OPERATING INSTRUCTIONS FOR YOUR 40 CHANNEL SOLID STATE CITIZENS BAND SSB/AM TWO-WAY RADIO BASE STATION With Seven Weather Channels and NOAA Emergency Alert Tone Model 2010 GTL WX How To Use Your Cobra Contents ® SOLID STATE CITIZENS BAND SSB/AM 2-WAY RADIO BASE STATION Model 2010 GTL WX Page The CB Story .................................................................................... 1 Section I: Introduction ..................................................................... 2 Section II: Specifications ............................................................. 3, 4 Section III: Installation .................................................................... 5 Section IV: Operation ............................................................... 6 - 17 Control Functions ................................................................. 6, 7, 8 Indicator Functions ....................................................................... 9 Operating Procedure to Receive ................................................. 10 Operating Procedure to Transmit ................................................ 10 Operating Procedure to Receive Weather Band .................... 10, 11 Frequency Counter/LCD Digital Clock ........................................ 11 Receiving SSB Signals ........................................................... 13, 13 Section V: Maintenance and Adjustment ....................................... 14 FCC Warning .............................................................................. 14 Section VI: Appendix ......................................................... 15, 16, 17 Ten Code .................................................................................... 15 A Few Rules That Should Be Obeyed ......................................... 16 How Your CB Can Serve You ..................................................... 16 Use Channel 9 for Emergency Messages Only ............................ 17 Alternate Microphones and Installation .......................... 18, 19, 20 Warranty Service Instructions ..................................................... 21 Limited One Year Warranty ........................................................ 22 Cobra CB Radio 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 communications 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." Replacement or substitution of transistors, regular diodes or other parts of a unique nature, with parts other than those recommended by Cobra Electronics, 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. Citizens Band (CB) Radio operators are no longer required to obtain an FCC license to operate their CB equipment or provide station identification. Nevertheless, an operator of a CB radio station is still required to comply with the communications act and with the rules of CB Radio Operation. What Is Weather Radio? NOAA WEATHER RADIO (NWR) is a service of the National Oceanic and Atmospheric Administration (NOAA), of the U.S. Department of Commerce. It provides continuous, around-the-clock broadcasts of the latest weather information directly from National Weather Service Offices. The broadcasts are tailored to the weatherinformation needs of people within the receiving area. For example, coastal and Great Lakes' stations provide specialized weather information for area boaters, fishermen and others engaged in marine activities, as well as general weather information for the public-at-large. Three hundred eighty (380) NWR stations are in operation by the U.S. Government in addition to several NWR stations that are maintained by private interest groups. Under a January 1975 White House policy statement, NOAA Weather Radio was designated as the sole Government operated radio system to provide direct warnings into private homes for both natural disasters and nuclear attack. The capability is to supplement warnings by sirens and by commercial radio and television. NWR Frequencies and Transmission Characteristics NWR broadcasts have been allocated seven frequencies within the VHF radio spectrum reserved for Government use. Assigned frequencies are: 