Marker Beacon Antenna
75 MHz
SKU: 21-20-79
The 21-20-79 is a lightweight Marker Beacon Antenna suitable for Instrument Landing Systems (ILS) installations on helicopters and subsonic aircraft. Its rugged design uses a printed circuit radiating element enclosed within a lightweight glass reinforced composite shell which in turn is bonded into a machined aluminum alloy base plate. This method of construction avoids base delamination problems associated with some other manufacturers designs.
- Lightweight
- Small physical size
- No tuning require
- Designed to MIL-STD-810 environmental conditions
- DC Grounded antenna element
- Direct replacement for NSN 5985-99-723-2258
21-20-79 | |
Model # | 21-20-79 |
Brand | Cooper Antennas |
Frequency | 75 MHz ± 10 kHz |
VSWR | ≤ 3.0:1 |
Impedance (nominal) | 50 Ohms |
Polarization | Predominantly Horizontal |
Radiation | Downward lobe |
Antenna RF Connector | BNC Female |
Construction | Fiberglass shell/ Aluminum base |
Height | 1.9 inches (48.3mm) |
Length | 9 inches (228.6mm) |
Weight | 0.75 lb (0.34kg) max |
Base Plate Shape | Oval |
Fixing Holes | 0.234 / 0.208 inches (5.9 / 5.3mm) holes , counter bored 0.5 inches (12.7mm) |
Finish
- Urethane Gloss White
- Other finish options are available.
- Please specify finish required when ordering.