Location
Mounting the Connection
Ignition Noise Interference
Antenna
.
Tuning the Antenna for Optimum SWR
Ext . Speaker -7
Operation
Control Functiom
Front Panel
RearPanel
Press-To-~alk Microphone 11
Operatiq Procedure to Receive 11
O~erating Procedure to Transmit 11
Receiving
RogerBeep
Alternate Microphones and Installation
A
Frequency Range
...........................................
................................
...............................
...........................................
.......................
........................................
.....................................
.........................................
.........................................
...............................
............................
..........................
SSB
signais
..................................
........................................
......................
Few Rules That Should
~e
Obeyed
.......................
.........................................
4
4
5
5
6
8
8
10
11
13
14
17
18
Page 3
Page 4
Frequency Response
Output Impedance
Output Indicators
RECEiVER
Sensitivity
Selectivity
Image Rejection
IF
Frequency
Adjacent-Channel Rejection
RF
Gain Control
Automatic Gain Control
(AGCI
Squelch
ANL
Noise Blanker
Clarifier Range
Audio Output Power
Frequency Response
Built-in Speaker
Extemal Speàker
(Not Supplied)
450
to
2500
AM and FM:
50
ohms, unbalanced.
Hz.
Meter shows relative RF output power and
SWR. Transmit LED
glows red when trans-
mitter is in operation.
0.25
pV
for
10
SSB:
dB (s+N)/N at greater
than %-watt of audio output.
1.0
pV
for
10
AM:
dB (S+N)/N at greater
than %-watt of audio output.
1 .O
pV
for
20
FM:
dB (S+N)/N at greater
than Kwatt of audio output.
AM/FM: 6 dB
6
SSB:
than
More
AMIFM:
SSB:
10.695
60
dB AM/FM
45
dB adjustable for .optimum signal recep-
@3
KHz,
dB ($2.1 KHz,
65
dB.
10.695
MHz 1st
MHz.
&
70
dB SSB.
50
dB @ KHz.
60
dB
IF,
@3.3
455
KHz.
KHz 2nd
tion.
Less than
inputs from
Adjustable; threshold less
10
dB change in audio output for
10
to
100,000
microvolts.
than
0.5
pV,
Switchable.
RF type, effective on
Coarse
4
8
(TX/RX)
Fine
(TX/RX)
watts into 8 ohms.
300
to
2800
Hz.
8
ohms, round.
ohms; disables interna1 speaker when con-
AM/FM and SSB.
25
KHz.
21
KHz. (or RX
only)
nected.
IF
Page 5
Installation
LOCATION
Plan the location of the transceiver and microphone bracket before starting
the installation. Select a location that is convenient for operation and
interfere with the driver or passengers in the vehicle. In automobiles, the transceiver is usually
beside it.
rnounted.below the dash panel, with the microphone bracket
MOUNTINC THE CONNECTION
Your transceiver
mounting the bracket and radio to your car,
Also provide a good electrical connection to the chassis of the vehicle. Proceed
as
foiiows to mount the transceiver:
1.
After you have determined the most convenient location in your vehicle, hold
the transceiver with mounting bracket
nothing will interfere with rnounting it
mounting bolts.
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 PL-259 plug and mate with the
receptacle.
3. Connect the red DC power input wire (with the fuse) to
extends from the rear panel. In automobile installation, +13.8V
wire
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 receiver in the car.
4.
Connect the black lead to -13.8V
Any convenient location with good
used.
S.
Mount the microphone bracket on the right side of the transceiver or near the
transceiver, using two screws supplied. When mounting in
place the bracket
is
supplied with a universal mounting bracket. When
make sure it is mechanicaliy strong.
in
the exact location desired.
in
the desired position, rernovG the
Before drilling the holes, make sure nothing will interfere
+13.8V DC. This
DC.
This is usually the chassis of the car.
electrical contact (remove paint) may be
under the dash so the microphone is readily accessible.
does not
an
automobile,
DC
If
is
Page 6
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 generator and ignition system in the vehicle.
operating
not present a serious problem. Also, when extremely low level signals are being
received, the transceiver
unit requires very
vehicle battery.
