PURPOSE
These kits are designed to choke common mode currents going into or exiting from your amplifier cables.Filters are supplied for the RF In, RF Out, Relay Cable/control lines, and AC power line.Use of the filters often helps cure SWR problems between amp exciter and amp and between amp and antenna tuner or direct to antenna.The AC 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.
USE
Standard kit for amplifiers with single input, single output, relay keying and AC input
Deluxe Kit for amplifiers with dual inputs/outputs, frequency/keying control lines
KIT INCLUDES
|
Filter Type |
Usage |
Standard Kit |
Deluxe kit |
|
F240 Ring (1.4” ID) |
RF Exciter input |
1 |
2 |
|
Snap On (1/2” ID) |
Ethernet, PTT control |
2 |
2 |
|
Snap On (1” ID) |
RF Output |
1 |
2 |
|
Snap On (1” ID) |
120/240 VAC Input |
1 |
1 |
|
Total Filters |
5 |
7 |
INSTALLATION GUIDELINES
Standard Kit - Part# RFI-LA-FLEX-1
RF Input:Ring Filter (1.4” ID) – 5-9 turns of RG-58/8X size through center
RF Output:Snap On Filter (1” ID) – 3 turns of coax cable through center
PTT Relay Cable:Snap On Filter (1/2” ID) – multiple turns through center
Ethernet Cable:Snap On Filter (1/2” ID) – multiple turns through center
AC Power:Snap On Filter (1” ID) – 3 turns of power cord through center
Deluxe Kit - Part# RFI-LA-FLEX-2
RF Input (2)Ring Filter (1.4” ID) – 5-9 turns of RG-58/8X size through center
RF Output: (2)Snap On Filter (1” ID) – 3 turns of coax cable through center
PTT Relay Cable:Snap On Filter (1/2” ID) – multiple turns through center
Ethernet Cable:Snap On Filter (1/2” ID) – multiple turns through center
AC Power:Snap On Filter (1” ID) – 3 turns of power cord through center
Also make sure you connect a good RF ground to the amplifier ground post.
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