BIG SIGNAL 3BS-15
3-element full-wave Cubical Quad for high-performance DX on 21 MHz / 15 meters
The BIG SIGNAL 3BS-15 is a 3-element full-wave monoband directional antenna specifically developed for operators looking for a higher level of gain, directivity and weak-signal performance on the 21 MHz / 15-meter band.
Its closed-loop architecture and horizontal polarization combine high electrical efficiency with a well-defined directional pattern, making it an excellent choice for DX, contesting and stations focused on long-distance communications.
Band: 21 MHz / 15 m
Type: monoband directional Cubical Quad
Elements: 3 full-wave loops
Gain: 9.10 dBi free space
F/B ratio: 25.80 dB
Beamwidth: 61° at -3 dB
Polarization: horizontal
Recommended use: DX / contesting / weak-signal / high-performance stations
Why Choose the BIG SIGNAL 3BS-15?
• Three full-wave elements
The 3BS-15 uses three closed full-wave loops specifically optimized for 21 MHz. This configuration is designed to make efficient use of each element without relying on traps, loading coils or physically shortened radiators.
• 9.10 dBi of gain on 15 meters
Its three-element configuration provides 9.10 dBi of free-space gain, delivering a significant step up in performance for stations seriously focused on DX on 21 MHz.
• Excellent front-to-back ratio
With a 25.80 dB F/B ratio, the 3BS-15 provides strong rejection of signals arriving from behind the antenna, helping improve selectivity and reduce interference from unwanted directions.
• 61° beamwidth for well-defined directivity
Its 61° -3 dB beamwidth helps concentrate transmitted and received energy toward the desired area while maintaining practical angular coverage for DX operation.
• Clean reception for weak signals
The closed-loop geometry, combined with the antenna's directivity, can provide favorable signal-to-noise performance in the presence of certain types of electrical interference, particularly useful when working signals close to the receiver noise floor.
• Designed for long-distance communications
The combination of gain, horizontal polarization and directivity is especially well suited to taking advantage of 15-meter propagation and working DX stations over long distances.
• Compact turning radius for its performance level
With a turning radius of 12.63 ft (3.85 m), the 3BS-15 maintains an especially attractive balance between directional performance and required rotational clearance.
• Reinforced construction for permanent installations
Its structure uses a heavy-duty boom, reinforced spreader supports, stainless-steel hardware and specially designed fiberglass components to provide rigidity, mechanical stability and long-term outdoor durability.
• Direct 50-ohm feed
The antenna features a direct 50-ohm feed, making it easy to integrate into high-performance stations and systems designed for high-power operation.
A Step Up in Performance for 15 Meters
The BIG SIGNAL 3BS-15 is aimed at operators looking to move beyond a basic directional antenna. Its three full-wave elements provide a combination of gain, rear rejection, directivity and clean reception designed for high-performance DX stations.
• 3 full-wave elements.
• 9.10 dBi free-space gain.
• 25.80 dB front-to-back ratio.
• 61° -3 dB beamwidth.
• Up to 5,000 W PEP.
• Turning radius of 12.63 ft (3.85 m).
• Direct 50-ohm feed.
• Specifically designed for DX and contesting on 15 meters.
Three Elements. 9.10 dBi. Built to Reach Farther on 15 Meters.
The BIG SIGNAL 3BS-15 combines three full-wave elements, 9.10 dBi of gain and a 25.80 dB F/B ratio in an antenna developed to get more from DX on 21 MHz.
Technical Specifications
Band: 21 MHz / 15 m
Elements: 3
Gain: 9.10 dBi (free space)
F/B ratio: 25.80 dB
-3 dB beamwidth: 61°
Polarization: horizontal
SWR: 1.1:1 ~ 1.5:1
Impedance: 50 Ohms
Maximum power: 5,000 W PEP
Boom length: 18.04 ft (5.50 m)
Turning radius: 12.63 ft (3.85 m)
Overall height: 12.30 ft (3.75 m)
Weight: to be confirmed
Wind survival: > 93 mph (> 150 km/h)
Wind load: 11.03 ft² (1.025 m²) | 180.7 lbf (804 N) | @ 74.6 mph (120 km/h)
9.10 dBi and 25.80 dB F/B for serious DX on 21 MHz
The BIG SIGNAL 3BS-15 combines 9.10 dBi of gain, a 25.80 dB front-to-back ratio and a 61° -3 dB beamwidth, providing a directional pattern especially well suited for DX communications and weak-signal work.
Construction and Materials
• Boom-to-mast plate
Heavy-duty 9.84 x 5.91 x 0.31 in (250 x 150 x 8 mm) structural plate, sized to provide a strong and stable connection between the boom and mast.
• Heavy-duty boom
Round 3.15 in diameter x 0.079 in wall (80 x 2 mm) tubing, designed to provide the rigidity required for a three-element directional structure with an overall boom length of 18.04 ft (5.50 m).
• Spreader support system
Constructed from 1.18 x 0.20 in (30 x 5 mm) angle profiles.
• Fasteners and hardware
Made from W4 stainless steel, selected to provide high mechanical strength, corrosion resistance and long-term durability in permanent outdoor installations.
• Fiberglass system
Custom-made fiberglass tubing with a half-round (semicircular) cross-section rather than conventional round tubing, specifically designed to fit the surface of the spreader supports. Reinforced with fiberglass fabric and UV protection for increased mechanical strength and long-term outdoor durability.
• BIG SIGNAL Wire by Messi & Paoloni
Special copper wire with a polyethylene (PE) jacket, selected to provide excellent weather protection and high mechanical strength.
• Feed system
Direct 50-ohm feed, designed for a maximum power of 5,000 W PEP.
The purchase of the products is always made on request. We manufacture all products, so manufacturing times can be added. That is why the final price of the purchase, as the final price of the shipping costs will be confirmed in an email sent afterwards.
The form of payment will be made once the email is received, so at all times you can cancel the order informing us of the process.
ES
EN
No reviews for this article yet. Be the first to add one.