Off Center Fed (OCF) 4:1 Balun and 1:1 Balun Combo, 1.8-61 MHz, 1.5/5KW PEP OptionProduct DetailsMPN: CB-4-1500OCF, CB-4-3000OCF, CB-4-5000OCFCountry/Region of Manufacture: USAInput ohms/Output ohms: 50 in/200 outFrequency Range < 2:1 SWR (MHz): 1.8-61 MHz for 1.5KW, 1.8-31 MHz for 3KW/5KWPEP Power Rating (watts): 1.5KW/3KW/5KWEnclosure 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
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
Christmas lights or yard lights with switching DC power supplies are often the RFI source and a clamp on ferrite bead on the AC AND the DC side feeding the lights is needed to help suppress the switching power supply RFI noise. Suitable snap on beads are FSB31-1/2 for the 1-250 MHz range.
We have also had reported wireless HDTV boxes, and FOSCAM and AMCREST security camera systems causing RFI to garage door remote openers. Use our Garage Door Opener RFI kit to suppress the interference to the opener (VICTIM) – you need one kit for each opener. Maximize the distance from the camera to the openers may also help. Additionally shield cable to the garage door sensors may be needed depending on severity of the camera RFI.
Obvious Tech Note: make sure your remote batteries have enough energy to activate the GDO or the signal they transmit may not be large enough to over ride the RFI signal, but a fresh battery may be able to overcome the weak RFI source and allow the GDO to operate correctly.