162.400 MHz 162.425 MHz 162.450 MHz 162.475 MHz 162.500 MHz 162.525 MHz 162.550 MHz 1 Section I Introduction FREQUENCY RANGE The COBRA 2010 GTL WX transceiver represents one of the most advanced AM base station radios used as a Class D station in the Citizens Radio Service. This unit features advanced Phase Lock Loop (PLL) circuitry providing complete coverage of all 40 channels as shown below. CB Channel 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 Channel Freq. CB Channel Freq. in MHz Channel in MHz 26.965 26.975 26.985 27.005 27.015 27.025 27.035 27.055 27.065 27.075 27.085 27.105 27.115 27.125 27.135 27.155 27.165 27.175 27.185 27.205 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 27.215 27.225 27.255 27.235 27.245 27.265 27.275 27.285 27.295 27.305 27.315 27.325 27.335 27.345 27.355 27.365 27.375 27.385 27.395 27.405 Weather Channel 1 2 3 4 5 6 7 Weather Freq. in MHz 162.550 162.400 162.475 162.425 162.450 162.500 162.525 The COBRA 2010 GTL WX has a vastly superior receiver which includes noise blanker circuitry and a switchable automatic noise limiter. The receiver also features increased protection against cross modulation and strong adjacent channel signals. To obtain maximum performance please read carefully the descriptions and operating instructions in this manual. Fill out below;keep for your records. Serial No. Date of Purchase Dealer Name Keep this manual for detailed information about your Cobra CB radio. SAVE YOUR SALES RECEIPT, CARTON AND PACKING FOR POSSIBLE FUTURE USE. 2 Section II Specifications GENERAL Channels Frequency Range Frequency Control Frequency Tolerance Operating Temperature Range Microphone Power Source 40. 26.965 to 27.405 MHz. Phase Lock Loop (PLL) synthesizer. ±130 Hz Typical. -30° C to + 50° C. Plug-in type; 600 dynamic. 120V AC nominal. 13.8V DC nominal. (Positive or negative ground). Transmit: AM full mod., 65 watts. SSB 70 watts. Receive: Squelched, 30 watts. Full audio, 40 watts. Transmit: AM and SSB, 2.2A DC (nominal). Receive: Full audio output, 1.1A DC 5"(H) x 15"(W) x 4 7/16"(D). 19 1/2 lbs. (Including speaker). UHF, S0239. 12 integrated circuits, 3 FETs, 58 transistors, 79 diodes, 1 LCD. Illuminated; indicates relative power output, received signal strength. Illuminated; indicates standing wave ratio and level of modulation. AM, 4 watts. SSB, 12 watts, PEP. High-and low-level Class B, Amplitude Modulation. SSB: 3rd order, more than -25 dB. 5th order, more than -35 dB. 55 dB. 50 dB. AM and SSB; 300 to 2500 Hz. 50 ohms, unbalanced Meter shows relative RF output power and SWR. RX/TX USB/LSB AM ANT. icons on LCD, channel frequency and clock. Power Consumption Current Drain (13.8V DC) Size Weight Antenna Conductor Semiconductors Meter 1 Meter 2 TRANSMITTER Power Output Modulation Intermodulation Distortion SSB Carrier Suppression Unwanted Sideband Frequency Response Output Impedance Output Indicators 3 Section II Specifications (Cont.) RECEIVER Sensitivity SSB: 0.25 µV for 10dB (S+N)/N at greater than 1/2-watt of audio output. AM: 0.5µV for 10 dB (S+N)/ at greater than 1/2-watt of audio output. AM: 6dB @ 3 KHz, 50 dB @ 9 KHz. SSB: 6 dB @ 1.1 KHz, 60 dB @ 2.3 KHz. More than 65 dB. AM: 7.8 MHz 1st IF, 455 KHz 2nd IF. SSB: 7.8 MHz. 60 dB AM & 70 dB SSB. 40 dB adjustable for optimum signal reception. Less than 10 dB change in audio output for inputs from 10 to 100,000 microvolts. Adjustable; threshold less than 0.25 µV. Switchable. RF type, effective on AM and SSB. ±1.5 KHz. 4 watts into 8 ohms. 300 to 2500 Hz. 8 ohms, round. 8 ohms; disables internal speaker when connected. 24 hr. time. Displays transmit and receive frequency. Single Conversion, Superhet 455Hz IF. FM; ± 5 KHz Deviation. Less than 1µV for 12dB Sinad. 