iSDR for Iphone and Ipad

iSDR is a software defined radio application compatible with the iPhone®, iPod touch® and iPad™. iSDR is designed for experimenters, shortwave listeners, and amateur radio enthusiasts who would like a truly portable software-defined radio receiver.

Requirements

Compatible with iPhone, iPod touch (2nd Gen.) and later, and iPad. Requires iOS 3.1 or later. Note: iSDR puts high demands on the device processor and works best on iPhone 3Gs, iPod touch 3rd Gen., and iPad devices. Because earlier devices are likely to exhibit significant degradation in visual and audio quality, and may not provide for an external microphone, iSDR is restricted to newer devices only.

Although iSDR will install and launch successfully it is NOT RECOMMENDED for use on iPhone 3G or iPod touch 2nd Gen.

iSDR Explained

Please note: receiving live on-air signals will require purchasing or constructing a “quadrature sampling detector (QSD)” RF front-end device, and connecting it between an antenna and the microphone input jack. Without a QSD RF front-end iSDR will play a pre-recorded I/Q recording of actual radio signals. See the Advanced Use section for more information on RF front-end devices.

iSDR is not a streaming audio application. The iSDR application is designed to let the listener experience actual on-air radio reception of signals snagged from the ether by an honest-to-goodness wire antenna!

iSDR does not require Internet connectivity, a cellular network, Bluetooth, or Wi-Fi. What you will need in order to receive live signals is an external device (known as an “RF front-end”) that converts radio signals into audio signals that can be fed into the iPhone’s microphone input. More information on RF front-end devices is provided below. iSDR’s Offline Mode does not require connecting any external hardware to your iPhone, allowing you to fully experience recorded iSDR signals with absolutely no specialized equipment required!

Features

• Six receive mode settings: USB, LSB, CW, AM, FM* and Binaural.
• Selectable bandwidth settings for each mode.
• Signal strength meter covering 120 dB of dynamic range with peak and average power indication.
• Three AGC settings: fast, slow, and off.
• Three display modes: Spectrum, Waterfall and Oscilloscope.
• Download audio-format spectrum files using iTunes file sharing.
• Most PCM file formats are supported, including .wav and .caf.
• Most file sample rates are supported with automatic resampling to 44.1 kHz bandwidth.
• Embed the center frequency in your file names and iSDR will automatically display the correct frequency!
• Built-in example audio file means the app is always ready to provide an authentic SDR demonstration!
• Tuning, mode, bandwidth and AGC settings are all controlled from within the main display – no menu searching!
• Tune quickly using a single touch to the display screen, or tune precisely using the rainbow tune bar.
• Change radio settings with a simple double-tap action to the red cursor, mode text, AGC indicator or signal grid!
• Up to 44.1 kHz of available spectrum bandwidth.
• Dimmable semi-log or linear spectrum grid (native Settings app only).
• Adjustable CW offset (native Settings app only).
• Monaural microphone input automatically adjusts display to 22 kHz bandwidth.
• Automatically detects if external audio is available for receiving live signals (menu selectable).
• Reverse I/Q stereo input logic (menu selectable).
• User-adjustable displayed center-frequency setting, including negative frequency values (menu selectable).
• Display lock prevents settings from being changed inadvertently.

*FM mode is not supported for monaural signals, and will not appear as a mode selection unless stereo audio (live or recorded) is available. Narrow band FM only: 16 kHz or 11.2 kHz bandwidth.