TH-3JRS Tri-band HF 3 Elements Beam Covers 10, 15 and 20 Meters
The Hy-Gain TH-3JRS is a tri-band HF 3-element beam antenna designed for 10, 15, and 20 meters. Constructed of taper-swaged aluminum tubing with stainless steel hardware, it features low wind resistance and is suitable for rooftop or lightweight tower installations. The antenna accepts masts up to 2 inches in diameter and can be rotated with heavy-duty TV rotators like the Hy-Gain AR-40 or CD-45II.
The manual details step-by-step assembly, including the installation of boom sections, reflector, driven element, and director elements using specific trap assemblies for each band. It covers three feedpoint configurations: direct connection, homemade RF choke construction, and the use of a 50 ohm 1:1 balun (recommended: Hy-Gain Model BN-86). Installation includes weatherproofing connections and securing the boom-to-mast clamp.
| Frequency Coverage | 10, 15 and 20 Meters |
|---|---|
| Forward Gain | Up to 8 dBi |
| Front-To-Back Ratio | 25 dB |
| VSWR at Resonance | Less than 1.5:1 |
| Nominal Impedance | 50 ohms |
| Power Capability (PEP) | 600 Watt |
| Power Capability (AM) | 300 Watt |
| Net Weight | 21 lbs. (11.7 kg) |
| Wind Survival | 80 mph (128 kmph) |
| Accepts Mast Diameter | 1 ¼" to 2" (32 mm to 51mm) |
The antenna can be rotated with a heavy-duty TV rotator, specifically the Hy-Gain AR-40 or CD-45II.
The Hy-Gain Model BN-86, 50 ohm balun is recommended for increased performance and convenience.
The recommended feedline is RG-213/U, such as Belden 8267.