequency of 27 MHz, you need a tuner with an R820T chip or an external converter in the case of the E4000 (for example, the previously described Ham It Up v1.2). The optimal antenna for 27 MHz already requires a more serious one, ~2.59 or ~1.23 m long.

Police radio communications

Police in Moscow and many other regions of Russia have switched to using digital radios operating in the APCO-25 (P25) standard. In P25 the data is transferred to digital form with compression and error correction codes - this allows you to increase the range of stable communication and cram more channels into the same radio frequency band. There is also the option of encrypting conversations, but regular police work without encryption.

A DSD decoder can be used to receive P25 radios. DSD expects audio data as input. You can redirect audio from SDRSharp to DSD using Virtual Audio Cable. DSD is very critical of the SDRSharp settings - I recommend setting the AF Gain to about 20–40%, and perhaps disabling the Filter Audio checkbox. If everything goes according to plan, decoded packets will run in the DSD window, and conversations will be heard in the headphones. This circuit also works with the mentioned AutoTuner plugin in SDRSharp.

I suggest that readers find the frequencies on their own, since this information is not open.

Radio communications between aircraft and dispatchers

For historical reasons, amplitude modulation is used for aviation radio communications. Generally, transmissions from aircraft are easier to hear than from controllers or weather reporters on the ground. Frequency range - 117–130 MHz.

Reception of signals from automatic transmitters of ADS-B aircraft

ADS-B is used to provide both the controller and the pilot with visibility into the air situation. Each aircraft regularly transmits flight parameters on a frequency of 1090 MHz: flight name, altitude, speed, azimuth, current coordinates (not always transmitted).

We can also accept this data in order to personally observe the flights. Two popular ADS-B decoders for RTL2832 are ADSB# and RTL1090. I used ADSB#. Before starting, it is advisable to tune to 1090 MHz in SDRSharp, see if there is a signal and what the frequency error is due to the inaccuracy of the crystal oscillator. This error must be compensated in the Front-end settings: Frequency correction (ppm). It must be remembered that the magnitude of this error may change with the temperature of the receiver. The found correction must be indicated in the ADSB### window (after closing SDRSharp).

The optimal monopole antenna for 1090 MHz is only 6.9 cm long. Since the signal is very weak, it is very desirable to have a dipole antenna installed vertically with the same length of elements.

ADSB# decodes packets and waits for network connections from the client displaying the air situation. We will use adsbSCOPE as such a client.

After launching adsbSCOPE, you need to open the menu item Other -> Network -> Network setup, click on the adsb# button below, make sure that the server address is 127.0.0.1. Then you need to find your location on the map and execute the command Navigation -> Set Receiver Location. Then start connecting to ADSB#: Other -> Network -> RAW-data client active.

If everything is done correctly, then within a few minutes you will be able to see information about the planes (if, of course, they are flying near you). In my case, with a monopole antenna, it was possible to receive signals from aircraft at a distance of approximately 25 km. The result can be improved by taking a higher quality antenna (dipole or more complex), adding an additional amplifier at the input (preferably GaAs), using a tuner based on the R820T (at this frequency it has higher sensitivity compared to the E4000).

Reception of long and short wave analogue and digital radio stations

Before the advent of the Internet, HF radio stations were one of the ways to find out news from the other side of the globe - short waves, reflected from the ionosphere, can be received far beyond the horizon. A large number of HF radio stations still exist today; they can be searched in the range of ~8–15 MHz. At night in Moscow I was able to hear radio stations from France, Italy, Germany, Bulgaria, Great Britain and China.

Further development - digital DRM radio stations: transmitted on short waves compressed sound with error correction + Additional Information. You can listen to them using a decoder. The frequency range for search is from 0 to 15 MHz. It must be remembered that for such low frequencies a larger antenna may be needed.

In addition, you can hear radio amateur transmissions at frequencies of 1810–2000 kHz, 3500–3800 kHz, 7000–7200 kHz, 144–146 MHz, 430–440 MHz and others.

Doomsday Radio - UVB-76

UVB-76 is located in western Russia, has been transmitting on the 4.625 MHz frequency since the early 1980s, and has an unclear military purpose. From time to time, coded voice messages are transmitted over the air. I managed to receive it using an RTL2832 with a converter and a 25-meter antenna lowered from the balcony.

GPS

One of the most unusual features is the reception of navigation signals from GPS satellites to the TV tuner. To do this, you will need an active GPS antenna (with an amplifier). You need to connect the antenna to the tuner through a capacitor, and before the capacitor (on the side of the active antenna) - a 3 V battery to power the amplifier in the antenna.

Next, you can either process the leaked broadcast dump with a matlab script - this may be interesting for studying the principles of GPS operation - or use GNSS-SDR, which implements decoding of GPS signals in real time.

It would be difficult to receive a signal from GLONASS satellites in a similar way - different satellites there transmit to different frequencies, and all frequencies do not fit into the RTL2832 band.

Other applications and limits

The RTL2832 can be used for debugging radio transmitters, eavesdropping on baby monitors and analogue radiotelephones, analyzing communication protocols in radio-controlled toys, radio bells, car remote controls, weather stations, systems for remote collection of information from sensors, and electric meters. With the converter you can read the code from the simplest 125 kHz RFID tags. Signals can be recorded for days, analyzed and then re-broadcast on transmission equipment. If necessary, the tuner can be connected to an Android device, Raspberry Pi or other compact computer to organize autonomous data collection from the radio air.

You can take photographs from weather satellites and listen to broadcasts from the ISS - but this will require special antennas and amplifiers. Photos are decoded by the WXtoImg program.

It is possible to capture encrypted data transmitted by GSM phones (airprobe project) if frequency-hopping is disabled on the network.

The possibilities of SDR based on RTL2832 are still not limitless: it does not reach Wi-Fi and Bluetooth in frequency, and even if you make a converter, due to the fact that the captured frequency band cannot be wider than ~2.8 MHz, it is impossible will accept even one Wi-Fi channel. Bluetooth changes its operating frequency 1600 times per second in the range of 2400–2483 MHz, and it will be impossible to keep up with it. For the same reason, full reception of analogue television is impossible (it requires a received band of 8 MHz; with 2.8 MHz you can only get a black and white picture without sound). For such applications, more serious SDR receivers are needed: HackRF, bladeRF, USRP1 and others.

Nevertheless, everyone now has the opportunity to explore both analog and digital radio broadcasts, touch satellites and airplanes!

In this article I will talk about how, by spending very little money and a little time, you can get a radio receiver capable of receiving anything in the 60-1700 MHz range (radio stations, TV audio, amateur radio, pocket radios and much more). For this
We use a DVB tuner on an RTL2832 chip, operating in a special mode, which can be purchased for $20 or even less.

Radio waves

People use radio waves for a variety of purposes. Radio amateurs communicate with each other, the dispatch service gives instructions to airplane pilots, taxi drivers take orders that they learn about on the radio, the car alarm key fob talks to the car to confirm its authenticity and open the doors. Therefore, listening to the broadcast has always been interesting to many.

TV tuner RTL2832

Now anyone can get acquainted with SDR technology. We owe this to Realtek, which released the RTL2832 chip. Its original purpose is a USB DVB-T decoder for receiving digital TV channels. The analog part (tuning to the TV channel frequency) is implemented by the Elonics E4000 solid-state tuner, for which the RTL2832 has outputs to control it. Thus, based on these two chips and a small number of other parts, manufacturers can assemble USB DVB-T tuners.

This chip was discovered to have a mode that disables all built-in decoding functions and puts it into fast ADC mode, digitizing everything the E4000 outputs at up to 3 million eight-bit samples per second. In turn, the E4000 can be tuned to a frequency from 60 to 1700 MHz, outputting a selected “piece” of the radio range 3 MHz wide for digitization to the RTL2832 input. Adding to this a processing program on a PC, we get a completely working SDR receiver.

How does it all work

I'll try to describe it in simple words:

• An antenna connected to the tuner receives signals from the air.
• The E4000 chip allocates a section of the radio range, starting where we indicated it and with a width of 3 MHz, and amplifies it.
• The RTL2832 chip digitizes this area and transmits it via USB to the computer.
• The program (GnuRadio, HDSDR or another) “tunes” to the selected frequency within the previously selected 3 MHz, performs demodulation in the specified manner and sends the resulting sound to the sound card. It can also send commands to the E4000 chip to switch to another part of the range.

Buy a tuner

We can't do without a TV tuner based on RTL2832.
There is a list of devices that suit us.
The easiest and cheapest way is to buy a tuner on eBay. Finding it is easy - just use the name of the chips as a query. There is not much difference between specific models There are no tuners, you can choose the cheapest one or in the body you like.

Install and configure

Let's look at setting up the software for Windows.

