This RFi kit was created to eliminate RFI issues from the excellent Heil Parametric Receive Audio System which can highly tailor audio signal from your radio to a a powered speaker or multiple headphones. However when installed near a high powered HF antenna it can ave RFi issues. This kit was created out of necessity from a ham using high power antennas near the radio. The use of the ferrite filters completely eliminated the RFI issue allowing the ham to enjoy the use of the PRAS.
The ferrite filters are selected to suppress RFI from 1 to 300 MHz. The filters are easy to install, don’t require modification of the protected equipment and work in almost all cases. See product picture for suggested filter use.
What is included in the kit?
The RFI-PRAS kit contains a a ring filter for the AC power cord used on the DC supply cables to the PRAS and high powered speakerr and 3 additional snap-on filters for the both ends of the speaker cable and for the audio input (from the transceiver/audio source) to the PRAS..
You get 1 ring filter and 5 1/2" ID snap on filters and an installation manual.
We specify impedance ratios as an output to input ratio where the output (or load) is given first and the input is given second (e.g. 100:50 (2:1) would mean a 100 ohm output and a 50 ohm input; a 25:50 (1:2) would mean a 25 ohm load and a 50 ohm input). Most all products use a 50 ohm input unless otherwise specified.
We have products that are available as kits for the do-it-yourself (DIY) person or fully assembled and tested units for the “Plug & Play” crowd.
Our impedance transformers are available using two different topologies: Binocular cores or toroid cores with multiple turns for increased effectiveness and wide band frequency transformations. We utilize single and multiple core transformers using high order windings when needed to extend product performance.
We rate the power ratings as watts PEP (Peak Envelop Power) with standard duty cycles for various modes. To determine the PEP rating required for your needs, see: Choke & Transformer Power Ratings
This website page serves as a link page to the frequency ranges of our impedance transformers configured as either baluns or ununs. You can click on a picture to go to the specific page about the products described in the picture.