21-1574.fm Page 17 Thursday, May 13, 1999 4:03 PM

MAXIMUM RANGE

The maximum range and quality of CB transmissions vary depending on the fol- lowing typical conditions:

•The type and quality of antenna used.

•The height of the antenna's mount- ing location — the higher the antenna, the greater the signal's range

•The surrounding terrain — moun- tains and tall buildings limit the range.

•Weather conditions.

•The number of nearby CBs operat- ing on the same channel.

REDUCING NOISE

The audio clarity enhancer (ACE) circuit uses compander (compressor and ex- pander) technology to improve commu- nication quality. The circuit maintains the dynamic range while increasing the signal-to-noise ratio as the gain is auto- matically controlled according to the in- put signal level. This results in a reduction in wide band noise.

The noise blanking (NB) circuit helps keep background noise to a minimum. However, strong sources of electrical noise, generated by spark plugs or the ignition of your car, or another radio, might be more than the circuit can com- pensate for.

If you suspect engine noise as a source, turn off the engine and operate the CB with the ignition set to ACC. If most or all of the noise stops, the problem is in ve- hicle's ignition or electrical system.

The following few hints can help you re- duce or eliminate such noise.

•Replace old ignition wires with new,

high-voltage, noise-suppression wires.

•Install noise suppressors on your spark plugs, or install new spark plugs that have built-in suppressors.

•Be sure that the black wire ground connection is securely attached to either your vehicle’s battery's nega- tive (GND) terminal or to a good electrical chassis ground.

If problems persist, check your alterna- tor or generator, voltage regulator, and any stand-alone gauges. Noise from these sources can be reduced or elimi- nated using bypass capacitors at vari- ous output voltage points.

Your local RadioShack store has a wide selection of noise-suppression accesso- ries.

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Radio Shack TRC-446 owner manual Maximum Range, Reducing Noise
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TRC-446 specifications

The Radio Shack TRC-446 is a classic handheld CB (Citizens Band) radio, well-regarded in the realm of two-way communication devices. Released in the 1980s, it has become a sought-after collector's item due to its impressive features, build quality, and ease of use.

One of the defining characteristics of the TRC-446 is its compact and portable design. Weighing less than many of its contemporaries, it fits comfortably in the hand and is lightweight enough for prolonged use. This makes it an excellent choice for outdoor enthusiasts, truck drivers, and hobbyists alike. Its robust construction ensures that it can withstand the rigors of daily use.

In terms of technology, the TRC-446 operates on the standard 40 channels designated for CB radios in the United States, allowing users to communicate over short distances. It incorporates AM modulation, which was the primary mode of communication for CB radios, ensuring compatibility with a wide range of other devices. The operating range can reach several miles, depending on the terrain, making it ideal for both urban and rural communication.

The user interface is designed for simplicity, featuring a clear display with channel indicators, an easy-to-access volume control, and a squelch knob to eliminate background noise. The push-to-talk button is conveniently placed, providing seamless access during conversations. Additionally, the TRC-446 comes equipped with a built-in microphone, making voice transmission effortless.

Another noteworthy feature is the external antenna jack, which allows for improved communication range. Users can connect various antennas, enhancing their ability to send and receive signals in challenging environments.

The TRC-446 also supports compatibility with additional accessories, such as handsets and speakers, allowing for a more customizable communication experience. The battery life is decent for a handheld device, with options for both rechargeable and disposable batteries, making it versatile for different use cases.

In conclusion, the Radio Shack TRC-446 represents a significant piece of communication technology from the late 20th century. With its reliable performance, user-friendly design, and compatibility with a range of accessories, it remains a cherished model among CB radio enthusiasts. Whether for nostalgia or practical use, the TRC-446 stands out as a testament to the enduring appeal of two-way radio communication.
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