What's next?

Liked? Then the process of improvement is almost endless. There are a large number of much more sensitive and functional SDR set-top boxes. Some of them provide a digitization and review bandwidth of up to 100 MHz, some can work for transmission, almost all more expensive set-top boxes digitize the signal with a resolution of 16 or 24 bits instead of 8. Pay attention to the project

Hello forum users! I decided to create my first topic on this forum.
I’ll tell you how to spend time and some money with interest and get a universal radio receiver in the range of 50-900 MHz. I got it under $20, maybe it’s cheaper now. Last year I bought a USB TV tuner on ebay, the seller no longer sells it, but you can find it in a search for the Realtek rtl2832 Elonics e4000 chip.
This is a Chinese USB TV tuner.

Ask? This is a TV tuner how to make a radio.
There is no need to solder anything. I'll tell you
Download a patched driver with a radio function. convenient proven option - SDR https://public-xrp.s...ase-rev427T.zip With auto tuner function.

For it to work as a radio receiver, we don’t need native drivers, we replace them with the necessary patched ones.
Download the program to replace the firewood and drag it into the downloaded patch (open both and drag it)
Run Zadig.exe, click Options->List all devices, select Builk-in, Interface 0, select the replacement driver - “WinUSB”, click Reinstall Driver

Replaced? Go ahead.
And we launch our patch, downloaded SDR file, open the Release folder-> click SDRSharp.exe, the application will open, click Other and the RTL-SDR/RTL2832U drop-down menu

Where to point.

Did you manage? Click the long-awaited Play, if everything is done correctly it should work.
Now you can drag the scale left or right, or drive it into the field on the top left.
My kit comes with a half-meter antenna.
It catches better with a home antenna. Horn systems. On some, the protective diode is forgotten, so as not to kill the receiver, we don’t touch the antenna with our hands.

Does the zombie box show? Whistle DVB-T format. in my area DVB-T2. So I won’t say anything about TV.
What can you hear taxi drivers, radio amateurs, builders, communication between aircraft and dispatchers, FM radio.
Especially for smart people I tried to briefly describe the process. It's been chewed up on Habrahabr!
Your true noob
Kendi Bober

Don't forget Google knows everything

Long gone are the days when radio scanner was the preserve of the elite, now even schoolchildren can play it!

Many probably remember the 90s or 2000s, when serious devices like AOR or ICOM cost about a thousand dollars and most of us could only dream of buying such a radio scanner. But time does not stand still and now thanks to USB DVB-T TV tuner SDR on a chip RTL2832U + R820T (RTL2832U + R820T2) and special software can be used to make wideband SDR a radio receiver for just $10.
What is a radio scanner? Radio scanner- this is a special broadband receiver with which you can listen to service walkie-talkies and radio stations, that is, you can receive frequencies: traffic police, police, air, railway, Ministry of Emergency Situations, maritime, radio amateurs, private security companies, taxis, etc.

Now, to listen to the above services, it is enough to have Personal Computer with Windows OS and $10 for the purchase of a Chinese TV tuner (FM+DAB USB DVB-T RTL2832U+R820T). You can buy this device on Aliexpress, the link leads directly to the tuner we need, which, by the way, is used in.

Contents: USB tuner, antenna with cable, remote control, disk

The Internet is full of articles on this topic SDR receiver 24MHZ-1850MHz (RTL2832U+R820T), but they are all from 2013 or 2015 with broken links. I personally spent a little over an hour figuring out the device, so I decided to write my own article with up-to-date links to drivers and necessary software.

Description of work

The DVB-T TV USB tuner has the ability to operate in SDR mode. All that needs to be done is to replace the original driver with specialized software. Such a tuner is capable of providing radio reception of all radio stations operating in the frequency range from 24 MHz to 2.2 GHz, including CB radio stations, amateur radio bands 10 m, 2 m and 70 cm, air band, LPD walkie-talkies, taxi drivers, GSM spectrums and others with AM, FM, WFM, NFM, CW, SSB modulations. To operate such a radio receiver you do not need a separate sound card, just insert it into the connector Computer USB or tablet, install the drivers, launch the receiving program and enjoy the reception. The viewing band is 3.2 MHz, i.e. you see all stations in that band at the same time. Frequency adjustment using the mouse wheel. The kit includes a 70cm antenna.

