Using a passive antenna (VE3DO loop) with a Clifton Labs Z10042 11 dB Norton amplifier connected directly to Red Pitaya at N6TV, strong intermodulation from two nearby FM broadcast stations on 92.3 and 106.5 MHz was clearly visible (106.5 - 92.3 = 14.2 MHz):
Inserting the 14:1 transformer between the pre-amp and the Red Pitaya reduced the intermod significantly, and atmospheric band noise (wideband sensitivity) improved by about 4 dB:
Red Pitaya is a hardware board with a size slightly larger than a credit card, designed to be used as a measurement and control instrument. It can be accessed through ethernet, and it is devised to be used with a web browser as interface. For the capture and generation of signals, both high and low speed ADCs and DACs are included, which allow its interaction with the environment in lots of applications, with SMA-F standard connectors.