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DVB-T FM DAB 820T2 RTL2832U RTL SDR Software Defined Radio Scanner USB 2.0

RTL-SDR
RTL-SDR is a very low-cost software defined radio that uses a DVB-T TV tuner dongle based on the RTL2832U chipset. It allows the DVB-T TV tuner to be converted into a wideband software defined radio via a new software driver. Essentially, this means that this TV tuner USB dongle with the RTL2832U chip can be used as a computer based radio scanner. This sort of scanner capability would have cost hundreds or even thousands of dollars just a few years ago. The RTL-SDR is also often referred to as RTL2832U, DVB-T SDR, RTL dongle or the “$20 Software Defined Radio”. There are many other software defined radios better than the RTL-SDR, but they all come at a higher price.

Software Defined Radio
Radio components such as modulators, demodulators and tuners are traditionally implemented in hardware components. The advent of modern computing allows most of these traditionally hardware based components to be implemented into software instead. Hence, the term software defined radio. This enables easy signal processing and thus cheap wide band scanner radios to be produced.

Scanner Applications
The RTL-SDR can be used as a wide band radio scanner. Applications include:
• Listening to unencrypted Police/Ambulance/Fire/EMS conversations.
• Listening to aircraft traffic control conversations.
• Scanning trunking radio conversations.
• Decoding unencrypted digital voice transmissions.
• Decoding POCSAG/FLEX pager traffic.
• Tracking and receiving meteorological agency launched weather balloon data.
• Tracking your own self launched high altitude balloon for payload recovery.
• Receiving wireless temperature sensors and wireless power meter sensors.
• Listening to VHF amateur radio.
• Decoding ham radio APRS packets.
• Watching analogue broadcast TV.
• Sniffing GSM signals.
• Using rtl-sdr on your Android device as a portable radio scanner.
• Receiving GPS signals and decoding them.
• Using rtl-sdr as a spectrum analyzer.
• Receiving NOAA weather satellite images.
• Listening to satellites and the ISS.
• Radio astronomy.
• Monitoring meteor scatter.
• Listening to FM radio, and decoding RDS information.
• Listening to DAB broadcast radio.
• Use rtl-sdr as a panadapter for your traditional hardware radio.
• Use rtl-sdr as a high quality entropy source for random number generation.
• Use rtl-sdr as a noise figure indicator.
• Triangulating the source of a signal.
• Searching for RF noise sources.
• Characterizing RF filters and measuring antenna SWR.

Frequency Range
This is dependent on the particular tuner variant used in the dongle, and the particular implementation. Some dongles, like our RTL-SDR Blog V3 also utilize the direct sampling mode which can enable reception below 28 MHz.

Tuner Frequency range
R820T2 24 – 1766 MHz (Can be improved to ~13 – 1864 MHz with experimental drivers)

Sample Rate
The maximum sample rate is 3.2 MS/s (mega samples per second). However, the RTL-SDR is unstable at this rate and may drop samples. The maximum sample rate that does not drop samples is 2.4 MS/s, however some people have had luck with 2.8MS/s and 3.2 MS/s working well on some USB 3.0 ports.

ADC Resolution
The native resolution is 8 bits, but the Effective Number of Bits (ENOB) is estimated at ~7. Decimation in software may raise this value.

input Impedance
Since this device is for TV, it has an input impedance of about 75 Ohms. However, remember that the mismatch loss when using 50 Ohm cabling on a 75 Ohm input will be very minimal at less than 0.177 dB.

Minimum PC Requirements
Generally, at least a dual core processor of some sort will be required for most general GUI based software defined radio software. Command line tools and ADS-B decoders may work with less powerful hardware. Single board PCs like the Raspberry Pi 3, and Android mobile devices can also run several applications.

Best Performing & Lowest Cost Device
The cheapest, most common and generally best performing dongle at the moment is the R820T2. The R820T/2 is generally regarded as having better performance and sensitivity for most interesting frequencies compared to others. For ADS-B, the R820T is much more sensitive at 1090 MHz. The R820T2 is currently the recommended dongle, unless you need the higher frequencies that other higher cost devices provide and are willing to pay a premium price.

