Humminbird AS 21RD4KW 21" HD Radar

Humminbird AS 21RD4KW 21" HD Radar

Humminbird AS 21RD4KW 21" HD Radar

B&H # HUAS21RD4KW MFR # 408560-1
Humminbird AS 21RD4KW 21" HD Radar

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Expected availability: 2-4 weeks 
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Product Highlights

  • Up to 4kW Transmit Power
  • 4° Horizontal, 25° Vertical Beam
  • Adjustable VRM and EBL Functions
  • AIS and MARPA Tracking
  • Dual Guard Zones
  • Automatic Gain/Sea Clutter Control
  • Sector Blanking
  • True Palette
  • Zero-Latency Ethernet Connectivity
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Official Rules


NO PURCHASE IS NECESSARY TO ENTER OR WIN. The B&H $1,000.00 Giveaway (the "Giveaway" or "Sweepstakes") is void where prohibited by law and is sponsored by B&H Foto & Electronics Corp., 440 Ninth Avenue, New York, NY 10001 ("Sponsor"). It is not sponsored or endorsed by Facebook or Twitter in any way.

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  • 1Description

The AS 21RD4KW 21" HD Radar from Humminbird helps you navigate through dark and foggy skies, busy shipping lanes, and less than ideal weather situations when used with a compatible fishfinder. The AS 21RD4KW can display a clear radar presentation or a chart display with radar overlay and target tracking. With zero-latency Ethernet connectivity, your compatible display will provide you with real-time target location and detection and long and short-range scales.

Dual Guard Zones
Establish up to two guard zones (sector or circular), and monitor any radar target within each zone.
Automatic Gain/Sea Clutter Control
See only what you need to with this dynamic filter that automatically or manually eliminates screen clutter caused by rain and sea returns.
Sector Blanking
Disable radar transmission over a defined arc to avoid the fly bridge area, or reduce reflections from fixed objects on your boat.
True Palette
View the relative density of targets in eight different colors using this presentation option.
Adjustable VRM and EBL Functions
Adjustable VRM (Variable Range Marker) places an electronic mark or ring over a target on your radar display, and an EBL (Electronic Bearing Line) displays your relative bearing to the target.
AIS and MARPA Tracking
Automatic Identification System (AIS) electronically exchanges data with other vessels, helping to avoid collision. Mini-Automatic Radar Plotting Aid (MARPA) allows you to select targets and track their cource, bearing, and speed, also helping to avoid collisions.
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In the Box
Humminbird AS 21RD4KW 21" HD Radar
  • 4 x Lock Washers
  • 4 x Flat Washers
  • Adapter Cable
  • 4 x M10 x 25mm Hex Metric Bolts
  • 2 x 8A Fuses
  • Limited 1-Year Warranty
  • Table of Contents
    • 1Description
    Antenna Dimensions Enclosed radome: 19.7" (50 cm)
    Peak Power Output 4 kW
    Frequency 9445 +/- 30 MHz
    Beam Width Horizontal: 4°
    Verical: 25°
    Sidelobes Better than -20 dB
    Rotation 24 rpm
    Pulse Length Short: 0.1 uSec / 2000 / Hz
    Medium 1: 0.25 uSec / 2000 / Hz
    Medium 2: 0.5 uSec / 1000 / Hz
    Long: 1.0 uSec / 500 / Hz

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