PURPOSE These kits are designed to choke common mode currents going into or exiting from your Tuner Genius cables. Filters are supplied for the RF Input (s) RF Outputs, DC power and LAN input. 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. The LAN cable choke keeps any RFI off the LAN cable input. USE RFI-AT-FLEX-TG Standard kit for tuners with SO2R option and RFI-AT-FLEX-TG3 for tuners with 3 antenna outputs option (1X3). Note if you use other cables into the tuner such as PTT or otherwise, use FSB31-1/2 snap on ferrites for these lines and wind 2 or more turns thru center if possible. These ferrites sold separately. KIT INCLUDES Filter Type Usage SO2R Kit 3 Antenna Kit Snap On (1/2” ID) DC Power 1 1 Snap On (1/2” ID) Ethernet/LAN input 1 1 Total Filters 6 6 INSTALLATION GUIDELINES SO2R Kit - Part# RFI-AT-FLEX-TG (2 Inputs, 2 Outputs) RF Output:Snap On Filter (1” ID) – 3 turns (1/2" cable) or 6 turns (1/4" cable) of coax cable through center for each output - Use 1 for channel A and one for channel B Output RF Input Snap On (1" ID) - 3 turns (1/2" cable) or 6 turns (1/4" cable) of coax cable through center for each input - Use one for channel A and one for channel B Input Ethernet Cable:Snap On Filter (1/2” ID) – multiple turns through center DC Power:Snap On Filter (1/2” ID) – 2 or more turns of DC (+ and -) power cord through center 3 Antenna Kit - Part# RFI-AT-FLEX-TG3 (3 Antennas, 1 input) RF Output:Snap On Filter (1” ID) – 3 turns (1/2" cable) or 6 turns (1/4" cable) of coax cable through center for each output RF Input Snap On (1" ID) - 3 turns (1/2" cable) or 6 turns (1/4" cable) of coax cable through center for TX input Ethernet Cable:Snap On Filter (1/2” ID) – multiple turns through center DC Power:Snap On Filter (1/2” ID) – 2 or more turns of DC (+ and -) power cord through center Also make sure you connect a good RF ground to the tuner ground post.
FSB31-1
RF Output
2
3
FSB31-1
RF Input
2
1
$129.95
Iron powder cores are more stable than ferrites and do not saturate as easily so they are best for tuned circuits, filters, and high power inductors. They come in different “Mixes” for use at different frequencies. For best “Q” use the Mix specified for your frequency.To find the number of turns to give the desired inductance for your coil use the formula below:
Turns = 100 x 
Toroid Dimensions
To order specify core size and mix (e.g. T200A-2). Available in sizes that have µH per 100 turns shown in table.
All iron powder cores are special orders. Please allow one week for shipment after order received.
The iron powder cores shown in the above tables are primarily used for either high power feed line chokes for common mode current reduction or for 4:1 and 9;1 very high power transmission line transformers.
For high power feed line chokes, choose the inside diameter of the iron powder core closest to the transmission line outside diameter and use 6-20 cores at the junction with the antenna feed.
For 4:1 (50/200 or 75/300 ohm) transmission line transformers in the range of 1.8-30 Mhz, select the size appropriate for the power level as follows:
T200A x 2 = 1.5KW
T300A x 2 = 2.5KW
T400A x 2 = 5KW
Use Mix 2 for all the above transmission line transformers. Fully assembled and enclosed units are available for each of the power levels. Click HERE for information.
4:1 transmission line transformers using iron powder cores are typically used for ladder line to 50 ohm coax connections
For .1 – 2 Mhz wide band transformers use Mix 26 which has a higher permeability and requires less turns to achieve a given inductance. Mix 2 has almost constant permeability from 1-30 Mhz. Mix 26 has an initial permeability of 75 at .1 Mhz and gradually decreases to about 10 at 30 Mhz. For high power AM broadcast range (.5-1.7 Mhz) transformer, use Mix 26 to reduce the turn count.
Minimum order for iron powder cores is $50
Shipping on larger cores in quantity may be more than $10 – email/call for quote.