Specifications:

• Frequency range: 24 - 1750 MHz
• Modulation: AM, FM, NFM, LSB, USB, CW (ADS-B, D-STAR, AIS and other types...)
• Span: varies from 250kHz to 3MHz
• Sensitivity: 0.22mKv (at 438MHz in NFM mode)
• Receiver input impedance: 50ohm
• Range filters: external only
• ADC capacity: 8bit
• Dynamic range: 50dB (in CW mode)
• Received signal delay: 340ms.
• Interface: USB 2.0
• PC requirements: any modern
• Operating system: Windows, Linux, Android

Installation and connection

First connect the antenna to the TV tuner - then connect it to USB, there is a danger of static. The CD that comes with the tuner is not needed. Other drivers and programs are required here, which are described below:
Download the drivers (Download - a program to replace the standard tuner driver, universal driver). They are different for Windows XP and for Windows 7.8. Take only those you need, below is a description on English language. For example, zadig_v2.0.1.160.7z

Connect the tuner to usb port computer. To exclude automatic search drivers, it is recommended to disconnect from the Internet for a while (at the time of replacing drivers). Windows will start looking for drivers, don't pay attention to it. Unzip the zadig_v2.0.1.160.7z archive to any folder and run the zadig.exe file. A window will open, menu Options - List all devices, then select our tuner from the list RTL2838UHIDIR and install the Install Driver. We agree with the warning about unverified drivers. After installing the drivers, be sure to restart your computer.

Now let's install a program to control the RTL SRD receiver.
Download latest version SDR (SDR# rev 1430 & ADSBSpy at the time of writing). SDRSharp does not require installation. Download the archive sdrsharp-x86.zip. Unpack them into the sdrsharp folder. Run install-rtlsdr.bat inside the extracted folder. This will launch a command prompt which will download SDRSharp and all the files it needs to run SDRSharp With RTL-SDR. Upon completion of the operation, command line will close automatically. The installation can now be considered complete. Run the sdrsharp.exe file to configure the program.

Beginning of work. Fast start

Let's launch SDRSharp.exe

First you need to configure SDRSharp to work with RTL tuner. Select the device " in the line next to the button RTL-SDR/USB".

- in this stock yours RTL device and tuner chip.

- (RTL Sampling Rate) Receiver bandwidth, 2048 MSPS is 2.048 MHz. The band can be changed from 0.25 MHz to 3.2 MHz. The larger the bandwidth, the greater the load on the processor. Not every computer can work normally with the maximum bandwidth. To start, set it to 1024 for single-core processors and 2048 for multi-core processors. Then experimentally determine the maximum for your system.

- RTL device operating mode. Quadrature reception mode is required for operation. It is installed by default. There are also modes for digitizing the I channel or Q channel. These are specific modes and under normal conditions there is no need for them.

- This is a useful option for owners of the E4000 tuner. Switches the operating mode of the RTL input from zero frequency to intermediate non-zero. Checking this box allows you to completely get rid of the stick in the middle of the screen. For 820 tuners, this option is indifferent and is ignored in the driver code.

- Automatic adjustment gain in the “Tuner mixer - RTL2832 ADC” section. Check this box the first time you run it.

- Automatic gain control in the section "Receiver input - LNA - Mixer". This AGC does not work very well, a lot depends on the antenna, reception conditions and the range you are receiving. It's better to leave this checkbox disabled for now.

- Manual tuner gain adjustment. Allows you to independently change the gain of the tuner input path when the . For the first start, set this regulator to 25 - 36 dB.

In the future, in practice, you will figure out which settings will give you the optimal result; for the first time, these will be suitable in most cases.

- Correction of the frequency of the tuner reference oscillator. Do not change the setting in this field yet. Next we will look at this parameter in more detail.

The program is now configured to work with your receiver. You can press the button .

Tune in to an FM broadcast station. In the Radio tab, enable the modulation type WFM.

Check the box Correct IQ in the Radio tab. This will improve the suppression of the specular channel and remove the stick in the center of the spectrum.

Check the box Filter Audio in the Audio tab. The sound will become more pleasant, high-frequency noise and crackling will disappear.

Adjust the slider Range in the FFT Display tab. RTL dynamic range is low. A spectrum analyzer minimum of -70 dB is sufficient.

Jackdaw Snap to Grid It's better to remove it for now. First you need to calibrate the receiver frequency.

If the sound is choppy, you may have selected the receiver bandwidth too wide and your processor can't handle it.

Click the button and try different settings A.G.C. And RF Gain.

