Cobra Electronics 150GTLDX owner manual Installation and Connection Operation, Controls

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Installation and Connection

and Operation

Your Mobile Radio

Installation and Connection

If you are having difficulties in adjusting your antenna, check the following:

1.All doors must be closed when adjusting the antenna.

2.Make sure the antenna base is grounded.

3.Check your coaxial cable routing — it may be pinched where routed into the car.

4.Try a different location on your car — keeping in mind the radiation pattern you want.

5.Make sure the antenna is perfectly vertical.

6.Try a different location in your neighborhood. Stay away from large metal objects (metal utility or light poles, fences, etc.) when adjusting.

NOTE

The radio will operate into a SWR of 2 to 1 indefinitely and sustain an SWR of 20 to 1 for a maximum of 5 minutes at rated operating conditions.

- -4External Speaker

The external speaker jack (EXT) 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 four watts. When the external speaker is plugged in, the internal speaker is disabled.

- -4Public Address

To use the transceiver as a public address system, connect an external 8 ohm speaker that is able to handle at least four watts to the PA jack on the rear panel. Direct the 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.

Operation

There are 15 controls and 4 indicators on the front panel of your mobile radio. These are shown in the illustration on page A2 which may be folded out for reference when using this section.

Controls

Your Mobile Radio

Controls

- -

 

4Off / On / Volume

 

Turn clockwise to apply power to the unit and to set the desired listening level.

 

During normal operation, the volume control is used to adjust the output level

 

obtained either at the transceiver speaker or the external speaker, if used.

 

- -

 

4Squelch

 

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

 

that a signal must overcome in order to be heard. Only strong signals will be heard

 

at the maximum clockwise setting.

 

- -4Microphone Gain

Adjusts the microphone gain in the transmit and PA modes. This controls the gain to the extent that full talk power is available several inches away from the microphone. In the Public Address (PA) mode, the control functions as the volume control for the PA speaker.

- -4RF Gain

Used to reduce the gain of the RF amplifier when receiving very strong signals.

- -4PA / AM / FM

Selects the mode of operation. In the AM and FM positions, the PA function is disabled and the unit will transmit and receive on the internal speaker. In the PA mode, incoming transmissions will be heard through the PA speaker. This allows you to monitor messages while outside of your vehicle. To use the PA feature, a speaker having a voice coil impedance of 8 ohms and a power handling capability of at least four watts should be used. This speaker must be plugged into the PA SPKR jack at the rear of the transceiver. If the public address feature is to be used primarily for outdoor applications, the use

of a weatherproof horn-type public address speaker is recommended. The durability of this type speaker plus the inherent efficiency of such a speaker will provide more than adequate results when combined with the high audio output level available from your radio. With the PA speaker connected as outlined previously, be sure that there is physical separation between the microphone and the speaker itself. If the speaker is located too close to the microphone, acoustic feedback will result when the public address system is operated at high volume. A directional-type outdoor speaker reduces the amount

of isolation required. Some experimentation will determine the minimum amount of isolation required for a given sound level from the public address system.

NOTE

The microphone gain knob also controls the PA volume when in PA mode.

 

8 English

Nothing comes close to a Cobra® 9

 

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Contents GTL DX FCC License Required Our Thanks to You FCC License RequiredOur Thanks to You Controls and Indicators Microphone and Features Controls and IndicatorsFeatures MicrophoneContenProductsFeatures WarrantyIntroduction Your Mobile RadioSpecifications SpecificationsInstallation and Connection Installation and ConnectionIncluded in this Package Included in this Package4Tuning the Antenna for Optimum SWR Antennas with adjustable screws setscrews4Ignition Noise Interference 4AntennaInstallation and Connection Operation ControlsOperation Controls4Dim 4NB/ANL / ANL / Off4Echo 4Talk BackFrequency FrequencyIndicators and Microphone Operating to Receive and Transmit IndicatorsOperating to Receive Operating to TransmitMaintenance and Government Regulatory Information Alternate Microphones InstallationMaintenance Alternate Microphones and InstallationAlternate Microphones and Installation Arrl Q Signals Arrl Q SignalsWarranty and Trademark Acknowledgement Product ServiceLimited Two-Year Warranty Product ServiceAccessories Order Form Optional AccessoriesAccessories Optional AccessoriesCobra line of quality products includes