HF Impedance Transformer Kits

Noise Filters - AC/DC

Store / Noise Filters - AC/DC

Our noise filters are designed to suppress common mode noise on AC/DC power lines, Switching Mode Power Supply (SMPS) input/output, and computer/instrumentation power input/output/control lines. Also suitable for PLC control line noise suppression (use mix 77/75 ferrite filters).

Refine by
3136934589 - HF Impedance Transformer Kits
25-AMP (Peak) IN-LINE ELECTRONIC FILTER for 12 VOLTS DC, AUTOMOTIVE, RV RFI, ALTERNATOR, PULSE NOISE SUPPRESSION
25-AMP (Peak) IN-LINE ELECTRONIC FILTER for 12 VOLTS DC, AUTOMOTIVE, RV RFI, ALTERNATOR, PULSE NOISE SUPPRESSION
SKU RFI-N700
$49.95
3136886908 - HF Impedance Transformer Kits
30-AMP (PEAK) IN-LINE TOROIDAL DC NOISE FILTER for 12 VOLTS, ALTERNATOR, PULSE NOISE SUPPRESSION
30-AMP (PEAK) IN-LINE TOROIDAL DC NOISE FILTER for 12 VOLTS, ALTERNATOR, PULSE NOISE SUPPRESSION
SKU RFI-N25
$34.95
982808144 - HF Impedance Transformer Kits
AC Cable Noise Filter for Large Plugs - 3" ID
AC Cable Noise Filter for Large Plugs - 3" ID
SKU ACCF-3
$39.95
2654217922 - HF Impedance Transformer Kits
AC Cable Noise Filter for Standard 120VAC Plugs - 1.4" ID
AC Cable Noise Filter for Standard 120VAC Plugs - 1.4" ID
SKU ACCF-1.4
$12.95
2908543317 - HF Impedance Transformer Kits
AC Power Cord Choke + Power Cord- 120VAC RFI Range: 1-30 MHz, -28 dB Noise Reduction, 15 Amp
AC Power Cord Choke + Power Cord- 120VAC RFI Range: 1-30 MHz, -28 dB Noise Reduction, 15 Amp
SKU AC-CHOKE-6
$19.95
2654217922 - HF Impedance Transformer Kits
Aquarium AC Filter for Heater, Water/Oxygen Pump RFI
Aquarium AC Filter for Heater, Water/Oxygen Pump RFI
SKU AACF-1.4
$12.95
982840126 - HF Impedance Transformer Kits
Big Clamp On RFI Noise Filter for AC/DC power lines, Coax/Multi-wire cable - 1" ID
Big Clamp On RFI Noise Filter for AC/DC power lines, Coax/Multi-wire cable - 1" ID
SKU BCO31
$19.95
2654143999 - HF Impedance Transformer Kits
DC Cable Noise Filter for 2 Gauge and Smaller Wire - 1.4" ID
DC Cable Noise Filter for 2 Gauge and Smaller Wire - 1.4" ID
SKU DCCF-1.4
$12.95
982840130 - HF Impedance Transformer Kits
DC Cable Noise Filter for Large Gauge Wire - 3" ID
DC Cable Noise Filter for Large Gauge Wire - 3" ID
SKU DCCF-3
$39.95
On Sale
1025194825 - HF Impedance Transformer Kits
DC Voltage Common Mode Noise Filter - Marine, RV, Communications, 600 Volts/30 Amps
DC Voltage Common Mode Noise Filter - Marine, RV, Communications, 600 Volts/30 Amps
SKU RFI-DC-30
List price $109.95
Save 18%
$89.95
1725564654 - HF Impedance Transformer Kits
DC-AC Inverter Common Mode RFI/Noise Filter Kit for DC in and AC Output
DC-AC Inverter Common Mode RFI/Noise Filter Kit for DC in and AC Output
SKU RFI-INVERTER
$34.95
977476514 - HF Impedance Transformer Kits
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz
SKU F240-31-1
$9.99
On Sale
977476519 - HF Impedance Transformer Kits
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz, Bulk Pack of 10
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz, Bulk Pack of 10
SKU F240-31-10
List price $100.00
Save 10%
$89.95
On Sale
977476519 - HF Impedance Transformer Kits
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz, Mini Pack of 3
FT240-3I, ID=1.4", AC/DC/Coax Noise Filter, RFI Range 1-300 MHz, Mini Pack of 3
SKU F240-31-3
List price $34.95
Save 14%
$29.95
977476539 - HF Impedance Transformer Kits
FT240-61, ID=1.4", RFI Range 200-2000 MHz
FT240-61, ID=1.4", RFI Range 200-2000 MHz
SKU F240-61-1
$16.95
977476559 - HF Impedance Transformer Kits
FT240-61, ID=1.4", RFI Range 200-2000 MHz, Bulk Pack of 10
FT240-61, ID=1.4", RFI Range 200-2000 MHz, Bulk Pack of 10
SKU F240-61-10
$149.99
977476628 - HF Impedance Transformer Kits
FT240-75, ID=1.4", AC/DC/Coax Noise Filter, RFI Range .15-10 MHz, 10 Pack
FT240-75, ID=1.4", AC/DC/Coax Noise Filter, RFI Range .15-10 MHz, 10 Pack
SKU F240-75-10
$99.95
3042762954 - HF Impedance Transformer Kits
Power Pole DC Power Cord RFI/Noise Filter - up to 30dB Noise Reduction, 45 Amp Connectors
Power Pole DC Power Cord RFI/Noise Filter - up to 30dB Noise Reduction, 45 Amp Connectors
SKU PPNF-3
$34.95
1187030192 - HF Impedance Transformer Kits
Switch Mode Power Supply (SMPS) Common Mode RFI/Noise Reduction Filter Kit
Switch Mode Power Supply (SMPS) Common Mode RFI/Noise Reduction Filter Kit
SKU RFI-SMPS
$27.95
1008627784 - HF Impedance Transformer Kits
Wall Wart RFI Noise Filter Bulk Pack of 10 Filters
Wall Wart RFI Noise Filter Bulk Pack of 10 Filters
SKU RFI-WW-10
$29.95
982840114 - HF Impedance Transformer Kits
Wall Wart RFI Noise Filter Bulk Pack of 100 filters
Wall Wart RFI Noise Filter Bulk Pack of 100 filters
SKU RFI-WW-100
$199.95
1008627777 - HF Impedance Transformer Kits
Wall Wart RFI Noise Filter Pack (5 filters)
Wall Wart RFI Noise Filter Pack (5 filters)
SKU RFI-WW-5
$16.95
Display prices in: USD
These impedance transformer kits have been designed for the Do-It-Yourself (DIY) enthusiast and Instructor workshops on baluns and ununs for antenna matching and RFI use.

The impedance transformers are classified in ratios of 2:1 (100:50 ohm) to 16:1 (800:50 ohm).  The outputs can be configured as balanced (Balun) or as unbalanced (unun) with respect to the inputs which are considered all unbalanced coax at 50 ohms.  All impedance transformers are designed for 1.8-31 MHz unless otherwise specified.