Cobra_19dx Ii Cb Tranciever_manual

							Nothing
comes close to a Cobra™
PRINTED IN THAILAND ©2002 COBRA ELECTRONICS CORPORATION 480-045-P
6500 WEST CORTLAND STREET
CHICAGO, IL 60707 USA
40 CHANNEL
HOW TO  USE YOUR
CITIZENS BAND
2-WAY MOBILE RADIO 
Model 19 DX 
II 
						

							Serial No.Date of PurchaseDealer Name
Keep this manual for detailed information 
about your Cobra CB Radio System.
SAVE YOUR SALES RECEIPT, THE 
CARTON AND “PACKING” FOR 
POSSIBLE FUTURE USE.If You Think You Need Service, 
please contact your local dealer.
The Cobra
®line of quality products includes:
CB radios
microTALK
®radios
Radar/Laser Detectors
GPS
Safety Alert®
Traffic Warning Systems
Accessories
HighGear
™ Accessories
CITIZENS BAND
2-WAY MOBILE RADIOHOW TO  USE YOUR
40 CHANNEL
Introduction
Frequency Range ........................................................................................2
Specifications ..................................................................................................3
Installation
Location ......................................................................................................4
Mounting and Connections ..................................................................4-5
CB Antenna ................................................................................................6
Ignition Noise Interference ......................................................................7
Operation
Controls and Indicators ....................................................................8-9-10
Operating Procedure to Receive ............................................................11
Operating Procedure to Transmit ..........................................................11
Maintenance and Adjustment ....................................................................12
Appendix
Ten Code ....................................................................................................13
AFew Rules That Should Be Obeyed ..................................................14
How Your CB Can Serve You ................................................................14
Use Channel 9 for Emergency Messages Only....................................15
Model 19 DX 
II 
						

							Frequency Range
Your COBRA CB radio provides high-level, trouble-free performance
over the following frequency assignments:
Channel  Channel Frequency Channel Channel Frequency
in MHz in MHz
126.965 21 27.215
226.975 22 27.225
326.985 23 27.255
427.005 24 27.235
527.015 25 27.245627.025 26 27.265
727.035 27 27.275
827.055 28 27.285
927.065 29 27.295
10 27.075 30 27.3051127.085 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 27.35516 27.155 36 27.365
17 27.165 37 27.375
18 27.175 38 27.385
19 27.185 39 27.39520 27.205 40 27.405
These frequencies are generated and accurately controlled by a phase
lock hoop (PLL) circuit, comprised of the latest state-of-the-art
integrated circuit technology, ensuring high reliability and excellent
frequency stability on the above channels.
To obtain maximum performance please read carefully the 
descriptions and operating instructions in this manual.
2
Introduction
3 GENERAL
Channels 40.
Frequency Range 26.965 to 27.405 MHz.
Frequency Control Phase-Locked Loop (PLL) synthesizer.
Frequency Tolerance 0.005%.
Operating Temp. Range -22
°F to +122
°F (-30
°C to +50
°C).
Microphone Plug-in type; Electret condenser.
Input Voltage 13.8V DC nom. (negative ground).
Current Drain Transmit: AM full mod., 1.5A (maximum).
Receive: (Squelched, 0.115A, full audio
output 1.0A (nominal).
Size 6-5/8”D x 4-9/16”W x 1-13/16”H
(165mm x 116 mm x 44 mm.)
Weight 3 lbs., 4 oz. (1.0 kg.).
Antenna Connector UHF, SO-239.
Semiconductors 22 transistors, 17 diodes, 3 integrated
circuits, 7 LEDs.
Meter Indicates relative power output and
received signal strength.
TRANSMITTERPower Output 4 watts.
Modulation High- and low-level Class B amplitude.
Frequency 300 to 3000 Hz.
Output Impedance 50 ohms, unbalanced.
Output Protection Output transistors protected against
mismatch up to 20:1.RECEIVERSensitivity Less than 1µV for 10dB(S + N)/N.
Selectivity 6 dB @ 7 KHz, 55dB @ 15 KHz.
Image Rejection 60 dB typical.
Adjacent CH. Rejection 50 dB, typical.
IF Frequencies Double conversion,  1st: 10.695 MHz.
2nd: 455 KHz.
Automatic Gain Control Less than 10dB change in audio output for 
(AGC) inputs from 10 to 50,000µV.
Squelch Adjustable; threshold less than 1µV.
Audio Output Power 3 watts.
Frequency Response 300-3000 Hz.
Distortion Less than 10% @ 3 watts @ 1000 Hz.
Built-in Speaker 8 ohms, round.
External Speaker 8 ohms; disables internal speaker when 
(Not Supplied)
connected.
PASYSTEMPower Output 4 watts into external speaker.
External Speaker for PA 8 ohms; a separate jack is provided.
(Not Supplied)
(Specifications subject to change without notice.)
Specifications 
						