In this video shown installation And setting broadband SDR receiver (radio scanner):

I have long read about the use of USB TV tuners on RTL2832U + R820T chips as an SDR receiver.

The topic interested me, but in the standard version the range was limited to 24 - 1750 MHz. There were articles (,) about refining and expanding the range and capturing the entire HF, but all this was so-and-so “soplestroy”. And then a completed device appeared on Ebay, which was purchased.

I always wanted to have a review receiver. There is equipment, as they say, “for all ranges,” but it’s always useful to see what’s going on within a 3 MHz radius in real time, which is exactly what it was purchased for.

Characteristics:

In a high-quality metal case, motherboard with 2 SMA connectors. One UV from 24 – 1750 MHz, the second HF from 100 kHz – 24 MHz. In the center motherboard still the same TV tuner with modifications.

1. TV tuner board based on RTL2832U + R820T chips.
2. Connection of antenna input 24 – 1750 MHz.
3. HF receiver filters 100 kHz - 24 MHz.
4. Finalization, connection to the 4th and 5th leg of the microcircuit of the receiving part 100 kHz - 24 MHz.

Driver installation for Windows

The description will be for Windows 10, but I think it will work on Windows 7/8.

When an SDR receiver based on RTL2832U + R820T is connected to a computer, Windows installs drivers that are not suitable for our purposes, and the Zadig program (http://zadig.akeo.ie) will help us install the correct drivers.

We connect the SDR receiver to USB, download the Zadig program (http://zadig.akeo.ie) and run it from administrator rights.

Perform the following steps below:

Installing RTL-SDR Drivers: Step 1
Installing RTL-SDR Drivers: Step 2

Installing RTL-SDR Drivers: Step 3
Installing RTL-SDR Drivers: Step 4

Installing RTL-SDR Drivers: Step 5

Windows SDR Software Package (SDRSharp)

SDRSharp software is called "Windows SDR Software Package" on the developer's website.

The software is not installed, but downloaded to a folder, which makes it easy to transfer it to different computers saving all the settings, which was very convenient when I went to the village, where I tested the HF receiver.

1. We select the signal source, in our case the SDR is connected via USB;
2. We enter the connection parameters settings;
3. Select an RTL-SDR receiver;
4. Turn on the AGC (Automatic Gain Control) parameters;
5. And click “Start”.

If the error “Cannot access RTL device” appears while connecting to the SDR

then run the file "install-rtlsdr.bat" from the sdrsharp archive.

SDR connection parameters

Sample Rate	(RTL Sampling Rate) Receiver bandwidth, 2048 MSPS is 2.048 MHz (default). The band can be changed from 0.25 MHz to 3.2 MHz. The larger the bandwidth, the greater the load on the processor. Not every computer can work normally with the maximum bandwidth. If your computer slows down, choose a lower band.
Sampling Mode	RTL device operating mode. The “Quadrature sampling” mode is required for operation.
Offset Tuning	This option is only relevant for the E4000 tuner. Switches the operating mode of the RTL input from zero frequency to intermediate non-zero. Enabling this option allows you to get rid of the “stick in the middle of the screen”. On 820 tuners this option is ignored.
RTL AGC	Automatic gain control in the “Tuner mixer - RTL2832 ADC” section.
Tuner AGC	Automatic gain control in the section “Receiver input - LNA - Mixer”. This AGC may not work very well, a lot depends on the antenna, reception conditions and the range you are receiving. I always turn it on. If you do not enable it, the sensitivity of the SDR receiver will be very low.
RF Gain	Manual tuner gain adjustment. Allows you to independently change the gain of the tuner input path when “Tuner AGC” is disabled.
Frequency correction PPM	Correction of the tuner reference oscillator frequency. Receiving frequency calibration is necessary to accurately match the received frequency indication to its actual value. Description of the calibration procedure: http://rtl-sdr.ru/page/kalibrovka-chastoty-priema

Video review of using SDRSharp

Plugins for SDRSharp

For SDRSharp there are various software modules (plugins) that expand its functionality.

Example plugins:

• DSD Interface plugin (setting description: http://dmyt.ru/forum/viewtopic.php?t=1098)
• And other plugins: http://rtl-sdr.ru/category/plugin

Mobile client SDR Touch

Using the SDR Touch program for Android, you can connect the RTL-SDR to a smartphone or tablet. The receiver is connected with via USB cable and OTG adapter or via the network via IP address to the SDR server.

SDR server

SDRSharp connection to SDR server