Specifications

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Functions as a respectable HF receiver or spectrum analyzer. All demodulation and signal selection is done by
the computer software. Uses USB 1.1 to communicate with a PC. The use of Fourier transform, 190 kHz
continuous click-to-tune spectrum display, gives this device phenomenal capabilities for finding signals and
tailoring the reception bandwidth. Internal buffer holds 262,000 samples. Rf section is wide open from 0 to 30
MHz. For higher frequencies, it would be fed from the 10.7 MHz IF output of a receiver and can display up to 4
MHz of spectrum. Thus, the SDR-14 could be thought of as a low-cost real-time spectrum analyzer. But it's
much cheaper than the offerings from Tektronix, Anritsu and Agilent, which can cost 22 times more than the
SDR-14. Frequency coverage 0-30 MHz
The only specs provided are minimum detectable signal which is around -134 dB from 1.5 to 30 MHz. Because
of the speed limitation imposed by the USB 1.1 interface, the SDR-14 can only demodulate signals when the
bandwidth is set to 190 kHz or less.
Information from the manufacturer
The SDR-14 is a 14-bit software defined radio receiver. It offers a broad range of spectrum analyzer and
demodulation capabilities. The hardware samples the whole 0-30 MHz band using a sampling rate of 66.667
MHz. The digital data from the ADC is processed into I and Q format using a direct digital converter (DDC).
The I and Q data is then sent to the PC for processing using a USB 1.1 interface. All of the demod and spectral
functions are done on the PC side.
For sample rates faster than the USB can support, a memory buffer will store up to 262144 samples at up to
66Msamples/sec and then the SDR-14 will send the buffer at the slower USB rates back to the PC. This allows
large FFT processing to be done on a block of contiguous sampled data at the full A/D sample rate.
Demodulation is not possible since the blocks of data are not continuous.
The SDR-14 does not do any other signal processing except for the complex baseband conversion and
downsampling. Any spectral analysis or demodulation must be done in software by the PC. In other words there
is no digital signal processor in the SDR-14 available for demodulation, FFT's, or other custom processing. It is
merely a sampling and down conversion/down sampling device.
The SDR-14 has 2 inputs. One is a direct input to the A/D for custom applications. The other input has a preamp
and 30MHz antialiasing filter so that the input can be used for measuring/receiving signals from 0 to 30MHz
without external filtering.