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How do you make an OCF dipole?
To build the OCF dipole (in this case 80-10m) cut a single length of wire to an overall size of 133′. The 3 additional feet of wire will be used to fine-tune the OCF after you install it. Next, cut the 133′ into two separate lengths of 85′ 2 ½“ and 47′ 9 ½”.
What is OCF antenna?
This type of antenna is a popular antenna design as the performance is very good across the HF bands and requires little or no tuning. It’s a dipole fed off center with a 4:1 balun at the offset feed point. The antenna shown covers 80, 40, 20 and 10 meters.
What is center fed antenna?
The half-wave center-fed dipole is one of the most popular antennas in use today. In free space the center-fed half-wave antenna has an input impedance that is a close match to 50 ohm coax and to most radios that have a 50 ohm output impedance. It can be installed as an inverted V or as a straight dipole.
What is antenna Balun?
A balun (balanced line to unbalanced line) is a device that transforms a balanced transmission line to an unbalanced transmission line. Baluns are hooked up to antenna systems to help electricity run smoothly from the ground to the device.
Which is off center fed ( OCF ) antenna?
OCF antennas are very convenient as they will allow multiple bands of operation with a simple wire antenna which is fed off center with a 4:1 OCF Current balun with built in feed line choke,
How big is an OCF dipole antenna antenna?
The OCF Dipole antenna is very simple. As already mentioned it is fed at the 1/3 point. So for 80m and up, you have one leg that is 45 feet long, and another leg that is 90 feet long. Some tweaking may be needed, but mine was built within an inch or two of those measurements.
What kind of conductor does An OCF dipole use?
OCF dipole is an ungrounded dipole antenna fed with twin-conductorline, either coaxial or open wire parallel conductors. The so-called “OCF windom” is also a misnomer, for the same reasons.
Can a vertical radiator be used in An OCF antenna?
No vertical radiator is used in the OCF antenna. Note that if you want to use a vertical radiator (ala Carolina Windom), then you will need to use a 4:1 voltage balun r ather than a current balun so that some of the RF fed to the antenna feed point will go down the feed line through the vertical element and give some vertical polarized output.