BUTTERNUT - HF9V - HIGH PERFORMANCE HF 9-BAND VERTICAL ANTENNA FOR 6-10-12-15-17-20-30-40-80 METERS
The HF9V is practically the same as a HF6V with the 6-12-17 meter kits added in the box
TECHNICAL SPECIFICATIONS:
- Height: 7.9 m (26 ft)
- Input impedance: 50 ohm nominal on included tuning line
- S.W.R. resonance: 1.5:1 on all ranges in typical ground or roof installation
- Bandwidth (within 2: 1 S..W.R):
- 10 m - 1500 kHz
- 15 m - the whole range
- 20 m - the whole range
- 30 m - the whole range
- 40 m - 280 kHz
- 80/75 m - from 40 to 100 kHz
- Applicable power (@1:1 S.W.R.): 2000 W P.E.P. SSB on 10-80 meters , 800 W P.E.P. on 12 & 17 meters, 500 W P.E.P. on 6 & 30 meters
- Exposed wind area: 0.49 sqm.
- Wind resistance: 128 Km / h without guy wires
- Shipping Weight: 6.75 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 HF9V comes complete with a lower support of approximately 79 cm 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, 80 and 30 meters can be adjusted at eye level. The 15 and 10 meters are regulated by varying the length. The tuning on 20 meters is a function of that of 30 and 40 meters. The inductors for 75/80, 40, and 30 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.
You can immediately understand why the BUTTERNUT verticals offer much more than other typical trapped verticals by studying the active lengths of the elements:
|
BAND
|
HF6V
(wavelenght)
|
TIPICAL TRAPPED VERTICAL
(wavelenght)
|
|
10M
|
0.75
|
0.23
|
|
15M
|
0.26
|
0.21
|
|
20M
|
0.375
|
0.17
|
|
30M
|
0.264
|
n.a.
|
|
40M
|
0.189
|
0.145
|
|
80M
|
0.097
|
0.094
|
Why are the Butternut HF6V and HF9V 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 7.9 meter vertical antenna resonate across all bands, with the exception of 15 meters.
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. Even on 15 meters, however, the active part of the Butternut verticals is significantly greater (a full quarter wave or more) than any other comparable vertical antenna with traps.
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 10 to 160 meters does not require recalibration, but is totally automatic.
The HF6V can operate, by adding the appropriate KIT A-17-12, even on 12 and 17 meters.
By adding the KIT A-6 it can also operate on 6 meters, thus becoming an HF9V, which is nothing more than a HF6V with the additional kits supplied as standard.