							Location
Plan the location of the transceiver and microphone bracket before
starting the installation. 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 usually mounted to the
underneath of the dash panel, with the microphone bracket beside it.
Mounting Connection
The transceiver is held in the universal mounting bracket by two
thumb screws, permitting adjustment at the most convenient angle.
Auniversal mounting bracket is supplied along with self tapping
screws and star washers. The mounting must be mechanically strong
and also provide a good electrical connection to the chassis of the
vehicle. To mount the transceiver:
1.
Determine the most convenient location in your vehicle. Hold the
COBRA radio with mounting bracket in the exact location desired.
If nothing will interfere with mounting it in the desired position,
remove the mounting bracket and use it as a template to mark the
location for the mounting screws.
2.
Drill necessary holes and secure mounting bracket in location.
4
Installation
5
3.
Connect the antenna cable plug to the standard receptacle on the
unit. Most CB antennas are terminated with a type PL-259 plug
which mates with the receptacle marked “ANT.”
4.
Connect the red lead of DC power cord to +13.8VDC. In 
automobile installations, +13.8VDC is usually obtained from the
accessory contact in the fuse box. This prevents the set being left
on accidentally and also permits operating the unit without the
vehicle’s engine running.
Before installing the CB radio, visually check the vehicle
battery connections to determine which battery terminal,
positive or negative (positive is the larger of the two) is
grounded to the engine block (or chassis).
5.
Connect the black lead to the negative side of the automobile.
This is usually the chassis of the car. Any convenient location with
good electrical contact (remove paint) may be used.
6.
Mount the microphone bracket on right side of the transceiver, or
near it using two screws supplied. When mounting in an
automobile, place the bracket under the dash so the microphone is
readily accessible.
Installation (Cont.) 
						

