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Original antennas made in the US, by us, for the greater World

Price: $174.24

Typical leadtime if item is not in stock: Approx 7 days (call for stock status)


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    Full-Size Amateur Radio Satellite QFH Antenna description

    The UC-4364-531 is a full-size Quadrifilar Helix Antenna (8 cm/3" OD x 30 cm/12" H) designed to operate through Amateur Radio satellites, without requiring an antenna rotator. The goal of this product is to offer Amateurs with space or community restrictions the ability to receive 70 cm HamSat signals, and communicate through orbiting repeaters (transponders). Ham satellites operate cross-band: you will generally need a VHF uplink transmit antenna for 2-way communications. A companion VHF unit is available UC-1464-531.

    Models UC-4364-531 and predecessor UC-4364-328 are comparable in performance. The -531 version provides a net 1 dB advantage. Both have stable axial ratios and performance across the 70 cm UHF amateur Radio band. For users interested in a narrower beamwidth and higher gain applications, such as Rocketry telemetry/control, or users using an AZ/EL rotator, gains up to +8 dBic can be realized with the -328 model and a modest Ground Plane/Reflector. Additional information may be requested via email (we intend to post a PDF document with such data on this page and all -328 and -531 model pages by May 2021).

    Although this antenna belongs to the -531 series by its electrical design characteristics; Mechanically, it is compatible with the -328 series accessories. "Related Products" at the bottom of this Description links to the correct associated products within our catalog.

    Useful OSCAR relevant information

    Useful web pages about Amateur Satellites and relevant information are below:

    UC-4364-531 QFHA Technical Specifications

    • Frequency range: 435-438 MHz
    • Coverage: Omni-directional, Hemispherical
    • Polarization: Circular (AR 1 dB)
    • Gain: +4 dBic
    • Nominal Impedance: 50 ohm (RF), Short Circuit (DC)
    • Input Power: Maximum 50 W CW
    • VSWR: Under 2.0
    • Connector: SMA Female, on the side of cylindrical housing, just above the flange base. Cable assembly may be purchased separately SMA Cables
    • Dimensions:
      • Housing 8 cm (3") OD x 30 cm (12") h
      • Bottom flange 10 cm (4") OD x 10 mm (0.38") h
    • Mounting: 4 screws, M4 (#10-32)
    • Operating Temperatures: -40°C to +85°C
    • Weight: 1.5 kg / 3.2 lbs
    • Shipping Weight: 1.7 kg / 3.6 lbs


    • Does not require a ground plane
    • Specifications and prices are subject to change without notice
    Availability, specifications & prices subject to change without notice