1/2 UNUN for short low band verticals.
It is generally known that vertical antennas are the best choice for working DX on the low amateur HF bands. (Especially as TX antennas).
In many cases, because of the long wavelength it is not practical to erect full size antennas for 160m and 80m, and some type of loading is required to shorten the antenna.
Capacitive top loading, using “loading wires” is recommended, both electrically and mechanically.
Examples are top loaded quarter wave verticals , “Vertical T monopoles” and “Inverted L” antennas.
A consequence of shortening the antenna by means of loading is a lowered radiation resistance at resonance.
Values of 25 Ohms and less are common, which cause high VSWR when feeding the antenna directly.
In order to match the antenna, often an ½ UNUN is used, which presents a “plug and play” solution.
A 1/2 UNUN ensures that within the range of 17 to 30 Ohms, the resulting VSWR does not rise above 1.5/1 which allows comfortable operation with a normal TRX or linear amplifier.
We can provide 1/2 UNUN’s optimized for the low HF bands.
- Frequency range: 1 to 11 MHz.
- Maximum Power: 1200W PeP @ VSWR <2,0/1, (ICAS)
- Insertion Loss: < 0.1 dB
- Polycarbonate enclosure.
- Stainless Steel hardware.
- Mounting option included.
Price: 98 Euro.
- Option N-connector (N-connector instead of SO239): + 6 Euro.