							CB Antenna
Since the maximum allowable power output of the transmitter is
limited by the FCC, the antenna is one important factor affecting
transmission distance. Only a properly matched antenna system will
allow maximum power transfer from the 50-ohm transmission line to
the radiating element. In mobile installations (cars, trucks, boats, etc.),
an antenna system that is non-directional should be used.
Avertically polarized, quarter-wavelength whip antenna provides the
most reliable operation and greatest range. The shorter, loaded-type
whip antennas are more attractive, compact and adequate for
applications where the maximum possible distance is not required.
Also, the loaded whips do not present the problems of height imposed
by a full quarter-wavelength whip.
Mobile whip antennas utilize the metal body of the vehicle as a
ground plane. When mounted at a corner of the vehicle they are
slightly directional, in the direction of the body of the vehicle. For all
practical purposes, however, the radiation pattern is nondirectional.
The slight directional characteristic will be observed only at extreme
distances. A standard antenna connector (type SO-239) is provided on
the transceiver for easy connection to a standard PL 259 cable
termination. Cobra loaded-type antenna models ATW-500, AT-55,
ATW-1000 and ATW-400 are highly recommended for most
installations. Consult your Cobra dealer for further details.
When installed in a boat, the transceiver will not operate at
maximum efficiency without a ground plate, unless the vessel has a
steel hull. Before installing the transceiver in a boat, consult your
dealer for information regarding an adequate grounding system and
prevention of electrolysis between fittings in the hull and water.
3-Way Combinations Antennas are available which allow operation
of all three bands (AM-FM & CB), using a single antenna. However,
use of this type of antenna usually results in less than normal
transmit and receive range when compared to a standard-type
“Single Band” antenna designed for CB only.
6
Installation (Cont.)
Ignition Noise Interference
Use of a mobile receiver at low signal levels is normally limited by the
presence of electrical noise. The primary source of noise in automobile
installations is from the alternator and ignition system in the vehicle.
Under most operating conditions, when signal level is adequate, the
background noise does not present a serious problem. Also, when 
extremely low level signals are being received, the transceiver may be
operated with vehicle engine turned off. The unit requires very little
current an therefore will not significantly discharge the vehicle battery.
Even though the COBRA radio has an automatic noise limiter, in 
some installations, ignition interference and other forms of automobile 
generated noise may be high enough to make good communications
difficult. The electrical noise may come from several sources. Many
possibilities exist and variations between vehicles require different
solutions to reduce the noise. Consult your COBRA dealer or a 2-way
radio technician for help in locating and correcting the source of 
severe noise.
Base Station Operation (Operation from 120VAC, House Current)
To operate your transceiver from your home or office, using the
regular house current as the power source, you will require a 12VDC
power pack that has been specially designed for the purpose. It is
available as optional equipment from your COBRA dealer. It consists
of a 120-volt, 60 Hz AC to 12-volt DC power converter with a 3A
rating. Simply connect the red (+) and black (-) leads of the transceiver
to the corresponding terminals of the power packs.
DO NOT ATTEMPT TO OPERATE THIS TRANSCEIVER BY 
CONNECTING DIRECTLY TO 120 VAC. SERIOUS DAMAGE
WILL RESULT.
Temporary Mobile Operations
To operate your COBRA transceiver from a car on a temporary basis,
you may want to purchase an optional cigar lighter adapter from your
COBRA dealer. This adapter and a magnetic mount antenna allow you
to quickly "install" your transceiver for  temporary use.
7Installation(Cont.) 
						

							Controls and Indicators
Refer to controls, indicators and connectors as illustrated below:
3
89
A. Front Panel1.
Off/On/Volume. Turn clockwise to turn power on and set the
desired listening volume.
2.
Squelch. 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. Adjust until the receiver
noise disappears. This will require the incoming signal to be
slightly stronger than the average receiver 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.
Microphone Connector. This front mounted, screw-on connector
allows for convenient removal of the microphone plug when
storage is required. The microphone MUST be connected to the
unit at all times when in use, for proper operation. The screw-on
connection enhances the life of the microphone cord as well.
4.
Channel 9/Normal Switch. Used for instant selection of
emergency channel 9 (CH 9 position). In NOR position, all 40 CB
channels are selected by the UP/DOWN CHANNEL BUTTONS.
8
2
1
4
5
67
Operation 
9
5.
CB/PA Switch. Selects mode of operation. In the CB position, the PA
function is disabled and the unit will transmit and receive on the
selected channel. The PA function should not be used unless a PA
speaker is connected.
6.
S-RF/Power Meter. Shows relative transmitter RF output power
and input signal strength when receiving. The five LED (Light
Emitting Diode) segments glow to indicate receive or transmit
activity. 
7.
TX Indicator LED. This indicator will light red when in the
transmit mode.
8.
LED Channel Display. The selected operating channel will be
displayed here.
9.
Channel Selector Switch. When turned, this knob is used to
select any one of the forty citizens band channels desired.
For a “RAPID” change of channels, depress and hold the desired
button (up and down). This allows all 40 channels to be covered
in about 6 seconds.
Other Operation Features•Automatic Noise Limiter. This is a non-switchable feature that
is always on to reduce background noise.
Operation (Cont.) 
						