Even though the transceiver
ignition interference may be
impossible. The electrical noise may
ties exist and variations between vehicles require different solutions to reduce
the noise.
coriditions, when signal level is adequate, the background noise does
mây be operated with vehicle engine turned off. The
little current and therefore will not significaritly discharge the
has
ANL
and
NB
controls, in some installations
high enough to make good communications
come from several sources. Many possibili-
Under most
ANTENNA
A
vertically polarized, quarter-wavelength whip antenna provides the most
reliab!e operation and greatest range. Shorter, loaded-type whip antennas art:
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
Mobile whip antennas utilize the
When mounted at
direction of the body of the vehicle. For
radiation pattern is nondirectional. The
observed only at extreme distances.
239)
is provided on the transceiver for easy connection to a standard
cable termination.
If the transceiver is not mounted on a
separate ground wire from the unit to a good metal electrical ground in the
vehicle. When installed in a boat, the transceiver
efficiency without a ground plate, unless the
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.
a
corner of the vehicle they are slightly directional, in the
quarter-wavelength whip.
metal body of the vehicle as a ground plane.
al1 practical purpose, however, the
slight directional characteristic will be
A
standard antenna connector (type SO
PL
259
metal surface, it is necessary to run a
wiil not operate at maximum
vesse1 has a steel hull.
Page 7
TUNING THE ANTENNA FOR OPTIMUM SWR
Since there is such a wide variety of base and mobile antennas, this section
will strictly concern itself to the various types of mobile adjustable antennas.
Because the antenna length is directly related to the channel frequency, it
/
must be tuned to resonate optimdy
1
requires a longer antenna than charnel
Due to the
chosen what we think is the optimum method:
A.
Antennas with adjustment screws (set screws).
Start with the antenna extended and tighten the set screw lightly enough so
1.
that the antenna
2.
Set your transceiver to Channel
switch, and tap the antenna
a lower reading each
the antenna you wili notice the SWR reading wiii reach a low print and then
start rising again. This means that you have passed the optimum point for
Channel
procedure
When the lowest point has been reached, switch to Channel
F
or
readings. They sould be almost equal.
B.
Antennas which must be cut to proper length.
1.
FoUow the same procedure as above, but adjust the length by cutting in 1/g"
increments until a good match is obtained.
2.
Be vev carefui not to cut too much at one time, as one it is cut. it can no
longer be lengthed.
3.
The whip iseasily cut by filing a notch al1 the way around and breaking the
piece off with pliers.
various methods of adjusting antennas for proper SWR we have
can be lightly tapped with your finger for easy adjustment.
the the antenna is tapped. By continuing to shorten
21.
Extend the antenna a short distance and again foiiow the
above.
band and then to Channel 40 @ A band or F band and compare SWR
d
271
channels of the transceiver. Channel
271
because it is lower in frequency.
2.1
@
C band. Press the PTT (push-to-tak)
(making it shorter). The SWR meter wiii show
1.
@
A band
7-
THE PROPER SETTINC IS ACHIEVED WHEN THE SWR IS 1.5 OR
BELOW, AND
CHANNEL 1 AND F BAND CHANNEL 40.
If you are having difficulties in adjusting your antenna, check the following:
Ali
doors must be closed when adjusting the antenna.
A.
B. Make sure the antenna base is grounded.
C. Check your coaxial
car).
WHEN IT HAS THE SAME READING FOR A BAND
cable routing (it may be pinched when routed into the
NOTE
P
Page 8
D.
Try a different location on your car (keeping in mind the radiation pattern
you wish).
E.
1s the antenna perfectly vertical?
F.
Try a different location in your neighborhood. Stay away from large metai
objects when adjusting (metal telephone or light posts, fences, etc.)
The TRANSCEIVER will
sustain an SWR of 20:l for a maximum of 5 minutes at rated
and
operating conditions.
rNOTE1
Ex
temal
The extemai speaker jack (EXT. SPK.) on the rear panel is used for remote
receiver. monitoring. The extemal speaker should have 8 ohms impedance and be
able to handle at least
internal speaker is disconnected.
Speaker
4
operate into an SWR of 2 to 1 indefinitely
watts. When the externai speaker is plugged in, the
Page 9
Operation
CONTROL FUNCTIONS
There are Fifteen controls and four indicators on the front panel of your
transceiver
1
FRONT
I.
2.
3.
4.
PANEL
OFF/ON/VOLUME
the desired
trol is used to adjust the output level obtained either at the transceiver
speaker or the
SQUELCH
noise in the absence of
it
is
desired that the control
background noise or ambient background noise
terclockwise then slowly clockwise until the receiver noise disappears.
signal to be received must now
noise.
signal
at
a
MIC
transmit and
power is availabie
RF
CAM
RF
aniplifier under strong signal conditions.
listening level.
