4282 NVIS Tilt Whip Adaptor

NVIS Tilt Whip Adaptor

The purpose of NVIS (Near Vertical Incident Signal) is to enable communications in the area commonly called the “Skip Zone” or “Dead Area.” This is accomplished by tilting the antenna so that its main radiating lobe is 73° to 83° above the horizon. The higher radiating lobe causes the signal to bounce off the ionosphere, returning to the earth in the dead area that may occur 10 to 150 miles out when using the antenna vertically.

The HF band is home to the most effective frequencies for NVIS applications: 4 to 12 MHz. Shakespeare’s Model 120 system is NVIS-ready. The antennas can be mounted on a base, such as Model 4289-W Spring Base, which has tilt features built in, or adapted by inserting an adaptor between the antenna and the base. In either case, the High Voltage Protection Device can still be used. For information about NVIS using Tilt Whip adaptors contact Shakespeare. See 4282 NVIS Tilt Whip Adaptor Data Sheet for more information.

• Tilt Adaptor screws onto base, and antenna screws onto adaptor.
• Locking knob prevents rotation of adaptor
• Use with 16′ or 32′ antenna
• Forward or reverse tilt
• Spring-loaded locking pin permits quick change of tilt settings: at vertical, 50°, 70°, and 90°
• Height: 19″ nom. (adaptor only)
• Use with 120-HVPDR for high voltage protection
• Fits 120-28, 4245, or 120-43 bases

 NSN: 5985-01-422-8525