SDR Receiver 4+

Demodulate and play AM and FM signals received by an RTL-SDR, Airspy HF+ or SDRplay radio. Requires a radio and a host computer which are not provided with SDR Receiver and must be separately installed and configured. Streams data from an rtl_tcp, hfp_tcp or rsp_tcp server application which are free and open source applications. The appropriate server application must be installed on the host computer and configured for the attached radio.

SDR Receiver is a Software Defined Radio (SDR) that processes, demodulates and plays AM, narrowband FM and wideband FM signals. Listen to communications from aircraft (AM), amateur repeaters and VHF handhelds, police and fire, NOAA weather reports (narrowband FM) and commercial broadcasts (wideband FM).

• Easily entered and managed lists of stations simplify station selection.

• Export and import lists of stations in CSV or TSV format.

• Adjustable squelch that works for both AM and FM signals.

• Adjustable LNA gain (for RTL-SDR and SDRplay radios).

• Adjustable audio high pass and low pass filters.

• Selectable IQ Offset eliminates DC errors.

• DC Blocker option reduces spurious errors.

• Signal strength indicator that shows power level in the signal passband.

• Multiple sampling rates to accommodate different network bandwidths.

• Selectable 8-bit or 16-bit sample size streaming from Airspy HF+ and SDRplay radios.

• Option to play audio over AirPlay to a HomePod, HomePod mini or any AirPlay compatible device.

• Stream synchronized audio to multiple AirPlay 2 compatible devices.

• Lock Screen shows controls and streaming station information.

• Custom URLs enable another application on the same device to set the station and start streaming.

• Supports VoiceOver.

SDR Receiver processes signals that are streamed over the network from a host computer (Mac, PC or Raspberry Pi) that is attached by USB bus to an RTL-SDR, Airspy HF+ or SDRplay radio. An rtl_tcp server or equivalent application running on the host computer receives baseband IQ data from the radio and streams the sampled signals over the network to the iPhone or iPad running SDR Receiver.

Requires an RTL-SDR, Airspy HF+ or SDRplay radio and a host computer which are not provided with the application. Support for 192 ksps and 384 ksps Airspy HF+ sampling rates requires Airspy HF+ firmware version R3.0.7 or later, and hfp_tcp version v.1.2.117 or later.