RF Baluns Transformers Isolators

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REM-BAL (REMOTE BALUN) Radio Works 1.5kW 4:1 Remote Balun

Price: £59.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 4:1 * 50 Ohms * Freq. 1.8 - 30MHz * Power 1.5kW * Socket SO-239 * Eye bolt fasteners * Size 58 x 203mm
The REM-BAL is is a 4:1 current type balun and is ideal for open wire to coax interfacing, especially external to the operating position. Unlike voltage baluns, current type baluns maintain output balance over a wide range of loads. Can be used with a transmatch.

T-4-PLUS Radio Works 2kW 1:1 Line Isolator

Price: £47.95 (Including VAT) Low Stock - Phone
Quantity:

* Current type * Ratio 1:1 * Impedance 50 Ohms * Bandwidth 1.8 - 30MHz * Power 2kW * Sockets SO-239 * Size 58 x 203mm
The T-4Plus Line Isolator has been designed so that it can easily replace other Line Isolators. The isolation factor is nearly 150% of the original values available in early models, and the leakage path has been practically eliminated.

T-4GPLUS Radio Works 2kW 1:1 Grounded Line Isolator

Price: £51.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 1:1 * Impedance 50 Ohms * Bandwidth 1.8 - 54MHz * Power 2kW * Sockets SO-239 * Grounded version * Size 58 x 203mm
The T-4GPLUS is the grounded version of the T-4. The T-4GPLUS should be installed directly at a properly installed ground rod, or other station ground system. If you are using a vertical antenna, it should be installed right at the feedpoint.

T-4-500 Radio Works 500W 1:1 Line Isolator

Price: £39.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 1:1 * Impedance 50 Ohms * Bandwidth 1.8 - 54MHz * Power 500W HF, 100W 6m * Sockets SO-239 input & output * Size 38 x 122mm * Weight 200g
The T-4-500 Line Isolator compliments the new line of Radio Works current baluns. Built to a high standard, the sockets are in fact silver plated with gold plated centre connection with PTFE insulation. Suitable for amateur and professional applications where up to 500W is used down coaxial lines. Provides excellent isolation while keeping losses to a minimum.

B1-2KPLUS Radio Works 1.5kW 1:1 Balun

Price: £41.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 1:1* Impedance 50 Ohms * Bandwidth 3.5 - 30MHz * Power 1.5kW * Socket SO-239 * Eye bolt fasteners * Size 58 x 203mm
This balun is designed for dipoles, inverted V antennas, and similar 50 Ohm feed designs.

B4-2K Radio Works 1.5kW 4:1 Balun

Price: £49.95 (Including VAT) Good Stock Level
Quantity:

* Voltage type * Ratio 4:1 * 50 Ohms * Freq. 3.5-30MHz * Power 1.5kW * Socket SO-239 * Eye bolt fasteners * Size 88 x 88mm
The B4-2K 4:1 voltage balun is ideal for folded dipoles, delta loops or other medium impedance balance antennas where ATUs are not required.

BU-50 Diamond 50 Ohm Balun

Price: £34.95 (Including VAT) Low Stock - Phone
Quantity:

The BU-50 is a 1:1 50 Ohm HF balun covering 1.7 to 40MHz. It will handle 1.2kW PEP and helps reduce feed line radiation and radiation pattern distortion.

BU-55 Diamond 50 Ohm Balun

Price: £46.95 (Including VAT) Good Stock Level
Quantity:

The BU-50 is a 1:1 50 Ohm HF balun covering 3 to 75MHz. It will handle 500W PEP and helps reduce feed line radiation and radiation pattern distortion. SO-239 socket.

CMF-2000 Common mode filter 1-54MHz 2kW SSB attenuation -50dB max RF choke line isolator

Price: £159.95 (Including VAT) Good Stock Level
Quantity:

CMF-2000 Common mode filter 1-54MHz 2kW SSB attenuation -50dB max RF choke line isolator

CMF-5000 Common mode filter 1-54MHz 5kW SSB attenuation -50dB max RF choke line isolator

Price: £209.95 (Including VAT) Good Stock Level
Quantity:

CMF-5000 Common mode filter 1-54MHz 5kW SSB attenuation -50dB max RF choke line isolator

HB-1-200 HARI Balun 1:1 50 Ohms 200W SSB/CW

Price: £29.95 (Including VAT) Low Stock - Phone
Quantity:

* Balun 1:1 * 50 Ohms * 200W SSB/CW (500W PA DC input) * SO-239 * Weight 200g
Top quality 1:1 balun for use with dipole and trap dipole antennas with feedpoint of 50 Ohms. Power rating 200W, more than enough for 100W rigs.

HB-4-200 HARI Balun 4:1 50 Ohms 200W SSB/CW

Price: £29.95 (Including VAT) Good Stock Level
Quantity:

* Balun 4:1 * 50 Ohms * 200W SSB/CW (500W PA DC input) * SO-239 * Weight 200g
Top quality encapsulated 4:1 balun for use with quad antennas with feedpoint of 200 Ohms. Power rating 200W, more than enough for 100W rigs.

HB-6-200 HARI Balun 6:1 50 Ohms 200W SSB/CW

Price: £29.95 (Including VAT) Good Stock Level
Quantity:

* Balun 6:1 * 50 Ohms * 200W SSB/CW (500W PA DC input) * SO-239 * Weight 200g
Top quality 6:1 balun for use with folded dipole type antennas with feedpoint of 300 Ohms. Power rating 200W, more than enough for 100W rigs.

HB-1-1 HARI Balun 1:1 50 Ohms 1kW SSB/CW

Price: £42.95 (Including VAT) Low Stock - Phone
Quantity:

* Balun 1:1 * 50 Ohms * 1kW SSB/CW (2kW of PA DC input) * SO-239 * Weight 300g
Top quality 1:1 balun for use with dipole and trap dipole antennas with feedpoint of 50 Ohms. Power rating 1kW SSB/CW for use with high power transceivers and linears.

HB-4-1 HARI Balun 4:1 50 Ohms 1kW SSB/CW

Price: £49.95 (Including VAT) Good Stock Level
Quantity:

* Balun 4:1 * 50 Ohms * 1kW (2kW of PA DC input) * SO-239 * Weight 400g
Top quality 4:1 balun for use with dipole and trap dipole antennas with feedpoint of 200 Ohms. Power rating 1kW SSB/CW for use with high power transceivers and linears.

HB-6-1 HARI Balun 6:1 50 Ohms 1kW SSB/CW

Price: £49.95 (Including VAT) Good Stock Level
Quantity:

* Balun 6:1 * 50 Ohms * 1kW (2kW of PA DC input) * SO-239 * Weight 400g
Top quality 6:1 balun for use with folded dipole tyep antennas with feedpoint of 300 Ohms. Power rating 1kW for use with high power transceivers and linears.

HB-1-10 HARI Balun for end fed Beverage antenna

Price: £49.95 (Including VAT) Good Stock Level
Quantity:

* 200W * SSB/CW * 1-30MHz
10:1 Balun 50 / 500 Ohms for end fed Beverage antenna, one end to ground

MFJ-907 Variable RF Transformer 2-50 Ohms 1kW 1.8-30MHz SO-239 connectors

Price: £72.95 (Including VAT) Good Stock Level
Quantity:

Multi-tap variable RF transformer matches low impedance (2-50 Ohms) of mobile antennas (verticals, screwdriver type etc.) to 50 Ohm transceiver. 11 impedance ratios. Use in reverse to transform high impedances to 50 Ohms. Handles 1kW. 1.8 to 30 MHz. SO-239 connectors.

MFJ-911 4:1 Balun 300W

Price: £26.95 (Including VAT) Good Stock Level
Quantity:

True 4:1 current balun/unun. Transmission line transformer using low-permeability ferrite cores gives a relative flat response 1.8 to 30 MHz. Easily handles 300 Watts. Transforms 200 Ohm balanced or unbalanced loads to 50 Ohms. 2-way binding posts provided for hookup.

MFJ-911H Switchable Balun 1:1 or 4:1 300W 1.8-30MHz

Price: £49.95 (Including VAT) Low Stock - Phone
Quantity:

Switchable, true 1:1 or 4:1 current balun/unun. Transmission line transformer using low-permeability ferrite cores gives amazingly flat response 1.8 to 30 MHz. Easily handles 300 Watts. Transforms 200 or 50 Ohm balanced or unbalanced loads to 50 Ohms.

MFJ-912 W9INN Ext Balun

Price: £76.95 (Including VAT) Good Stock Level
Quantity:

* Size 125 x 78 x 55mm * Power rating 2kW * Ratio 4:1
The use of this balun allows you to employ ladder line as the main feed and so take advantage of the very low loss that results. The ladder line is attached to the two large insulators on the balun unit and the output fed via 50 Ohm coax cable to the transceiver. The great advantage of this method of feeding is the extremely low losses that result, even with long lengths of balance line.

MFJ-913 4:1 Current Balun 300W

Price: £32.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 4:1 * 50 Ohms * Freq. 3.5-30MHz * Power 300W * Socket SO-239 * Eye bolt fasteners * Size 45 x 93mm (body only) * Weight 225g
The MFJ-913 4:1 current balun is ideal for folded dipoles, delta loops or other medium impedance balance antennas where ATUs are not required.

