Filter
Top Products
Specifications (cont.)
GENERAL
Channels 40
Frequency Range 26.965 to 27.405 MHz.
Frequency Control Phase Lock Loop (PLL) synthesizer.
Frequency Tolerance 0.005%.
Operating Temperature Range -30° C to + 50° C.
Microphone Plug-in dynamic.
Input Voltage 13.8VDC nom.(positive or negative ground).
Current Drain Transmit: AM full mod., 1.5A(maximum)
Receive: Squelched, 0.3A; full audio output, 1.2A
(nominal).
Size 5
3
/
4
” W x 1
3
/
4
” H x 7
1
/
2
” D .
Weight 1.2 lbs.
Antenna Connector UHF, SO-239.
Semiconductors 26 transistors, 26 diodes, 4 integrated circuits.
Meter Illuminated; indicates relative power output and
received signal strength.
TRANSMITTER
Power Output 4 watts.
Modulation AM (Amplitude Modulation).
Frequency Response 300 to 3000 Hz.
Output Impedance 50 ohms, unbalanced.
RECEIVER
Sensitivity Less than 1 µV for 10dB (S+N)/N.
Selectivity 6dB @ 7 KHz, 60 dB @ 10 KHz.
Image Rejection 80 dB, typical.
Adjacent-Channel Rejection 60 dB, typical.
IF Frequencies Double Conversion: 1st: 10.695 MHz.
2nd: 455 KHz.
Automatic Gain Control (AGC) Less than 10 dB change in audio output for inputs
from 10 to 50,000 microvolts.
RF Gain Control Adjustable for optimum signal reception.
Noise Blanker RF type.
Squelch Adjustable; threshold less than 1µV.
Audio Output Power 4 watts.
Frequency Response 300 to 3000 Hz.
Distortion Less than 7% @ 3 watts @ 1000 Hz.
Built-in Speaker 16 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 8 ohms, when PA-CB switch is in PA, the PAspeaker
(Not Supplied) also monitors the receiver; separate jack provided.
(SPECIFICATIONS SUBJECT TO CHANGE WITHOUT NOTICE)
3
FREQUENCY RANGE
The COBRA21 LTD ST transceiver represents one of the most advanced AM two-
way radios ever designed for use as a Class D station in the Citizens Radio
Service. This unit features advanced Phase Lock Loop (PLL) circuitry providing
complete coverage of all 40 channels as shown below.
Channel Channel Frequency Channel Channel Frequency
in MHz in MHz
1 26.965 21 27.215
2 26.975 22 27.225
3 26.985 23 27.255
4 27.005 24 27.235
5 27.015 25 27.245
6 27.025 26 27.265
7 27.035 27 27.275
8 27.055 28 27.285
9 27.065 29 27.295
10 27.075 30 27.305
11 27.085 31 27.315
12 27.105 32 27.325
13 27.115 33 27.335
14 27.125 34 27.345
15 27.135 35 27.355
16 27.155 36 27.365
17 27.165 37 27.375
18 27.175 38 27.385
19 27.185 39 27.395
20 27.205 40 27.405
The COBRA21 LTD ST has a vastly superior receiver which includes noise blanker
c i rcuitry and an automatic noise limiter. The receiver also features increased
p rotection against cross modulation and strong adjacent channel signals.
To obtain maximum performance please read carefully the descriptions and
operating instructions in this manual. Fill out below; keep for your records.
Serial No.
Date of Purchase
Dealer Name
Keep this manual for detailed information about your Cobra CB radio.
SAVE YOUR SALES RECEIPT, CARTON AND PACKING FOR POSSIBLE
FUTURE USE.
2
Specifications
21LTDST.MANUAL.REV.QX 9/25/98 10:59 AM Page 5