ANTENTOP- 01- 2011, # 015

Super Broad Band HF- VHF Antenna

Introduction: I desperately need in rx/tx antenna that could be work at HF- UHF bands without any tuning. The antenna should be work at any conditional and should be simple in design. Below you find description of my design of such antenna.

Igor Lavrushov , UA6HJQ

Credit Line:

http://goryham.qrz.ru/ant/hf-wide.htm

From some time I used to an FT857D. This transceiver has not an internal ATU, so, I have to use only matched antenna with this rig. At first I tried a length of a wire in 14- meter going from a window of my balcony to the ground at angle of 50 degree. This wire was matched well at all HF- Bands and allowed me did operation in the Air.

However, soon I understood that the antenna had some disadvantages.

Firstly, when band has changed I have to go to the next with the balcony room to tune up the antenna, secondly, the antenna was too noisy. Figure 1 shows the antenna.

Figure 1 Wire antenna for FT857D

So I decided to design antenna that do not require any tuning and that has no so much noise. It would be possible if the resonance antenna was converted to aperiodic antenna like a T2FD. However I have no place for original T2FD, and I already have installed the 14- meters length of wire, that is why conversation to be applied only to the wire. Figure 2 shows schematic of the antenna. Resistor for 50- Ohm is old surplus dummy load. Counterpoise is a 5- meters length of wire that is placed around perimeter of my balcony. Coaxial cable 50- Ohm from the antenna to FT857D has the 7- meter length.

Figure 2 Aperiodic antenna for FT857D

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