Off Center Fed (OCF) 4:1 Balun and 1:1 Balun Combo, 1.8-61 MHz, 1.5/5KW PEP Option

Name: Off Center Fed (OCF) 4:1 Balun and Choke Combo, 1.8-61 MHz, 1.5/3/5KW PEP
Brand: Palomar Engineers
SKU: CB-4-1500OCF
Price: 149.95 USD
Availability: InStock
Rating: 5.0 (1 reviews)

5.0

1 review

Store/Antenna Products/CUBE Impedance Transformers (<1:1, 1:1, >1:1)/Off Center Fed Dipole Transformers

SKU CB-4-1500OCF

$149.95

Bulk pricing available for quantities of 2 units or more

PEP Power Rating Select

1.5KW PEP Watts

5KW PEP watts (+$100.00)

Quantity:

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Quantity	Price per item	Discount
2 items	$137.95	8% off
10 items	$124.95	17% off

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JAMES D.

Roxboro,

United States

Aug 13, 2025

This is just exactly what the amateur radio operator would require for their OCF antenna (yes, I have one of your 135 fee is multi-band OCF dipoles). The purchase came with another 4:1 balun and following 1:1 balun. This second is for a compact 68 foot OCF that I am currently building. With the performance of the 135 foot, I know that this is essential for the compact build. TNX 73 de KI4HQO Jim D,USA, Roxboro, NC

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Off Center Fed (OCF) 4:1 Balun and 1:1 Balun Combo, 1.8-61 MHz, 1.5/5KW PEP Option

Store/Antenna Products/CUBE Impedance Transformers (<1:1, 1:1, >1:1)/Off Center Fed Dipole Transformers

Product Details

MPN: CB-4-1500OCF, CB-4-3000OCF, CB-4-5000OCF

Country/Region of Manufacture: USA

Input ohms/Output ohms: 50 in/200 out

Frequency Range < 2:1 SWR (MHz): 1.8-61 MHz for 1.5KW, 1.8-31 MHz for 3KW/5KW

PEP Power Rating (watts): 1.5KW/3KW/5KW

Enclosure Size: 4"x4"x 2"(1.5KW), 6"x 6" x 4"(3KW/5KW)

Weight (pounds): 3(1.4KW)/4(3KW)/5(5KW)

1500 Watt PEP rated 4:1 Current Balun + internal 1:1 Current Balun in one enclosure

After many requests we have created a compact, special balun for OCF and loop (Skyloop or Delta loop) antennas. The CB-4-1500OCF is a CUBE enclosure containing a multi-core, broadband 4:1 impedance transformer in series with a 1:1 current balun for extra common mode current choking to keep RF current off the outside of the coax braid and on the antenna where it belongs. The extra choking action also means that the coax feed line will not act as a radiator causing unnecessary RF interference (RFI). Rated for full 1500 watts PEP and 450 watts CW/FT8/RTTY (ICAS). 1.8Mhz – 61 MHz.

The CB-4-5000OCF (5KW PEP) have a frequency range of 1.8-31 MHz and does not cover 6 meters.

CB-4-1500OCF is housed in a 4” x 4” x 2” waterproof housing with SO-239 input and stainless steel eye bolts on the side for ease of connection to your wire antenna. Top eye bolt acts as an antenna hoist. Use this balun combination when you DO NOT have a vertical radiator.

5KW are in 6" x 6" x 4" enclosure. 1.5KW is 3 pounds, 5KW is 5 pounds. Note the 5KW models are made to order and shipment time is approximately 7-10 days after order date.

For a 135 foot 80 meter OCF, we recommend a 29.5%/79.5% offset for best all band results. If you use 66%/34% offset, do not use on 15 meters as the impedance mismatch may damage the balun under high power operations

Learn all about OCF Antennas in our FREE DOWNLOAD: OCF ANTENNA CONFIDENCE