Cobra Electronics Cobra 148 GTL - Manual (Page 3)

RECEIVER
Sensitivity SSB: 0.25 µV for 10dB (S+N)/N at greater
than 1/2-watt of audio output.
AM: 0.5
µV for 10 dB (S+N)/ at greater
than 1/2-watt of audio output.
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.
Adjacent-Channel Rejection 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.
Built-in Speaker 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)
Section II Specifications (Cont.)
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Section II Specifications
GENERAL
Channels 40 AM, 40LSB, 40 USB.
Frequency Range 26.965 to 27.405 MHz.
Frequency Control Phase Lock Loop (PLL) synthesizer.
Frequency Tolerance 0.005%
Frequency Stability 0.001%
Operating Temperature Range -30° C to + 50° C
Microphone Plug-in dynamic; with push-to-talk
switch and coiled cord.
Input Voltage 13.8V DC nominal, 15.9V max., 11.7V
min. (positive or negative ground).
Current Drain Transmit: AM full mod., 2.2A. SSB 12
watts PEP output, 2A.
Receive: Squelched, 0.25A
Maximum audio output, 0.6A.
Size 2 3/8”(H) x 7 7/8”(W) x 9 1/4”(D).
Weight 5 lbs.
Antenna Conductor UHF, S0239.
Semiconductors 3 field effect transistors, 45 transistors,
63 diodes, 6 integrated circuits, 1 two
color light emitting diode.
Meter (3-in-1) Illuminated; indicates relative output
power, received signal strength,
and SWR.
TRANSMITTER
Power Output AM, 4 watts.
SSB, 12 watts, PEP.
Modulation High-and low-level Class B, Amplitude
Modulation.
Intermodulation Distortion SSB: 3rd order, more than -25 dB.
5th order, more than -35 dB.
SSB Carrier Suppression 55 dB.
Unwanted Sideband 50 dB.
Frequency Response AM and SSB; 300 to 2500 Hz.
Output Impedance 50 ohms, unbalanced
Output Indicators Meter shows relative RF output power
and SWR. Transmit LED glows red when
transmitter is in operation.
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