Cobra 148 GTL 148GTLE_Eng-Spa - Page 6

Section III Installation (Continued) D. Try a different location on your car (keeping in mind the radiation pattern you wish). E. Is the antenna perfectly vertical? F. Try a different location in your neighborhood. Stay away from large metal objects when adjusting (metal telephone or light posts, fences, etc.). NOTE The COBRA 148GTL will operate into an SWR of 2 to 1 indefinitely and sustain an SWR of 20:1 for a maximum of 5 minutes at rated operating conditions. EXTERNAL SPEAKER The external speaker jack (EXT SPK) on the rear panel is used for remote receiver monitoring. The external speaker should have 8 ohms impedance and be able to handle at least 4 watts. When the external speaker is plugged in, the internal speaker is disconnected. PUBLIC ADDRESS To use the transceiver as a public address system connect an external 8 ohm speaker (4 watts minimum) to the PA SPK jack located on the rear panel. Direct speaker away from the microphone to prevent acoustic feedback. Physical separation or isolation of the microphone and speaker is important when operating the PA at high output levels. Section IV Operation CONTROLS AND INDICATORS There are thirteen controls and three indicators on the front panel of your COBRA 148GTL. A. CONTROL FUNCTIONS 1. OFF/ON/VOLUME (inner dual concentric). Turn clockwise to apply power to the unit and to set the desired listening level. During normal CB operation, the Volume control is used to adjust the output level obtained either at the transceiver speaker or the external speaker, if used. 2. SQUELCH (outer dual concentric). This control is used to cut off or eliminate receiver background noise in the absence of an incoming signal. For maximum receiver sensitivity it is desired that the control 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 clockwise setting. 3. RF GAIN CONTROL (inner dual concentric). Used to reduce the gain of the RF amplifier under strong signal conditions. 8 9