MFJ-915 RF Line Isolator 1:1 Current Balun 1.8-30MHz 50 Ohms

Price: £32.95 (Including VAT) Low Stock - Phone
Quantity:

* Current type * Ratio 1:1 * Impedance 50 Ohms * Bandwidth 1.8 - 30MHz * Power 1kW * Sockets SO-239 * Size 48 x 150mm (body only)
The MFJ-915 Line Isolator has been designed to be placed in line with 50 Ohm coaxial cable to reduce or eliminate stray RF. This stray RF can be a major problem with some multi-band dipole type antennas, and can cause burns and other problems with electronic equipment while reducing antenna radiation.

MFJ-917 Current Balun for SWR/Antenna Analysers

Price: £32.95 (Including VAT) Good Stock Level
Quantity:

1:1 Current balun lets you use SWR and Antenna Analyzers on balanced line antennas and other loads. 1.8-30 MHz.

MFJ-918 1:1 Current Balun 1.8-30MHz 50 Ohms

Price: £27.95 (Including VAT) Good Stock Level
Quantity:

MFJ-919 4:1 Current balun 1.5kW

Price: £66.95 (Including VAT) Good Stock Level
Quantity:

* Current type * Ratio 4:1 * 50 Ohms * Freq. 3.5-30MHz * Power 1500W * Socket SO-239 * Eye bolt fasteners * Size Square (body only) * Weight
The MFJ-919 4:1 current balun rated at 1500W is ideal for folded dipoles, delta loops or other medium impedance balance antennas where ATUs are not required.

1:1-BALUN 400 Watts 1.8-30MHz

Price: £33.95 (Including VAT) Good Stock Level
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1:1-BALUN 400 Watts 1.8-30MHz by M0CVO

4:1-BALUN 400 Watts 1.8-30MHz current balun 300 Ohm to 50 Ohm

Price: £33.95 (Including VAT) Good Stock Level
Quantity:

4:1-BALUN 400 Watts 1.8-30MHz current balun 300 Ohm to 50 Ohm

9:1-UNUN 400 Watts 1.8-30MHz unbalanced to unbalanced current transformer

Price: £33.95 (Including VAT) Good Stock Level
Quantity:

9:1-UNUN 400 Watts 1.8-30MHz unbalanced to unbalanced current transformer

1:1-BALUN-1.5 1.5kW 1.8-30MHz Balun

Price: £54.95 (Including VAT) Good Stock Level
Quantity:

1:1-BALUN-1.5 1.5kW 1.8-30MHz Balun by M0CVO

This is a 1:1 balun able to handle up to 1.5KW* RF power. It is used to feed a balanced antenna, such as a centre fed dipole or doublet with an unbalanced feeder, such as coaxial cable. It will reduce static on the feedline, thus reducing unwanted noise and prevent RFI being fed back into the shack.

*Please note, this is for intermittent amateur / ham radio use and not for AM broadcast stations.

4:1-BALUN-1.5 1.5kW 1.8-30MHz Balun

Price: £54.95 (Including VAT) Good Stock Level
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4:1-BALUN-1.5 1.5kW 1.8-30MHz Balun by M0CVO

The M0CVO Antennas 4:1 Extra High Power 1.5KW current balun for Windom, off centre fed or folded dipoles. 1.5KW RF power handling ability. This is for intermittent amateur use and not for continuous AM broadcast use. Used to reduce the 200 - 300 Ohms at the feed point of the antenna to the 50 Ohms required by your transceiver. This enables the antenna to be fed with standard 50 Ohm coaxial cable.

W-LINE 1:1 Line Isolator 400W 1.8-30MHz

Price: £33.95 (Including VAT) Low Stock - Phone
Quantity:

W-LINE 1:1 Line Isolator 400W 1.8-30MHz by M0CVO

The W-Line 1:1 Line Isolator operates from 1.8 - 30MHz. It will handle up to 400W CW or 450W PEP.

This is used to prevent unwanted stray RF feedback coming into the shack via your feed line. Banish the interference to the other items nearby radios, telephones, etc.

To use, fix the isolator to a convenient point outside this could be a tree trunk, fence post, wall, pole or whatever. Attach the coax from your antenna to one connector on the isolator and then attach a second piece of coax to the other connector and use this to connect to your transceiver or ATU. The insertion loss of this unit is approx 0.02dB so is therefore negligible. It does not affect the SWR / tuning of the antenna at all if you were using an ATU before, it will still be the same.