RTL-SDR Blog RTL2832U 1PPM TCXO HF BiasT SMA Software Defined Radio + Antennas
Includes
• 1x RTL-SDR Blog brand R820T2 RTL2832U 1PPM TCXO HF Bias Tee SMA Dongle (V3)
• 1x Dipole antenna base with 60cm RG174
• 2x 23cm to 1m telescopic antenna
• 2x 5cm to 13cm telescopic antenna
• 1x 3m RG174 extension cable
• 1x Flexible tripod mount
• 1x Suction cup mount

Applications

Great for many applications including general radio scanning, air traffic control, public safety radio, ADSB, AIS, ACARS, VDL2, trunked radio, P25/DMR digital voice, TETRA, POCSAG, weather balloons, APRS, NOAA APT or METEOR M2 weather satellites, Outernet, Inmarsat, Iridium, GSM, Milsatcom, radio astronomy, meteor scatter monitoring, DAB, or for use as a low cost panadapter with a traditional ham radio.

Just search our RTL-SDR Blog website (sorry direct links are not allowed on eBay) for your application of interest to see some ideas.

Improvements

This unit has several improvements over generic and other brands including:
• R820T2 tuner
• Improved passive component tolerances
• A 1 PPM temperature compensated oscillator (TCXO)
• HF mode via direct sampling built in (can tune down to 500 kHz unlike basic RTL-SDR's which can only go to 24 MHz)
• SMA F connector
• Aluminium shielded case with thermal pad for passive cooling to improve L-Band performance
• Software activatable 4.5v bias tee circuit
• Improved PCB design for lower noise and less spurs
• A USB noise choke, more bypass capacitors, and built in ferrites for less PC noise
• Improved ESD protection (additional ESD diode and extra ESD discharge paths)
• An improved front end circuit designed for wideband use (other models still use a circuit designed for DVB-T only)
• Several breakout pads on the PCB for advanced users

This is an RTL-SDR software defined radio receiver with RTL2832U ADC chip, R820T2 tuner, 1PPM TCXO, SMA F connector and aluminium case with passive cooling. Tunes from 500 kHz to 1.7 GHz with up to 3.2 MHz of instantaneous bandwidth (2.4 MHz max stable, 3.2 MHz if your application is tolerant to USB drops). (HF works in direct sampling mode - V.3 models and above only). Perfect for use as a computer based radio scanner with free software like SDR#, HDSDR, SDR-Radio, Linrad, GQRX or SDR Touch on Android. Works on Windows, MacOS, Linux, Android and even embedded Linux computers like the Raspberry Pi.

The Dipole antenna kit is perfect for helping beginners get great reception. The short antennas are great for ADS-B, and the longer antennas work well at the lower frequencies. When used in a V-Dipole configuration the antenna is an excellent option for 137 MHz satellites such as NOAA/Meteor M2 weather and the ISS. In the vertical configuration it is great for terrestrial signals. The two mounts allow you to easily mount the antenna outdoors for best reception. Please note that you should not use the antenna permanently outdoors or during bad weather. It is designed for portable temporary outdoor use. For using custom antennas note that this dongle has an SMA F connector (not RP-SMA).

This model has several key improvements over other models. It uses the improved R820T2 tuner, has a 1PPM TCXO (2 PPM initial offset, 1 PPM temperature drift), has improved component tolerances and an SMA F connector. It also comes with a software activatable bias-tee circuit for powering external devices such as LNA's and active antennas. It also has HF reception capabilities. Most standard RTL-SDR dongles can tune down to 24 MHz at the lowest. This model has hardware that unlocks the "direct sampling mode", and allows for tuning down to 500 kHz. There is a built in 25 MHz low pass filter for optimizing this mode.

Various other improvements over other models have also been applied. For example a choke has been added on the USB line and additional bypass capacitors and power line ferrites have been added for reduced internal & PC noise, the PCB has been redesigned for significantly lower noise performance, ESD protection has been improved, the front end circuit has been optimized for wideband use (other models are still optimized for DVB-T frequencies), the LDO has been upgraded, and several break out pads have been added for advanced users.

Requires USB 2.0 (works on most USB 3.0 ports, but we cannot guarantee it to work on all so please ensure your PC has a USB 2.0 port just in case). Installation on Windows is simple, please Google for the RTL-SDR Blog Quickstart guide (links are not allowed on eBay sorry).