21LTDST.MANUAL.REV.QX 9/25/98 10:59 AM Page 3

How To Use Your

Citizens Band

 

2-Way Mobile Radio

Model 21 LTD ST

 

Contents

Page

The CB Story

1

SoundTracker System

1

Specifications

2,3

Installation

 

Location

4

Mounting Connections

4, 5

CB Antenna

6

Ignition Noise Interference

7

In House Operation

7

Operation

 

Controls and Indicators

8, 9, 10

Operating Procedure to Receive

11

Operating Procedure to Transmit

12

How SoundTracker Works

13

Maintenance and Adjustment

14

Appendix

 

Ten Code

15

A Few Rules That Should Be Obeyed

16

How Your CB Can Serve You

16

Warranty Service Instructions

17

Limited Two Year Warranty

18

Accessories

Inside Back Cover

The CB Story

The Citizens Band lies between the shortwave broadcast and 10-meter Amateur radio bands, and was established by law in 1949. The Class D two-way commu- nications service was opened in 1959. (CB also includes a Class A citizens band and Class C remote control frequencies.)

FCC regulations permit only “transmissions” (one party to another) rather than “broadcasts” (to a wide audience). Thus, advertising is not allowed on CB Channels because that is “broadcasting.”

“Cuts Static coming in, adds Punch going out!”

Cobra proudly introduces the first Patent Pending technology that dramatically improves the transmission and reception of CB radio signals.

This revolutionary system reconfigures the transmission signal which allows it to be transferred more effectively through cluttered airwaves. It literally “punches” your message through the hundreds of thousands of signals that are in the air. At the same time, SoundTracker system dynamically adjusts the relationship between the signal and static commonly referred to as noise. This allows Cobra’s SoundTracker system to significantly reduce the amount of static on all incoming CB signals. The system can be further optimized when two SoundTracker CB’s are used to talk to each other.

The end result is a clearer, cleaner sounding reception of signals and more powerful transmissions which dramatically improve CB Communications

All transmitter adjustments other than those supplied by the manufacturer as front panel operating controls, must be made by, or under the supervision of, the holder of an FCC-issued general Radio-Telephone Operator’s License.

Replacement or substitution of transistors, regular diodes or other parts of a unique nature, with parts other than those recommended by Cobra, may cause violation of the technical regulations of Part 95 of the FCC Rules, or violation of Type Acceptance requirements of Part 2 of the Rules.

You should read and understand Part 95 (included with this unit) of the FCC Rules and Regulations, before operating your Cobra radio, even though the FCC no longer requires you to obtain an operators license.

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Cobra Electronics 21 LTD operating instructions CB Story, Cuts Static coming in, adds Punch going out
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21 LTD specifications

Cobra Electronics 21 LTD is a versatile Citizen Band (CB) radio designed for seamless communication in a wide array of environments, making it a staple for truck drivers, outdoor enthusiasts, and hobbyists alike. Known for its reliability and quality, the 21 LTD combines advanced technology with user-friendly features, ensuring clear and efficient communication.

One of the standout features of the Cobra 21 LTD is its compact design, which makes it easy to install in trucks, cars, and even boats. Despite its small size, it accommodates a comprehensive 40-channel system, allowing users to select from various frequencies, ensuring they can find optimal communication channels regardless of their location.

Equipped with a powerful, built-in noise-canceling microphone, the 21 LTD is adept at minimizing background noise, producing crystal-clear audio even in noisy environments. This feature is particularly beneficial for truck drivers traversing busy highways, ensuring that both transmitted and received messages maintain high quality. Additionally, the radio boasts Automatic Noise Limiting (ANL) technology, which further enhances sound quality by reducing static and interference.

The Cobra Electronics 21 LTD also includes a front-firing speaker for improved audio clarity and a large, easy-to-read analog gauge for channel selection and signal strength monitoring. This design enhances operational convenience, allowing users to stay focused on the road while effortlessly adjusting settings.

Another notable characteristic is the inclusion of a PA (Public Address) feature, which enables users to connect an external speaker. This is especially useful for communicating with larger groups or providing instructions at job sites. Furthermore, the radio features a built-in SWR (Standing Wave Ratio) meter, an essential tool for ensuring proper antenna alignment and optimizing signal performance.

In terms of durability, the Cobra 21 LTD is designed to endure the rigors of outdoor use, featuring a robust construction that can withstand vibrations and varying weather conditions. With an easy installation process and compatibility with various microphones and accessories, this radio is perfect for both seasoned CB users and newcomers.

In conclusion, the Cobra Electronics 21 LTD is a powerful and reliable CB radio that boasts numerous user-friendly features, advanced technologies, and rugged characteristics. Whether for long hauls, outdoor adventures, or casual communication, the 21 LTD stands out as a top choice for those who value quality and convenience.
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