HW4 Mobile HF Antenna 1.8 - 30MHz
SMC have designed the HW4 series as an efficient HF centre loaded spot frequency mobile antenna capable of being used without an antenna tuning unit. Where a second or third frequency is to be used, it is only necessary to unscrew the loading coil/whip combination and replace with a pre tuned assembly.
Medium power capability permits an unobtrusive slimline format for either wing, bumper or vertical panel mounting, to provide reliable HF communications under the most arduous conditions.
The resonator and whip sections are individually made and calibrated to your specified frequency; additional frequency allocations need only another resonator and whip section which we can normally supply within days.
Although resonators are supplied to a specific frequency, adjacent frequency working may be used as shown within the specifications.
The HW series antennas have proved themselves over many years in the role of vital communication links to authorities worldwide.
Technical Specification
| Maximum power | 100w 1.5MHz to 3.0MHz | ||
| Capability | 150w 3.0MHz to 30.0MHz rated SSB duty cycle | ||
| VSWR | Typically less than 1.5 : 1 at resonance | ||
| Impedance | Nominal 50 ohm (somewhat less at lower frequencies).Impedance matching networks not normally needed for valve or solid state amplifiers | ||
| Bandwidth | For 2.1 VSWR better than: | ||
| 20kHz at 1.5MHz | 150kHz at 10MHz | ||
| 40kHz at 3.0MHz | 300kHz at 22MHz | ||
| 80kHz at 7.0MHz | 500kHz at 30MHz | ||
Mechanical Specification
| Mast Section | Fibreglass with non ferrous fittings 318" UNF stainless steel screw fitting for base mount. Partial inductive loading on mast with whole enclosed in tough black PVC heat shrunk sleeve. | ||
| Resonator/Whip Section/Former | Non ferrous metal fittings on high impact resistant formers. Lengths vary from 13 " at 1.5MHz to 6 " at 30MHz. Individual wound and calibrated, coated 100% polyurethane,finished with tough black PVC sleeve. Resonator supplied with stainless steel whips to order. | ||