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Where to locate your CB transceiver.
Your new Midland CB is designed to be installed under the dash or
vertically on a console of your vehicle.
Safety and convenience are the primary considerations in deciding
exactly where to locate your radio.
Caution: Be sure that the unit is located so that it does not interfere with the
driver or impair access to any controls. Connecting cables must be routed
and secured in such a manner as not to interfere with the operation of the
brake, accelerator or other controls. Interference from either the unit or
connecting cables may contribute to the loss of control of the vehicle.
Mechanical mounting
Note: Extreme care should be exercised when drilling into dash to avoid
damage to under-dash electronic ignition, cruise control, instrument and / or
accessory wiring. Your unit must be mounted so as not to interfere with air
bag (SRS) operation.
Step 1: Heeding the caution, use the mounting bracket as a template for
marking the location of screw holes under the dash. Use an awl, nail or
other sharp pointed object to mark the metal.
Step 2: Drill a 1/8” hole for each screw hole in the mounting bracket. Attach
the bracket to the dash with the 3/8” Phillips machine screws provided.
.
Step 3: Locate and secure the radio into the mounting bracket allowing
working space for later power connections.
Power wiring (negative ground only).
Step 1: If you have not determined whether your vehicle has a negative or
positive ground, do so now. Then disconnect the negative lead from the
battery to prevent short circuits that can occur during wiring.
Step 3: With negative ground, connect the red wire (the one with in-line fuse
holder) to either the ( a ) fuse block radio circuit (filtered), ( b ) cigarette
lighter (unfiltered for noise), or ( c ) directly to the positive post on your
battery.
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(Usually, the fuse block is the most convenient connecting point. It is also
possible to connect to the Accessory terminal on the fuse block, so that your
CB automatically goes off when the ignition goes off, preventing accidental
battery drainage.)
The orange wire supplies power for the memory retention feature. For the
memory retention circuit to operate the orange wire must be connected to
power that is not switched off by the ignition switch. The connection point
can be directly to the battery or an unswitched fuse on the fuse block.
(Usually , the fuse block is the most convenient connecting point. It is also
possible to connect the red wire to the Accessory terminal on the fuse block
or ignition switch wo that your CB automatically goes off when the ignition
goes off, preventing a battery drain.)
Note: In many new vehicles the only circuit that has noise filtering is the
radio circuit.
Then tightly connect the black wire directly to the vehicle’s metal
frame. A good direct metal - to - metal ground is essential for optimum
performance. Installations using the cigarette lighter socket for power
require an extra ground wire from the radio chassis to the vehicle if the radio
is not fastened to a grounded part of the vehicle.
Step 3: Plug - in the power cord to the receptacle provided on the back of the
transceiver.
Mounting the main unit.
Step 1: Position the main unit between the bracket arms in line with the
retention knobs. Set the angle for optimum operating comfort and
accessibility.
Step 2: Tighten the retention knobs.
Installation of microphone hanger.
Mounting holes are provided on the microphone hanger bracket. The
bracket can be attached to the vehicle dash, or other convenient location.
Antenna: How to select, position install
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and tune the right one for you.
Basically, you have two types of mobile CB antennas - full-length
whip and loaded whip - and a variety of types of mounts (depending on
where you locate your antenna) to choose from.
Midland markets a broad line of high-performance antennas. The dealer who
sold you your Midland CB can advise which type is best for you.
Where you locate your antenna does make a difference.
Some general rules for antenna location that can aid CB performance:
1. Put your antenna mount as high on the vehicle as possible.
2. The higher the proportion of antenna length that is above the roof, the
better.
3. If possible, mount the antenna in the center of whatever surface you
choose.
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4. Keep antenna cables away from noise sources, such as the ignition
system, gauges, electric fuel pumps, etc.
5. Make sure you have a solid metal - to - metal ground.
6. Exercise care to prevent cable damage.
Essentially, you have five location choices: the roof, gutter, rear deck, front
cowl or rear bumper. Where you decide to locate your antenna will
determine the type of antenna you install. Again consult your Midland CB
dealer for advice and guidance, and measure your needs against the
attributes of the various Midland antenna models he carries.
Antenna installation.
Follow the manufacturer’s installation instructions carefully.
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Warning: Never operate your CB radio without attaching an antenna or with
a broken antenna cable. This can result in damage to transmitter circuitry.
Tuning your antenna.
Some antennas are factory tuned. However, performance can usually be
improved by slightly lengthening or shortening its length, using a Standing
Wave Radio (SWR) meter. For the exact procedures to be used refer to the
antenna manufacturer’s installation manual.
