21-1598.fm Page 1 Thursday, August 5, 1999 10:52 AM Cat. No. 21-1598 OWNER’S MANUAL Please read before using this equipment.
1-1598.fm Page 2 Thursday, August 5, 1999 10:52 AM FEATURES Your RadioShack TRC-498 40Channel CB Mobile Transceiver is a breakthrough in CB design technology. It includes a DSP (Digital Signal Processor) circuit for improved audio quality, which reduces background noise and virtually eliminates the whines and whistles commonly heard on crowded CB frequencies. Emergency Channel Switch — lets you quickly switch to Channel 9 so you can monitor or report emergency situations.
21-1598.fm Page 3 Thursday, August 5, 1999 10:52 AM Note: To use this CB, you must connect a mobile or base station antenna. Your local RadioShack store has a wide variety of antennas. For more information, see “Connecting an Antenna” on Page 6. We recommend you record your CB’s serial number here. The number is on the CB’s back panel. Serial Number _________________ FCC INFORMATION The Federal Communications Commission (FCC) does not require you to have a license to operate this CB radio.
21-1598.fm Page 4 Thursday, August 5, 1999 10:52 AM CONTENTS Installation ............................................................................................................ Attaching the Microphone Holder .................................................................... Mounting the Transceiver ................................................................................ Connecting an Antenna ...................................................................................
21-1598.fm Page 5 Thursday, August 5, 1999 10:52 AM INSTALLATION ATTACHING THE MICROPHONE HOLDER You can connect the microphone holder to either side of the transceiver or to another location in your vehicle. To attach the holder to either side of the transceiver, secure the holder to the side using the supplied screws and lock washers. Note: If you cannot reach behind the mounting surface to attach the nuts on the machine screws, use the supplied 3 mm plain washers and self-tapping screws.
21-1598.fm Page 6 Thursday, August 5, 1999 10:52 AM Caution: If you use the CB in a vehicle, mount it securely to avoid damage to the CB or vehicle or injury to anyone in the vehicle during sudden starts or stops. Follow these steps to mount the CB using the supplied hardware. nuts on the bolts, use the supplied 6 mm self-tapping screws and plain washers to secure the bracket. 4. Attach the CB to the mounting bracket using the supplied rubber washers and mounting knobs. 1.
21-1598.fm Page 7 Thursday, August 5, 1999 10:52 AM Once you choose an antenna, follow its mounting instructions. Then route the cable to the transceiver and connect the cable to the ANT jack on the back of the transceiver. CONNECTING THE MICROPHONE 1. Press the tab on the side of the supplied microphone’s plug and insert the plug into the microphone jack on the side of the transceiver. Be sure the tab is aligned with the jack’s notch.
21-1598.fm Page 8 Thursday, August 5, 1999 10:52 AM CONNECTING OPTIONAL SPEAKERS You can connect your transceiver to an external CB speaker and/or a PA (public address) speaker. Note: When you connect an external or PA speaker, the CB’s internal speaker disconnects. Using an External CB Speaker The external speaker you use with the transceiver should have an impedance of 8 ohms and be able to handle 3 to 10 watts of power, such as RadioShack Cat. No. 21-549. The speaker cable must have a 1/8-inch plug.
21-1598.fm Page 9 Thursday, August 5, 1999 10:52 AM USING VEHICLE BATTERY POWER Follow these steps to connect the transceiver to vehicle battery power. USING THE TRANSCEIVER AS A BASE STATION Although this transceiver is designed mainly for mobile use, you can also use it as a base station with an AC power source. For base station installation, you need these items: Red Wire to Switched Accessory Terminal Black Wire to Ground 1.
21-1598.fm Page 10 Thursday, August 5, 1999 10:52 AM Follow these steps to install the CB as a base station. 3. Connect the transceiver’s black power wire to the negative (–) terminal on the DC power supply. 4. Connect the transceiver’s red wire (with the in-line fuse) to the positive (+) terminal on the DC power supply. Antenna Black Wire to Negative Terminal of DC Power Supply Red Wire to Positive Terminal of DC Power Supply 1. Mount the base station antenna as described in its owner’s manual.
21-1598.fm Page 11 Thursday, August 5, 1999 10:52 AM OPERATION Caution: To prevent damage to the CB, be sure you connect an antenna and the microphone before you use the CB. Before you use your CB, you should know how to use it effectively and courteously. “Operational Hints” contains information that will help you get more enjoyment from your CB. 5. Set OUT/CH9 to OUT to select a channel other than Channel 9 (the emergency channel). RECEIVING TRANSMISSIONS AND ADJUSTING SQUELCH 1. Set CB/PA to CB. 2.
21-1598.fm Page 12 Thursday, August 5, 1999 10:52 AM Note: To receive very weak signals, turn SQUELCH counterclockwise. You hear noise between transmissions, but you also hear weak transmissions (those not strong enough to break through a higher squelch setting). 9. When the transceiver receives a signal, the RX SIGNAL indicators light. If the received signal is distorted, decrease the overall signal level by rotating RF GAIN counterclockwise.
21-1598.fm Page 13 Thursday, August 5, 1999 10:52 AM • The MOD (modulation) light flickers as you speak. If the indicator lights continuously, you are speaking too loudly. If it lights dimly, you might be speaking too softly. MOD 3. To turn off the CB, turn VOLUME counterclockwise until you hear it click. The display and indicators turn off.
21-1598.fm Page 14 Thursday, August 5, 1999 10:52 AM USING THE PA AMPLIFIER Your CB has a built-in PA (public address) amplifier. With an optional PA speaker, you can turn your radio into a mobile public address system. Follow these steps to use the PA amplifier after you connect an external PA speaker (see “Connecting a PA Speaker” on Page 8). 1. Turn on the transceiver. Then set CB/PA to PA. PA appears on the display. CB PA 2. To transmit, press the talk button on the microphone.
21-1598.fm Page 15 Thursday, August 5, 1999 10:52 AM OPERATIONAL HINTS Like most activities, CB radio has its customs and courtesies. The following tips will help you get the most enjoyment from your CB. COMMON USES FOR A CB Personal Uses • Keep in touch with home while driving to work, to the store, or to a social activity. Let your family know you are tied up in traffic or that you will stop by the store on the way home.
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21-1598.fm Page 17 Thursday, August 5, 1999 10:52 AM USING COMMON 10-CODES Citizen’s band operators and CB radio users have largely adopted the 10-codes for standard questions and answers. These codes permit faster communication and better intelligibility in noisy areas. This table lists codes adopted by the Associated Public-Safety Communications Officers (APCO). Code Meaning Code Meaning 10-1 Your signal is bad. 10-17 En route. 10-2 Your signal is good. 10-18 Urgent. 10-3 Stop transmitting.
21-1598.fm Page 18 Thursday, August 5, 1999 10:52 AM TROUBLESHOOTING If at any time you suspect that your CB is not working as it should, refer to the following chart to see if you can eliminate the problem. If these solutions do not solve the problem, do not attempt repairs or adjustment yourself. The CB should be serviced only by a qualified radio technician. If you still have problems, take your CB to a local RadioShack store for assistance. Symptom Solution Turn transceiver power on.
21-1598.fm Page 19 Thursday, August 5, 1999 10:52 AM Symptom Solution Power connected? Secure connections. Radio does not work at all. Microphone connected? Secure connections. Fuse needs replacing? Replace with identical fuse. See “Replacing the Fuse” on Page 22. Set CB/PA to CB. Cannot select a channel. Set OUT/CH9 to OUT. Talk button fully pressed in? Press completely. Connect a PA speaker. Secure connections. PA does not work. Set CB/PA to PA. Adjust VOLUME. Adjust RF GAIN. Sound is distorted.
21-1598.fm Page 20 Thursday, August 5, 1999 10:52 AM REDUCING NOISE Because your CB is exceptionally quiet, any noise you hear is probably from an external source in your vehicle such as the alternator, another radio or spark plugs. The transceiver uses an ANL (Automatic Noise Limiter) circuit and a DSP (Digital Sound Processor) circuit to reduce noise. However, if possible, try to eliminate the noise by finding its source.
-1598.fm Page 21 Thursday, August 5, 1999 10:52 AM CARE AND MAINTENANCE Your RadioShack TRC-498 40-Channel CB Mobile Transceiver is an example of superior design and craftsmanship. The following suggestions will help you care for your CB so you can enjoy it for years. Keep the CB dry. If it gets wet, wipe it dry immediately. Liquids can contain minerals that can corrode electronic circuits. Handle the CB gently and carefully.
21-1598.fm Page 22 Thursday, August 5, 1999 10:52 AM REPLACING THE FUSE The TRC-498’s 2-amp in-line fuse helps protect your CB from power surges and short circuits. When replacement is required, use a 2-amp, slow-blow glass fuse, such as Cat. No. 270-1023. Follow these steps to replace the fuse. 1. Make sure the power source and CB are both off. 2. Hold the fuse holder by both ends, push the ends together, twist one end counterclockwise, then pull them apart. 3.
21-1598.fm Page 23 Thursday, August 5, 1999 10:52 AM SPECIFICATIONS RECEIVER Frequency Coverage ................All 40 CB Channels (Class D) 26.965–27.405 MHz Sensitivity for 10dB S/N ................................................................................ 0.5 mV Squelch Sensitivity at Tight ........................................................................1000 mV Overall Audio Fidelity for 450–2500 Hz ..........................................................
21-1598.fm Page 24 Thursday, August 5, 1999 10:52 AM RadioShack Limited Warranty This product is warranted against defects for 90 days from date of purchase from RadioShack company-owned stores and authorized RadioShack franchisees and dealers. Within this period, we will repair it without charge for parts and labor. Simply bring your RadioShack sales slip as proof of purchase date to any RadioShack store. Warranty does not cover transportation costs.
