Owner's Manual AMATEUR 10 METER MOBILE RADIO 1 GTL DX 50 Nothing comes close to a Cobra® Printed in Philippines Part No. 480-216-P Version A English Introduction Our Thanks to You and FCC License Required · Our Thanks to You Thank you for purchasing a Cobra amateur mobile radio. Properly used, this Cobra product will give you many years of reliable service. FCC License Required The United States Federal Communications Commission (FCC) requires that users of the frequencies on which this radio operates be licensed. See page 16 for licensing and other FCC information. · © 2005 Cobra® Electronics Corporation 6500 West Cortland Street Chicago, Illinois 60707 USA www.cobra.com A1 English Introduction Controls and Indicators · S/RF / SWR / CAL RF Power Hi / Low PA / AM / FM Analog Meter Band A/B/C/D +10 kHz / Off RX / TX Indicator NB/ANL / ANL / Off Dual 7 Segment Frequency Display Introduction Microphone and Features · Controls and Indicators Microphone Press-To-Talk Button (PTT) WARNING RISK OF ELECTRIC SHOCK. DO NOT OPEN. DO NOT REMOVE COVER OR BACK. NO USER SERVICEABLE PARTS INSIDE. REFER TO SERVICING TO QUALIFIED SERVICE PERSONNEL. Features -341 Operating Frequencies Allows operation on all available frequencies. 15 Watts Output Power Provides maximum power on AM and FM. Dual Finals Provides steady output power. Dual Power Allows operation on Low and High power. SWR Calibration Allows measurement and adjustment of the antenna system. Antenna Warning Indicator Illuminates when the antenna system needs repair or adjustment. Echo Control Allows control of echo effect. -Talk-Back Control Allows user to monitor feedback of output signal. Large Analog Meter Provides high visibility of status meter. NightWatchTM Panel Electroluminescent illumination of front panel for night operation. 4 Pin Front Mic Connector Allows convenient installation in-dash. Frequency Counter Jack Allows connection of a 6-digit frequency counter. Mic Gain Control Allows increased voice clarity by dynamically boosting microphone. · Microphone Connector Off / On / Volume (center knob) Squelch (outer ring) Public Address (PA) Speaker Connector External Speaker Connector Microphone Gain (center knob) RF Gain (outer ring) Echo (center knob) Talk Back (outer ring) -Frequency Selector Antenna Warning Indicator -- --- -- -- Dim (center knob) SWR CAL (outer ring) Antenna Connector -- -- -- -- -- This Cobra radio has a superior receiver that includes an RF gain control and noise blanker circuitry as well as an automatic noise limiter. The receiver also features increased protection against cross modulation and strong adjacent signals. To obtain maximum performance, please read carefully the descriptions and operating instructions in this manual. A3 English Power Cord Connector A2 English Frequency Counter Connector Introduction Contents Product Features Introduction Our Thanks to You . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A1 FCC License Required . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A1 Controls and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A2 Microphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A3 Your Mobile Radio Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Included in this Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Installation and Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Microphone . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Operating to Receive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Operating to Transmit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Government Regulatory Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16 Alternate Microphones and Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 ARRL Q Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20 Warranty Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Trademark Acknowledgement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Customer Assistance Product Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Order Form and Optional Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Nothing comes close to a Cobra® 1 Your Mobile Radio Specifications · 28.0 to 29.7 MHz Phase Lock Loop (PLL) synthesizer 0.005% -22°F to 122°F (-6°C to + 50°C) 50 ohms Standard SO 239 type Plug-in dynamic with Press-To-Talk switch and coiled cord 13.8 V DC nominal, 15.9 V max., 10.0 V min. (positive or negative ground) Transmit: 3.0 A Receive (squelched): 0.5 A Receive (maximum audio output): 1.2 A 23/8" (H) x 77/8" (W) x 93/4" (D) [6 cm (H) x 20 cm (W) x 24.8 cm (D)] 4.8 lbs. Illuminated ­ indicates relative output power, received signal strength, and SWR 4 watts Your Mobile Radio Specifications · AM: 0.5 µV for 10 dB S/N FM: 0.25 µV for 12 dB S/N 300 to 3,000 Hz 45 dB 75 dB 65 dB 40 dB ­ adjustable for optimum signal reception Adjustable ­ threshold less than 0.5 µV Switchable Switchable Meter shows relative signal strength. Receive LED glows green when receiving a signal. Specifications General Frequency Range Frequency Control Frequency Stability Operating Temperature Range Antenna Impedance Antenna Connector Microphone Input Voltage Current Drain Specifications Receiver Sensitivity Audio Frequency Response Maximum Signal to Noise Ratio Image Rejection Adjacent Channel Rejection RF Gain Control (AGC) Squelch Automatic Noise Limiter (ANL) Noise Blanker (NB) Receive Indicators Size Weight Meter (3-in-1) Built-in Speaker Transmitter Power Output Frequency Response Frequency Tolerance Transmit Distortion Spurious Harmonic Emission Output Indicators Antenna Warning LED PA System Power Output Speaker for PA (Not Supplied) External Speaker Power Output External Speaker (Not Supplied) 4 watts into external