350–450 MHz 2 dBi Black Fiberglass Omni Antenna, N-Male with Spring, KSANT-11283-A

The 350–450 MHz band is where the UHF ISM and telemetry world meets two-way radio, and it includes the widely used 433 MHz ISM band. The demand for one antenna that covers the whole span on a single mast has never been higher. Site planners are constantly challenged to cover equipment in every direction on a band where the radios move around the site, and there is nothing to aim at. The solution lies in a slim fiberglass omni tuned to the whole 350–450 MHz span, with a spring at the connector end for wind and vibration. We are proud to introduce the 350–450 MHz 2 dBi Black Fiberglass Omni Antenna, model KSANT-11283-A, a 670 mm linear-polarized radiator engineered for UHF telemetry, 433 MHz ISM and two-way radio.

This antenna represents a practical answer to a real installation: a single 670 mm radome of 25 mm diameter, weighing 0.52 kg, finished in elegant black and terminated in an integrated N-male connector with a spring relief above the base. The band is covered from 350 to 450 MHz at 50 Ohm with VSWR <2.0, peak gain runs 0–2 dBi, and the horizontal pattern is a full 360° with roundness held to ±1 dB. Power handling is 150 W, the element is DC grounded, and the build is rated for wind of 36.9 m/s across an operating range of −45 °C to +85 °C. It is the practical choice where one slim antenna has to serve UHF equipment in every direction.

Technical Excellence: The Core Advantage

The antenna's performance rests on three pillars: coverage of the 433 MHz span, a spring relief at the base, and a 150 W build for real UHF links.

A 350–450 MHz Span That Covers 433 MHz

The design covers 350 to 450 MHz, which takes in the lower UHF band and the widely used 433 MHz ISM band in a single part. That is the headline value of a wideband UHF antenna: instead of two resonant masts at two sub-bands, one 670 mm radome feeds the radio. Measured gain runs 0.1–2.3 dBi across the band, with efficiency between 67.3% and 76.9%, which is the realistic figure for a dipole-class UHF radiator rather than a high-gain collinear. It is built for coverage and omnidirectional service, not for a long point-to-point hop, and the datasheet says so plainly.

A Spring Relief at the Connector End

The mechanical design is the part that matters on real roofs. Above the N-male connector there is a 65 mm spring relief section, which flexes under wind load and vibration instead of stressing the connector and the feedline. That is the same approach used on marine and vehicle mounts, where the mast has to move in the wind without breaking the connector. The connector is N-male, the standard threaded interface on a mast, and the element is DC grounded so static charge drains to the mast.

Roundness ±1 dB and a Clean Match

The specified roundness is ±1 dB, and the chamber measurements track it closely: 0.30 dB at 350 MHz, 1.10 dB at 400 MHz and 0.73 dB at 450 MHz. The vertical beamwidth is 34–102°, which is broad rather than narrow, matching the way UHF signals arrive from vehicles and ground stations at different heights. The specified match is VSWR <2.0 across the band, and the stored trace marks 1.38 at 350 MHz, 1.25 at 433 MHz and 1.27 at 450 MHz, with return loss of 16.0 dB, 19.0 dB and 18.6 dB at those three points. Maximum power is 150 W, which covers UHF transmitters and multi-carrier radios. The radome is 25 mm in diameter, 670 mm long, elegant black, and weighs 0.52 kg. Mechanical qualification is stated rather than assumed: a ≥200 N tensile test, a 1 m drop test, vibration from 10–55 Hz at 0.35 mm displacement and 50.0 m/s² over 30 sweep cycles, and voltage resistance of 1.5 kV insulation, 1.5 kV sheath and 0.5 kV insulation-to-sheath. The product is RoHS compliant.

Versatile Application Scenarios

The combination of a 350–450 MHz span, a spring relief and 150 W handling makes this antenna useful wherever one UHF mast has to serve equipment in every direction.

433 MHz ISM, LoRa and Telemetry

433 MHz ISM and LoRa gateways: one omni covers a campus, a farm or a site on the 433 MHz band, and the round pattern keeps sensor links predictable around the mast.

Telemetry and remote sensors: industrial, agricultural and pipeline telemetry uses UHF for long range, and one radome replaces several small antennas on the same pole.

UHF Two-Way Radio and Fleet

Fleet and public-safety base stations: one omni covers a depot, a campus or a worksite on the UHF band without sector overlap.

Industrial and mining radio: factories, ports and mines run UHF multi-channel radio, and one wideband radome replaces several narrowband antennas on the same pole.

Outdoor Fixed and Mobile Sites

Street poles and light masts: the 0.52 kg weight and elegant black finish suit wall brackets, parapets and light poles where a panel would look intrusive.

Vehicle and mobile mounts: the spring relief at the base suits vehicle roofs and portable masts, where road vibration and wind load would otherwise stress the connector.

Conclusion: The Future of Wideband UHF Coverage

The 350–450 MHz 2 dBi Black Fiberglass Omni Antenna, KSANT-11283-A, is more than a passive component. It is the part that turns a multi-antenna UHF roof into a single feed. By covering 350–450 MHz at 50 Ohm with VSWR <2.0, holding roundness to ±1 dB across a full 360°, and carrying 150 W behind an N-male connector with a spring relief on a 670 mm black radome, it gives site planners a mast they can predict before the survey. The 0.52 kg weight, 36.9 m/s wind rating and −45 °C to +85 °C operating range state its limits up front. For any UHF deployment that needs one antenna to serve 433 MHz and the surrounding band, this antenna is the practical choice.