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148.GTL.ST.MANUAL 10/1/98 10:56 AM Page 7
Section II Specifications (Cont.)
RECEIVER |
|
Sensitivity | SSB: 0.25 µV for 10dB (S+N)/N at greater |
| than |
| AM: 0.5 µV for 10 dB (S+N)/ at greater |
| than |
Selectivity | AM: 6dB @ 3 KHz, 50 dB @ 9 KHz. |
| SSB: 6 dB @ 1.1 KHz, 60 dB @ 2.3 KHz. |
Image Rejection | More than 65 dB. |
IF Frequency | AM: 7.8 MHz 1st IF, 455 KHz 2nd IF. |
| SSB: 7.8 MHz. |
60 dB AM & 70 dB SSB. | |
AM and SSB RF Gain Control | 40 dB adjustable for optimum signal |
| reception. |
Automatic Gain Control (AGC) | Less than 10 dB change in audio |
| output for inputs from 10 to 100,000 microvolts. |
Squelch | Adjustable; threshold less than 0.25 µV. |
ANL | Switchable. |
Noise Blanker | RF type, effective on AM and SSB. |
Voice Lock Range | ±2.5 KHz. |
Audio Output Power | 4 watts into 8 ohms. |
Frequency Response | 300 to 2500 Hz. |
4 ohms, round. | |
External Speaker (Not Supplied) | 8 ohms; disables internal speaker |
| when connected. |
PA SYSTEM |
|
Power Output | 4 watts into external speaker. |
External Speaker for PA |
|
(Not Supplied) | 8 ohms. |
(SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE)
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Section III Installation
LOCATION
Plan the location of the transceiver and microphone bracket before starting the in- stallation. 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 usu- ally mounted below the dash panel, with the microphone bracket beside it.
MOUNTING THE CONNECTION
The COBRA 148 GTL ST 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:
1.After you have determined the most convenient location in your vehicle, hold the COBRA 148 GTL ST with mounting bracket in the exact location desired. If nothing will interfere with mounting it in the desired position, remove the mounting bolts. Before drilling the holes, make sure nothing will interfere with the installation of the mounting bolts.
2.Connect the antenna cable plug to the standard receptacle on the rear panel. Most CB antennas are terminated with a type
3.Connect the red DC power input wire (with the fuse) to +13.8V DC. This wire extends from the rear panel. In automobile installation, +13.8V DC is usually obtained from the accessory contact on the ignition switch. This prevents the set being left on accidentally when the driver leaves the car and also permits operating the unit without the engine running. Locate the accessory contact on most ignition switches by tracing the power wire from the AM broadcast receiv- er in the car.
4.Connect the black lead to
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.
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