162.400 to 162.550 MHz. 7; 25KHz Spacing. Crystal. Phase Lock Loop; 1050Hz. 4 watts. Selectivity Image Rejection IF Frequency Adjacent-Channel Rejection AM and SSB RF Gain Control Automatic Gain Control (AGC) Squelch ANL Noise Blanker Voice Lock Range Audio Output Power Frequency Response Built-in Speaker External Speaker (Not Supplied) CLOCK/COUNTER Clock Counter WEATHER (WX) RECEIVER Type Modulation Sensitivity Frequency Range Channels Frequency Control WX Emergency Warning Audio Output Power (SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE) 4 Section III Installation LOCATION Prior to beginning operation of the transceiver, a basic installation must be prepared. Installation of the transceiver itself is a rather simple procedure. In selecting the location for the unit, two basic factors must be considered: 1. Access to a 120V, 60 Hz power source. 2. The location must be convenient for running the antenna lead-in cable if outside antenna installation is proposed. BASE STATION ANTENNA Since the maximum allowable power output of the transmitter is limited by the FCC, the antenna is the most important factor affecting transmission distance. Only a properly matched antenna system will allow maximum power transfer from the 50ohm transmission line to the radiating element. The recommended method of antenna tuning is to use the built-in SWR meter to adjust the antenna tuning for minimum reflected power on channel 21. The radio may be used with any type of 50-ohm base station antenna. A ground plane vertical antenna will provide the most uniform horizontal coverage. This type of antenna is best suited for communication with a mobile unit. For point-to-point operation where both stations are fixed, a directional beam will usually increase communicating range since this type of antenna concentrates transmitted energy in one direction. The beam antenna also allows the receiver to "listen" in only one direction thus reducing interfering signals. Antenna height is an important factor when maximum range is desired. Keep the antenna clear of surrounding structures or foliage. FCC regulations for base station antenna height are: 1. Omnidirectional antennas may not be higher than 60 feet above the ground when using a tower, mast or pole, and no higher than 20 feet above an existing structure. These are only general regulations applicable to most but not all parts of the nation. Locations near airports and some military installations are subject to different rules; therfore, it is best to contact your nearest Federal Communications Commission office for information regarding your specific area. MOBILE OPERATION/EMERGENCY POWER OPERATION It is possible to operate the Cobra 2010 GTL WX from an external 13.8V DC power supply for emergency conditions or from an automobile battery for mobile operation. We recommend using a genuine Cobra DC power cord (not supplied). The DC power cord can be purchased through your local dealer, or direct from Cobra. See CB radio Accessories on the back page of this manual. 5 Section IV Operation CONTROLS AND INDICATORS There are eighteen controls, 2 meters, 1 LCD and 1 jack on the front panel of your 2010 GTL WX. 3 11 12 17 POWER 1 PHONE 5 4 3 6 9 10 11 78 12 VOLUME 13 14 15 16 17 18 19 20 RF PWR 2 3 0 1 3 SIGNAL 5 4 9 +30 16 MIC RX TX ANT AM / SSB 2010 GTL WX HOUR USB LSB AM MIN 1.5 MOD 2 100% 3 CAL ANL CH 9 FREQ. CTR 0 10 13 DYNAMIKE BASE STA TION WITH WEATHER SWR ALERT CLOCK NB WX SQUELCH RF GAIN VOICELOCK USB 15 MIN LSB AM SWR CAL SWR CAL TUNING MOD MAX COARSE 2 4 5 7 8 6 14 9 A. CONTROL FUNCTIONS 1. POWER SWITCH. Press in to turn on radio. Press in, again, and release to turn off radio. 2. DYNAMIKE. Adjusts the microphone gain in the transmit mode. This controls the gain to the extent that full talk power is available several inches away from the microphone. 3. VOLUME. Turn clockwise to set the desired listening level. 4. SQUELCH . This control is used to cut off or eliminate receiver background noise in the absence of an incoming signal. For maximum receiver sensitivity the control should be adjusted only to the point where the receiver background noise or ambient background noise is eliminated. Turn fully counterclockwise then slowly clockwise until the receiver noise disappears. Any signal to be received must now be slightly stronger than the average received noise. Further clockwise rotation will increase the threshold level which a signal must overcome in order to be heard. Only strong signals will be heard at a maximum cloc ...