You can buy an SWR meter separately or have your antenna checked by
your Midland CB Dealer’s service department or a two-way comm shop.
77-255ESP
FUNCTION AND LOCATION OF CONTROLS
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FRONT PANEL CONTROLS
1. ROTARY CHANNEL SELECTOR: This easy to operate control allows
changing of weather or CB channel, either up or down. This control will
not operate when the channel “LOCK” function has been activated.
2. MICROPHONE CONNECTOR: Plug in the supplied microphone to this
connector. The collar ring has a screw on locking ring. Push the ring onto
the units collar and screw on until it is tight.
3. ON/OFF VOLUME: In the off position your transceiver’s power is off. Turn
this control clockwise to switch on the unit and adjust the volume.
4. SQUELCH CONTROL: Adjust this control until background noise just
disappears. If the control is adjusted too far clockwise it may cause
muting of weaker signals.
5. RF GAIN CONTROL: This control adjusts the receiver sensitivity. Adjust
the control for best reception of distant or local stations. Begin with
control fully clockwise. To reduce reception of unwanted distant stations,
turn control counter-clockwise until only desired stations are heard.
6. MIC GAIN CONTROL: Rotating this control fully clockwise will result in
the greatest microphone output. /rotating the control counter-clockwise
reduces the microphone output, improving the sound in high noise
environments. This control can also be used to control optional power
microphone output.
7. CHANNEL DISPLAY: LCD (liquid crystal display) read-out of selected CB
or weather channel.
8,11,13. M1, M2, M3 INDICATOR: These LCD boxes are illuminated when a
memory button has been used to select the CB channel.
9. TX INDICATOR: LCD indicator for showing the unit is transmitting.
10. SCAN INDICATOR: This indicates channel scanning is operating.
12. WX INDICATOR: When this indicator is illuminated it indicates your unit
is in the weather receive mode. Weather channels are displayed.
14. S/RF DISPLAY: LCD read-out of received signal strength and relative
transmitter power output.
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15. CB/WX: This button causes your unit to change modes between NOAA
weather bureau receiver and CB operation.
16. M1, M2, M3 BUTTONS: These buttons select CB channels
previously
set by the operator for quick recall. To store channels to memory:
a. Select the desired channel using the rotary channel selector knob.
b. Press and hold the memory button to be set for two seconds. Two
beeps will sound when the channel is memorized.
c. To recall a channel for use, press the desired memory button. The
memorized channel will be selected and displayed.
17. SCAN BUTTON: This button when pressed and when the squelch is
closed causes the channels to be scanned until a signal opens the
squelch. Pressing the button again cancels scanning.
18. TALK BACK SWITCH: This switch allows the user to hear the
transmitted audio as it is transmitted when it is set to “ON”. This
provides the operator with a means to monitor the effects of
microphone gain adjustment and the sound of special audio effects
units.
19. ESP SWITCH: Pressing this button controls the ESP2™ audio system.
Channel noises are reduced and voices enhanced when ESP2™ is
active.
20. BRIGHT/DIM SWITCH: Pressing this button causes the backlighting of
the display to switch between dimmed and full brightness.
BACK PANEL
ANTENNA CONNECTOR: Connect a standard 50-ohm CB antenna to this
connector.
S-METER JACK: A DC voltmeter may be connected to this jack for
precision monitoring of received signal strength.
EXT SPEAKER JACK: When a speaker is connected to this jack the
internal speaker is by-passed. All received signals will be heard through
the external speaker when it is connected. The speaker connected to the
“EXT” jack should be rated at 8 ohms and 5 watts or more.
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HOW TO OPERATE YOUR TRANSCEIVER FOR CB USE
You should become familiar with the controls and complete the preceding
installation instructions before attempting operation of your CB.
1. Adjust the squelch control fully counter-clockwise
2. Rotate the on/off volume control clockwise to turn the unit on. Adjust the
volume for a normal listening level.
3. Select the desired channel by the rotary channel selector. Rotate the
squelch control until the background noise is just quieted. You are now in the
receive mode.
NOTE: If the channel will not change, check that the “
4. To transmit press the PTT bar on the side of the microphone. Hold the
microphone 2 to 3 inches from your lips and speak in a normal voice.
5. To receive simply release the PTT bar.
TO OPERATE YOUR TRANSCEIVER FOR WEATHER RECEIVE
1. Follow steps 1 and 2 above.
2. Press the “WX” button.
3. Using the rotary channel selector select the active channel in your area.
How ESP2™ works to make your CB sound better.
The ESP2™ noise reduction system constantly monitors the signal strength
and the type of noise present. When the signal strength is too low for good
reception, the receiver sound is automatically adjusted to dramatically reduce
the noise that comes through the speaker. While the noise is decreased the
actual sounds you need to hear are increased.
Skip interference can cause whistles and howling sounds. Electrical
interference from power lines, ignition systems or other sources can produce
low humming and buzzing noise. These high and low sounds are not
needed for communications. ESP2™ can determine the difference between
undesired noises and sounds you want to hear and filter the noises out.
These results ESP2™ can accomplish without decreasing receiver range (it
usually increases range). Most importantly, ESP2™ works by itself and does
not need to be listening to other ESP2™ equipped CB’s to be 100%
effective.
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TECHNICAL SPECIFICATIONS
GENERAL
Frequency range ..........................................................................26.965-27.405 MHz
Channels ..............................................................................................................40
Modulation type ...................................................................................................AM
Antenna impedance .......................................................................................50 Ohm
Loudspeaker ...................................................................................................8 Ohm
Microphone ..................................................................................................Electret
Power Supply ....................................................................13.8 VDC negative ground
RECEIVER ( CB, 26.965-27.405 MHz )
Sensitivity at 10db S/N......................................................................................0.6 uV
Selectivity .............................................................................................6 db @ 5 Khz
Squelch range ......................................................................................0.5 uV-500 uV
Audio output power ..................................................3.0 W @ 8 Ohm ( 10% distortion)
Distortion at 1000 mV ............................................................................................3%
Audio frequency response ........................................................................400-2400 Hz
Intermediate frequency .......................................................I ° 10.695 MHz II ° 455 Khz
Spurious response ................................................................ .............more than 45 db
TRANSMITTER
RF Output Power ................................................................................................4.0 W
Frequency Tolerance .........................................................................................0.005%
Harmonic Suppression ..........................................................................More than 60 db
Modulation ...........................................................................................AM 90% ( ± 5%)
SPECIFICATION - WEATHER RECEIVER
CHANNELS
00
01
02
03
04
163.275
162.550
162.400
162.475
162.425
05
06
07
08
09
162.450
162.500
162.525
161.650
161.775
Sensitivity _________________________________1.0 uV for 20 db
Audio Power _______________________________3.0 W
Audio Load ________________________________8 ohms
Intermediate Frequency ______________________455 Khz
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LIMITED WARRANTY.
Midland Consumer Radio will repair or replace, at its option without charge, any Midland Mobile,
Base Station, or full power Hand-Held Citizens Band transceiver which fails due to a defect in
material or workmanship within one year following the initial consumer purchase.
This warranty does not include any carrying cases, earphones, or telescoping antennas which
may be a part of or included with the warranted product, or the cost of labor for removal or re-
installation of the product in a vehicle or other mounting.
Performance of any obligation under this warranty may be obtained by returning the warranted
product, freight prepaid, along with proof of purchase date, to Midland Consumer Radio,
Warranty Service Department 1670 North Topping, Kansas City, Missouri 64120, or to any “
Midland Authorized Warranty Service Station,” or to the place of purchase ( if a participating
dealer).
Warranty information and the location of the nearest “Midland Authorized Warranty Service
Station,” may be obtained by writing Midland Consumer Radio, Warranty Service Department.
This warranty gives you specific legal rights, and you may also have other rights which vary
from state to state.
Note: The above warranty applies only to merchandise purchased in the United States of
America or any of the territories or possessions or from U.S. military exchange. For warranty
coverage on merchandise purchased elsewhere, consult the supplemental warranty information
included with this product or ask your dealer.
SERVICE
If it ever becomes necessary to return your unit for service:
Pack the unit in its original box and packing, Improper packing may result in damage during
shipment. Include $7.50 for return postage and handling. (Note: Some states do not require you
to pay for postage and handling).
Include a full description of any problems. Include your telephone number.
You do not need to return accessory items (brackets, screws, power cord, antenna, etc.) unless
they may be directly related to the problem.
Include a photocopy of the bill of sale or other proof of purchase showing the date of sale. This
information must be included before warranty service can be considered.
A flat rate of $45.00 will apply to repairs not covered by warranty. Send only cashiers check,
money order or Master Card or Visa card number.
MIDLAND
CONSUMER RADIO
1670 N. Topping
Kansas City, Mo. 64120
Printed in China
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FCC Compliance Information
Midland Citizens Band Transceiver
Model 77-255ESP
This device complies with part 15 of the FCC Rules. Operation is subject to the
following two conditions:
(1) This device may not cause harmful interference
(2) This device must accept any interference received including interference that
may cause undesired operation.
For compliance information contact:
Midland Consumer Radio
1670 N. Topping
Kansas City, MO 64120
Tel: (816) 241-8500
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