speaker 8 ohms 4 watts into PA speaker 8 ohms Low ­ 4 watts; High ­ 15 watts 300 to 3,000 Hz 500 Hz 2% -65 dB Meter shows relative RF output power and SWR. Transmit LED glows red when transmitter is in operation. Glows red when SWR is greater than 3.0. (Specifications subject to change without notice) 2 English Nothing comes close to a Cobra® 3 Your Mobile Radio Included in this Package · Your Mobile Radio Installation and Connection · Included in this Package You should find all of the following items in the package with your radio. Installation and Connection Refer to the illustration on page A3 for connection points on the back of the unit while installing your radio. -- Transceiver Universal Mounting Bracket Location Plan the location of the transceiver and microphone brackets before starting the installation. Select a location that is convenient for operation and does not interfere with the driver or passengers in the vehicle. In automobiles, the transceiver is usually mounted below the dash panel, with the microphone bracket beside it. -Mounting Your mobile radio is supplied with a universal mounting bracket. When mounting the bracket and radio to your car, make sure it is mechanically strong. Also provide a good electrical connection to the chassis of the vehicle. Proceed as follows to mount the transceiver: -Mount the Transceiver 1. After you have determined the most convenient location in your vehicle, hold the mobile radio with the mounting bracket in the exact location desired. If nothing will interfere with mounting it in the desired position, remove the thumbscrews and use the mounting bracket as a template to mark the holes for the mounting screws. Before drilling the holes, make sure nothing behind the surface will be damaged or interfere with the installation. 2. Connect the antenna cable plug to the standard receptacle (ANT) on the rear panel. Most antennas are terminated with a type PL-259 plug and mate with the receptacle. 3. Connect the red DC power input wire (with the fuse) to +13.8 V DC. This wire extends from the rear panel. Connect directly to positive terminal (red) of vehicle's battery. Operating Instructions Controls and Indicators · S/RF / SWR / CAL RF Power Hi / Low PA / AM / FM Analog Meter Band A/B/C/D +10 kHz / Off RX / TX Indicator NB/ANL / ANL / Off Dual 7 Segment Frequency Display Microphone Introduction Controls and Indicators Microphone Connector Off / On / Volume (center knob) Squelch (outer ring) Public Address (PA) Speaker Connector External Speaker Connector Microphone Gain (center knob) RF Gain (outer ring) Echo (center knob) Talk Back (outer ring) Frequency Selector Antenna Warning Indicator Dim (center knob) SWR CAL (outer ring) Antenna Connector Power Cord Connector A2 English Frequency Counter Connector 4. Connect the black lead to -13.8 V DC. This is usually the chassis of the car. Any convenient location with good electrical contact (remove paint) may be used. Microphone Bracket 5. Mount the microphone bracket on either side of the transceiver, using the two screws supplied. When mounting in an automobile, place the bracket under the dash so the microphone is readily accessible. 6. Attach the microphone cable to the connector on the face of the transceiver. NOTE If power cables need to be shorter, we recommend attaching a 10 amp fuse to positive cable (red) at least six inches from vehicle's battery. 4 English Nothing comes close to a Cobra® 5 Your Mobile Radio Installation and Connection · Your Mobile Radio Installation and Connection · Installation and Connection Ignition Noise Interference Use of a mobile receiver at low signal levels is normally limited by the presence of electrical noise. The primary source of noise in automobile installations is from the generator and ignition system in the vehicle. Under most operating conditions, when signal level is adequate, the background noise does not present a serious problem. However, when extremely low-level signals are being received, the transceiver may be operated with vehicle engine turned off. The unit requires very little current and therefore will not significantly discharge the vehicle battery. Even though your mobile radio has ANL and NB controls, in some installations ignition interference may be high enough to make good communications impossible. The electrical noise may come from several sources. Many possibilities exist and variations between vehicles require different solutions to reduce the noise. Consult your Cobra dealer or a two-way radio technician for help in locating and correcting the source of severe noise. --- Installation and Connection Tuning the Antenna for Optimum SWR Because such a wide variety of base and mobile antennas are available, this section will concern itself only with the usual types of mobile adjustable antennas. Antenna length is directly related to signal frequency. Therefore, it must be tuned to resonate optimally throughout the frequency range of the transceiver. Lower frequencies require a longer antenna than higher frequencies. Due to the various methods of adjusting antennas for proper SWR, we have chosen what we think is the optimum method: A. Antennas with adjustable screws (setscrews). 1. Start with the antenna extended and tighten the setscrew lightly enough so that the antenna can be lightly tapped with your finger for easy adjustment. 2. Set your mobile radio to your desired operating frequency or the center of the range of frequencies you plan to use. Press the PTT (Press-To-Talk) switch, and tap the antenna (making it shorter). The SWR meter will show a lower reading each time the antenna is tapped. By continuing to shorten the antenna, you will notice the SWR ...