PC-FM6-32 FM Radio Capture PCle Card (6 to 32 Channels)

The FM Radcap PCIe is a radio capture card designed for simultaneous recording of multiple radio stations. The frequency of each station is set in software and its audio appears as a standard Windows audio input device. RDS decoding is also supported.

The card uses a high-speed A/D converter to digitise the entire FM band, with up to 32 individual tuners. The Radcap achieves exceptionally low audio distortion through the use of linear phase filtering and mathematically precise FM demodulation and stereo decoding. FM demodulation, stereo decoding and RDS decoding (if enabled) are all performed in FPGA fabric.

The card provides 6 stations as standard but may be expanded to 12, 18, 24 or 32 stations for an additional charge.

Drivers have been fully implemented for Windows and Linux, with RDS being available on both platforms now. A 64-bit WDM driver for Windows 10, Windows Server 2016, 2019 and Windows 11 is supplied as well as software for setting the tuner frequencies and monitoring the received audio. A programming API and DLL for software control and monitoring are also supplied.  The Linux driver is Alsa based and supports Kernels from version 3.8.

The card can be configured to operate in stereo, mono or paired mono (two mono stations combined on a 2-channel audio stream) modes. Multiple cards can be used in a single PC, subject to available CPU bandwidth. The audio de-emphasis may also be set to either 50us or 75us. In Australia, New Zealand and Europe 50us is used, while in the USA and Canada 75us is used.

A Windows utility called FMSpectrum is supplied. This displays the RF spectrum from 85MHz to 111MHz, using data from the card’s front-end 256-point FFT and may be useful in selecting the best location for the antenna or resolving interference problems.