							B. Rear Panel1.
ANTENNA CONNECTOR:This SO-239 connector permits
connection of the transmission line cable male connector to the
transceiver.
2.
PUBLIC ADDRESS:An external 8-ohm 4.0 watt PA speaker may be
connected to the PA Speaker Jack when this unit is used as a public
address system. The speaker should be directed away from the 
microphone to prevent acoustic feed-back. Physical separation or
isolation of the microphone and speaker must be employed when
operating the PA at high output levels.
3.
EXTERNAL SPEAKER:The External Speaker Jack is used for
remote receiver monitoring. The external speaker should have 
8-ohm impedance and be rated to handle at least 4.0 watts. When
the external speaker is plugged in, the internal speaker is
automatically disconnected.
4.
POWER:These wires supply power to the CB radio. See page 5 for
installation.
10
1
2
3
4
Operation (Cont.) 
Operating Procedure to Receive
1.
Be sure that the power, antenna and microphone are properly 
connected before proceeding further. The CB/PA switch should be
in the CB mode. The Channel 9/NOR Switch should be in the
NOR mode.
2.
Turn the radio ON by rotating the VOLUME CONTROL
clockwise.
3.
Rotate SQUELCH CONTROL counterclockwise until incoming
signal is heard.
4.
Turn the CHANNEL SELECTOR KNOB to select the desired 
operating channel.
5.
Set the VOLUME CONTROL to a comfortable listening level.
Listen to the background noise from the speaker. Turn the SQUELCH
CONTROL slowly clockwise until the noise JUST disappears (no
signal should be present). Leave the control at this setting. The
squelch is now properly adjusted. The receiver will remain quiet until
a signal is actually received. Do not advance the control too far, or
some of the weaker signals will not be heard.
Operating Procedure to Transmit
1.
Select the desired channel.
2.
Press-to-Talk Switch.The receiver and transmitter are controlled
by the press-to-talk switch on the microphone. Press the switch
and the transmitter is activated; release switch to receive. When
transmitting, (on a clear channel), hold the microphone two inches
from the mouth and speak in a clearly normal voice.
Be sure the antenna is properly connected to the radio before
transmitting. Prolonged transmitting without an antenna, or a
poorly matched antenna, could cause damage to the transmitter.
Operating Procedure for Public Address
1.
Connect a PA speaker to the PA jack provided on the rear panel.
2.
Set the CB/PA switch to the PA position.
3.
Depress the push-to-talk switch on the microphone and speak in a
normal voice.
4.
Adjust the volume of the PA speaker using the Volume control on
the front panel.
11
Operation (Cont.) 
						

							Your COBRA CB transceiver is specifically designed for the
environment encountered in mobile installations. The use of all solid
state circuitry and its light weight result in high reliability. Should a
failure occur, however, review the following, then if necessary replace
parts only with identical parts. Do not substitute. Refer to the
schematic diagram and parts list.1.
Check connections to the source of power and make sure it is the
13.8 VDC required to operate your radio.
2.
Check the fuse in the DC power cord. The main power lead (red
wire) has a 2 Amp 3 AG type fuse installed. Use only the above
specified type and size fuse for maximum protection. Failure to do
so, will void the warranty.
3.
Make certain the microphone is properly plugged in.
4.
Make certain the antenna is properly connected and tuned for 
minimum SWR. NOTE: COBRA antennas include full instructions
for tuning your antenna. If you’re still in doubt about the
procedure, contact the COBRA dealer from whom you purchased
your radio and antenna, for advice. If you hired an installer to
install your radio and antenna, contact him.
If you are unable to correct the problem, please contact your local
dealer.
Adjustment Warning
When making adjustments other than transmitter adjustments, be sure
to re-read applicable portions of this instruction manual to make
certain you are following correct procedure and that the radio was
properly installed, etc.
12
Maintenance and Adjustment
Citizens Band radio operators have largely adopted the “10-code”
for standard questions and answers. Its use permits faster 
communications and better understanding in noisy areas. The
following table lists some of the more common codes and their
meanings:
10-CODE
Code Meaning Code Meaning
10-1 Receiving poorly 10-35 Confidential information
10-2 Receiving well 10-36 Correct time is
10-3 Stop transmitting 10-37 Wrecker needed at
10-4 OK, message received 10-38 Ambulance needed at
10-5 Relay message 10-39 Your message delivered
10-6 Busy, stand by 10-41 Please turn to channel
10-7 Out of service, leaving air 10-42 Traffic accident at
10-8 In service, subject to call 10-43 Traffic Tie up at
10-9 Repeat message 10-44 I have a message for you
10-10 Transmission completed, 10-45 All units within range
standing by please report
10-11 Talking too rapidly 10-50 Break channel
10-12 Visitors present 10-60What is next message 
number?
10-13 Advise Weather/Band 10-62 Unable to copy, use phone
conditions 10-63 Net directed to
10-16 Make pick up at 10-64 Net Clear
10-17 Urgent business 10-65 Awaiting your next
10-18 Anything for us? message/assignment
10-19 Nothing for you, return 10-67 All units comply
to base 10-70 Fire at
10-20 My location is 10-71 Proceed with transmission 
10-21 Call by telephone in sequence
10-22 Report in person to 10-77 Negative contact
10-23 Stand by 10-81 Reserve hotel room for
10-24 Completed last assignment 10-82 Reserve room for
10-25 Can you contact 10-84 My telephone number is
10-26 Disregard last information 10-85 My address is
10-27 I am moving to channel 10-91 Talk closer to mike
10-28 Identify your station 10-93 Check my frequency on
10-29 Time is up for contact this channel
10-30Does not conform to FCC rules10-94 Please give me a long count
10-32 I will give you a radio check 10-99 Mission completed, all
10-33 EMERGENCY TRAFFIC units secure
10-34 Trouble at this station 10-200 Police needed at
13
Appendix 
						

							14 AFew Rules That Should Be Obeyed
1.
You are not allowed to carry on a conversation with another station for
more than five minutes at a time without taking a one-minute break, to
give others a chance to use the channel.
2.
You are not allowed to blast others off the air by overpowering
them with illegally amplified transmitter power, or illegally high
antennas.
3.
You can't use CB to promote illegal activities.
4.
You are not allowed to use profanity.
5.
You may not play music in your CB.
6.
You may not use your CB to sell merchandise or professional
service.
How Your CB Can Serve You
•Warn of traffic tie-ups ahead.
•Provide weather and road information.
•Provide help fast in event of emergency or breakdown.
•Suggest good spots to eat and sleep.
•Make long trips more interesting, and help keep you awake.
•Provide direct contact with your office or home.
•Make friends for you as you travel.
•Provide "local information" to find your destination.
•Help law enforcement officers by reporting drunk and reckless drivers.
Appendix (Cont.)
15 Yes”Atornado sighted six miles (10 km) north of town.”
No ”This is observation post number 10. No tornado 
sighted.”
Yes”I am out of gas on Interstate 95 at mile marker 121.”
No ”I am out of gas in my driveway.”
Yes“There is a four-car collision at Exit 10 on the Beltway, 
send police and ambulance.“
No “Traffic is moving smoothly on the Beltway.“
Yes”Base to Unit 1, the Weather Bureau has just issued a
thunderstorm warning. Bring the sailboat into port.”
No “Attention all motorists. The Weather Bureau advises
that the snow tomorrow will accumulate 4 to 6 inches
(10 to 15 cm).”
Yes“There is a fire in the building on the corner of 6th and
Main Streets.“
No ”This is Halloween patrol unit number 3. Everything is
quiet here.” Use Channel 9 For Emergency Message Only
FCC give the following examples of permitted and prohibited types of
communications for use on Channel 9. These are guidelines and are
not intended to be all-inclusive:
Permitted: Example Message:
Appendix (Cont.) 
						

							Nada
se compara a Cobra™
IMPRESO EN TAILANDIA ©2002 COBRA ELECTRONICS CORPORATION 480-045-P
6500 WEST CORTLAND STREET
CHICAGO, IL 60707 USA
40 CANALES
INSTRUCCIONES DE USO DEL
RADIO BIDIRECCIONAL
MÓVIL DE BANDA
CIUDADANA
Modelo 19 DX 
II