Distill:FM Barebones - Broadcast FM Bandstop Filter is a high-quality, high-performance bandstop filter designed for software defined radio (SDR) applications.

Broadcast FM can be particularly problematic due to the high-powered transmitters used for broadcasting in some areas. These signals can overload the front end of an SDR, causing imaging and a number of other issues.

We designed Distill:FM to provide sufficient attenuation for broadcast FM frequencies (>40dB typical) while ensuring adjacent bands, such as the important VHF airband (108-137MHz) are minimally affected. The -3dB rolloff of the filter is 80MHz and 115MHz. Minimal out-of-band insertion loss means the filter can stay in place for most any application. As a true bandstop filter, you are able to pass-through DC (bias power) when it is required.

DC current handling is 250mA (min), and the maximum recommended signal level is +18dBm (5Vp-p), so there is no issue using the filter for higher-power applications.

Distill:FM has its filter circuitry fully shielded with an EMI frame, and has its front end protected by an ESD diode meant for RF applications.

2 mounting holes are available on the PCB for various mounting options, and the SMA hardware (washer and nut) is included.

Documents: