BUTTERNUT - HF2V - HIGH PERFORMANCE HF 2-BAND SPECIALISTIC VERTICAL ANTENNA FOR 40-80 METERS
- POSSIBILITY TO ADD 30 AND 160 METERS WITH OPTIONAL KITS -
TECHNICAL SPECIFICATIONS:
- Height: 9.75 m (32 ft)
- Input impedance: 50 ohm nominal
- S.W.R. resonance: 1.5:1 on all ranges in typical ground or roof installation
- Bandwidth (within 2:1 S.W.R):
- 40 m - the whole ham band
- 80/75 m - 90 kHz
- Applicable power: 2000 Watt P.E.P. SSB on all bands (@1:1 S.W.R.)
- Exposed wind area: 0.49 sqm.
- Wind resistance: 97 km/h (60 mph) without guy wires
- Shipping Weight: 6 kg
NOTE:
The above bandwidths are what would be expected on ground systems of better than average conductivity.
Bandwidths can be greater on below average ground systems.
The HF2V comes complete with a lower support of approximately 2" long and 1.125 "outside diameter, for easy insertion into a standard 1.25" diameter steel pole or ground or optional MPS stand.
Resonance inductances for 40 and 80 meters can be adjusted at eye level. The inductors for 75/80 and 40 meters consist of a 3/16 inch diameter aluminum conductor, are wrapped in air and are self-supporting. Typical spacing between adjacent coils is 1/2 inch or greater.
Why are the Butternut HF2V multiband antennas far superior to other similarly sized multiband verticals, however they are designed, or whatever the number of bands offered, or whatever their price is?
It is very simple to answer such a question.
Conventional designs make use of trap-based circuits to interrupt the flow of current in the upper portions of the antenna on all but the lowest in frequency bands.
The result is therefore an antenna that reaches the fateful theoretical value of a quarter wave only on 10 meters. On the lower frequency bands, on the other hand, the cumulative load of the traps relative to the higher frequencies limits the amount of conductor that can be used for resonance, with the consequence that the radiation resistance values are progressively lower, even on those bands in which the available conductor has a length greater than a quarter wave.
The radiation resistance is that portion of the total impedance of the antenna at the power point that represents the useful part, that is the power actually radiated by the antenna instead of lost in heat in the traps or in the charging coils or in the ground connections.
The secret of the efficiency of a vertical antenna lies in keeping the radiation resistance at the highest possible value in relation to the losses in the earth or in the conductor.
Butternut's unique (Patented) Differential Reactance Tuning System makes the entire radiator element of the 9.75 meter vertical antenna resonate across all bands.
This implies a higher radiation resistance and consequently a greater efficiency than can be obtained with conventional verticals with multiple traps of the same length and operating on the same ground plane.
There are also many other advantages deriving from a greater radiation resistance obtained thanks to longer radiating elements, among which a greater bandwidth within values of S.W.R. much more contained and a greater radiation of the signal at lower wave angles, that is those useful for DX connections.
Try to compare the passband on a central frequency and the DX rendering with low angle signals between the Butternut verticals and other trapped multiband verticals: you will see for yourself that there is really no comparison!
The secret always lies in the type of exclusive design, which offers greater radiation resistance thanks to the use of LC reactance generating circuits, each consisting of conductors wound in air in the shape of a coil, of such diameter as to be self-supporting, and arranged in suitable points of the antenna with high-voltage ceramic capacitors, for the highest possible Q and the lowest possible losses in the conductor and in the dielectric.
Thanks to the use of the TBR-160-S OPTIONAL KIT, all Butternut verticals can be successfully resonated even on 160 meters, and the range change from one band to another does not require recalibration, but is totally automatic.
The HF2V can operate, by adding the appropriate KIT 30-MRK, even on 30 meters.
Additional bandwith and performance can be achieved by adding the TLK, Top Loading Kit (OPTIONAL), but please note that this KIT is not compatible with the 30-MRK KIT: you have to choose one OR the other.
NOTE:
- The 30-MRK kit can only be installed ALONE. It is not compatible with the TBR-160S or the TLK kit.
