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A subreddit for the low-cost, DIY software defined radio (SDR) community. While originally dedicated just to the rtl-sdr project, relevant legal content related to general SDR, RF and similar projects is also welcomed.
Feel free to ask questions but please check the wiki first.
"rtl-sdr" is a generic term for cheap USB digital TV (DVB-T) receivers that use the Realtek RTL2832U chipset, which can function as general purpose software defined radios (receive only). All rtl-sdr compatible devices employ the RTL2832U as an ADC and USB controller, but different RF tuners may be used. Note that rtl-sdrs do not transmit!
Typical specs (some depend on specific tuner):
- Cost: ~$5-45 USD
- Frequency range : 24 - >1760 MHz (100 KHz - 24 MHz in direct sampling mode)
- Max sample rate: 3.2 MS/s (2.6 MS/s in practice)
- Resolution: 8 bits/sample
- Noise figure: < 4.5 dB
Resources - Please read this first - before posting!
The rtl-sdr project page Source of the rtl-sdr driver software and hub for its continued development. (osmocom.org)
See our wiki with tutorials and other resources including a Quick Start page to verify your dongle works. They all tend to have good quality control, irregardless, or perhaps even inversely proportional to price.
The supplied antenna is nearly worthless and is unsupported here. Here is a great, broadband Planar Disk Antenna that outperforms most commercial antennas of similar size for under $65-75 and can be built in a half hour or less by beginners with less than $10 in parts. Please verify your dongle is working with a good antenna before complaining that you cannot receive something. Just because an antenna "is sold" does not mean its good or even marginal. In contrast, the Planar Disk is almost free and it performs quite well in an indoor setting.
What is an SDR? Free HF "WebSDR" here.