Broad Band Terminated Dipoles (BBTD), Tilted Terminated Fold Dipoles (T2FD) and Balanced Termination Folded Dipole BTFD) antennas can be designed to cover a large range of frequencies between 1.8 30 MHz. Longer length antennas generally provide better low frequency efficiency but take up a larger footprint of land. One BBTD that has worked well at the AK6R antenna farm is shown below. Many other designs are available and can be found at www.HFLINK.COM as well as other internet sites. Your mileage may vary using this antenna, but as a general coverage antenna for ham and shortwave broadcast, the simplicity can’t be beat even though an individual dipole on a specific band may out perform this broad band dipole. Palomar Engineers has all the parts you need to build this antenna, so why not give it a try?
Depending on the source of the antenna design, different value baluns are specified. Our Bullet(TM) baluns in ratios of 9:1, 12:1 and 16:1 are excellent for this type of antenna as they are broadband from 1.8-61 MHz and will take up to 500 watts PEP.
High Power rated at 1.5KW/3KW/5KW (option) PEP (FT8 mode at 1.5KW)
Broad frequency range of 3-30 MHz for < 2:1 SWR into matched load
Compact 4" x 4" x 2" (1.5KW) or 4" x 4" x 4" (3KW/5KW) light weight weatherproof enclosure
Quick, easy deployment with either halyard hoist and side eyebolts or to stud outputs (all 1/4" stainless hardware)
Choice of BALUN (balanced outputs) or UNUN (unbalanced output and ground)
Model CB-2.25-1500, 3000, 5000 is a 2.25:1 (112:50 ohm) multi-core balun used to translate a 50 ohm input to 112 ohms at RF power levels up to 5000 watts PEP when used with a matched load such as single band delta loop, quad or loop skywire. This assembled balun features a multi-core configuration for increased power handling and flatter frequency response to over 30 MHz. With a matched 112 ohm load the SWR over the frequency range is very consistent from 3-30 MHz and SWR is less than 2:1 over the range allowing easy tuning by most radio internal antenna tuners or an external tuner.
Likewise Termination Resistor values vary from 500-1250 ohms and we have a good selection shown HERE: