Diamond Antenna NR7900A Instructions

NR7900A

2m/70cm Mobile Antenna-High Power

Instruction Sheet

The NR7900A is a high performance dual-band mobile antenna. The NR7900A will handle
300 watts on 2m and 250 watts on 70cm. Use Diamond Antenna model K400C or K600M
Trunk Mount, for best performance.

Specifications

FREQUENCY: 144-148; 440-450 MHz
GAIN: 3.7 dB (2m); 6.4 dB (70cm)
POWER: 300 Watts (2m); 250 watts (70cm)
IMPEDANCE: 50 Ohms (Nominal)
VSWR: 1.5:1 (Nominal)
ELEMENT PHASING: 6/8 Wave (2m); 2-5/8 wave (70cm)
LENGTH: 58”
WEIGHT: 1.75 lbs. (700g)
MOUNT: UHF MALE
WARRANTY: 1 Year against defects in material or workmanship.

RECOMMENDED MOUNTS: K400C, K400S, K600S or K600M

Installation Instructions

(1) Remove antenna from package and inspect contents to insure it is complete.

(2) Choose desired mounting location to insure maximum strength of mount, and best
performance of antenna.

(3) Assemble upper whip element #020701 to Phase inductor #020702.

(4) Install antenna on vehicle. With quality VSWR meter, check VSWR for proper an­tenna tuning. The NR7900A is pretuned and should require no additional tuning. However,
choice of antenna mount and location should take into consideration the antenna’s size and
the torque imparted to its mount. Mounts of sufficient strength are Diamond models K400C,
K400S, K600S and K600M.

(5) Tighten setscrews. Recommend using removable Loctite Threadlocker #242 or simi­lar product to insure proper fastening of setscrews.

NOTE: Not recommended for Magnet Mounts.

020709

020708

020701

020702

020703

020704

020705

020706

020707

VSWR

144MHz

144MHz 146MHz 148MHz

440MHz

440MHz 445MHz 450MHz

DIAMOND ANTENNA Products are distributed by RF PARTS COMPANY

Part # Part Description

020701 Upper Whip Element
020702 Upper Phase Coil
020703 #2 Element
020704 Lower Phase Coil
020705 #1 Element
020706 Fold Over
020707 Base Coil
020708 Set Screws
020709 Hexagonal Wrench

435 S. Pacific Street • San Marcos, CA 92078 • [phone]

www.diamondantenna.net