Mobile RFI kits work two ways: They suppress RFI from on board computers and other sensing/control devices in your vehicle that may cause your radio to be a VICTIM of RFI, and second they suppress RFI generated by your radio as a SOURCE which may affect your on board computers or other devices. Mobile operations of HF radios (1-30 Mhz) tend to experience more RFI effects than VHF/UHF mobile stations. If you have both HF and VHF installations in your vehicles, you may need both kits.
To address separate solutions we have developed two separate RFI kits: one for HF (1.8-300 MHz) mobile installations and another for VHF/UHF (30-1000 MHz) mobile installations. Each kit uses the appropriate ferrite mix for the frequency range desired.