BUY THIS KIT NOW TO REDUCE NOISE IN THE RECEIVER AND SUPPRESS INTERFERENCE TO/FROM OTHER ELECTRONICS ON YOUR VESSEL.
Works on most marine HF transceivers including ICOM M700, M710, M800, M801, M802, M810, GM800 HF Transceivers up to 60 MHz. Also applicable to SEA 225 & 323, Furuno FS 1502, SGC SG-2000 and similar HF marine radios with external antenna tuners.
Purpose. The RFI kit is designed to be installed on your radio transceiver to reduce Radio Frequency Interference (RFI) caused by common mode current on the outside of the coax braid at the output of your radio and AC/DC power cable and antenna tuner cable.
This kit will help reduce or eliminate:
1. “Hot mic” RFI caused by poor grounding of antennas or common mode currents from linear amps feeding unbalanced (coax fed) antennas without baluns/line isolators.
2. RFI to other electronic devices including audio/video systems, computers, marine electronics, etc.
A side benefit is a reduction in noise floor in your receiver depending on the amount of noise being introduced by common mode currents (which are blocked/reduced by the chokes in this kit).
These chokes use a special mix of ferrite core material that is effective in suppressing radio frequency interference from transmitters and high noise floor on receivers.
The split beads beads are easy to use, don’t require modification of the protected equipment and work in almost all cases, even when plug-in filters fail.
Use of the chokes often helps cure SWR problems between transceiver and antenna tuner s used on marine systems. The DC power line choke helps keep common mode current out of the power line which could cause interference to other devices connected to the same power line if not suppressed.
Included are the following chokes and installation guidelines:
RF Input/Output: Antenna feed line choke installed between radio and antenna tuner coax to reduce noise into receiver and suppress RFI. Includes double barrel male connector for joining choke directly to antenna tuner.
DC Input: 1.4" inside diameter filter ring – coil 3-7 turns of DC power cable through center
Antenna tuner cable: Two 1/2 snap on for 1-2 turns through center at each end of cable.
A simple ferrite ring filter on the DC power line can help suppress the RFI noise affecting the victim device or keep the DC power cord from acting as an antenna and radiating RFI into other victim devices. This kit is also useful on laptop computer supplies, routers, cable modems, wireless phone charges, etc.
Installation is quick and easy: Just wrap the DC power cord through the center of the ring filter as many times as you can and reinstall. For best results with long DC power lines, use one at the ring filter at the wall wart end (to prevent the wall wart power supply from using the DC line as an antenna) and another at the DC plug end (to prevent the electronics in the powered device from using the DC power cord as an antenna). Typical installation is shown below:
The filter suppresses RFI in from .1-100 MHz. Inside diameter is 3/4 inch/19 mm.
Since most households and office environments have multiple wall warts we offer the Wall Wart RFI Filter kit in bulk quantity packages.
Known RFI Generators include Roku/Sling-TV power adapter - Interference heard in the AM broadcast band and harmonics. Also many ethernet Cable/DSL modems, cell phone chargers, computer power adapters have the same issue: using the AC or DC side of the power supply as a radiating antenna. RFI solution is to use a linear power supply, change adapters or wall wart ferrite filters