This control is used. to cut off or eliminate receiver background
Further clockwise rotation
must overcome
maximum clockwise setting.
GAIN
CONTROL
Turn clockwise to apply power to the
Dunng
extemal speaker, if used.
aq
in
order to
(inner
dud
concentnc). Adjusts the microphone gain in the
PA
modes. This controls the gain to the extent that full talk
several inches away from the microphone.
(outer
normal
incoming signal. For maximum receiver sensitivity
be
adjusted oniy to the point where the receiver
be
wiii
be
dud
CB
operatioq the
is
eliminated. Tum
slightly stronger
increase the threashold level which a
heard.
concentnc). Use to reduce the gain of the
Only
strong signals
than
unit
VOLUME
the
average received
wiil
and to set
con-
fully
coun-
Any
be heard
5.
SWR
CAL CONTROL
maximum radiated power and the
antenna be in good condition, properly adjusted and matched to your
transceiver. The built-in
(inner concentric). In order for you to achieve
longest range, it is important that your
SWR
(standing wave ratio) meter lets you easily
Page 10
measure your antenna condition. To operate this function, connect your
antenna to the transceive antenna output
near the middle of the band
frequently. Turn the power on and set the
CAL position.
the SWR CAL control, adjust the
on the
the
meter face. Then, without releasing the microphone button, switch
meter function switch to the SWR position and read the SWR indicated.
The lower the figure, the better with 1 being
reading up to 3 are acceptable, but over 3 indicates that yoù are losing
radiated power and antenna adjustment may be advisable.
Ress and hold the microphone push-to-taik button and using
such as 2 1 or the channel you plan to use most
meter to read the CAL position indicated
connector. Select a channel
meter function switch to the
ideal. Generaiiy speaking,
1
RF POWER (outer concentric). Adjust this control to acquire RF power
AM
level you desired in
6.
BAND SELECTOR. This switch selects A,
7.
MODE (FM/AM/USB/LSB) SWITCH. This switch is used to select
FM, AM,
communication is desired is equipped with SSB, the AM or FM mode is
normally used. The mode selector switch changes the mode of operation of
both transmitter and receiver sirnultaneously. Turn to
signais" for a further explanation of single sideband.
8.
CLARIFIER. ~116~s variation of the receiver operating frequencies above
and below the assigned frequency. Although this control is intended
prirnarily to tune in SSB signals, it rnay be used
as described in the Operating
operates both TX/RX. (or Fine only
9.
CHANNEL SELECTOR. This switch selects any one of the forty Citizens
Band channels desired. The selected channel
directly
METER.
10.
output power and SWR level.
+10KHz FREQUENCY SHIFT SWITCH. When switch is pressed the
11.
frequency is shifted
used by setting this switch to
LSB or USB mode of operation. Unless the station with which
above the Channel Selector knob.
This meter indicates received signai strength, transmitter
or FM transmission.
B,
C,
Procedure paragraphs. Coarse and Fine
in
RX)
appears on the
lOKHz up. On following channels.
+10KHz position
Normal
D.
E, F band of operation.
I'Receiving SSB
to
ptimize AM/FM signals
LED
A channel
readout
RF
can be
3
7
11
15
19
12. ROGER BEEP SWITCH: When this switch is placed in the ROGER BEEP
position, your radio autornatically transmits the audio sign at the end of
your transmission. The
through the sign.
listener can note easily your transmission is over
1
1
Page 11
13. SWR/CAL SWITCH. When in the "CAL" position, the SWR meter can be
calibrated by adjusting the "SWR CAL" control to the "CAL" mark on the
meter face.
When
in
the "SWR" position, the standing wave ratio is measured.
OFF-NB/ANL SWITCH. In the NB/ANL position, the RF noise blanker is
14.
activated and automatic noise limiter in the audio circuits is also activated.
The RF noise blanker is
very effective for repetitive impulse noise such as
ignition interference.
15. COUNTER SWITCH-ON/OFF. Depressing this switch causes the receiver
or transmitter frequency to be
S/RF SWITCH. In the S/RF position, the meter swings proportionally to
16.
displayed on the frequency counter.
the strength of the received signal. When transmitting, the meter indicates
relative RF output power.
17. FREQUENCY
selected
charnel you wish to operate on.
COUNTER.
The frequency counter indicates the of the
18.RECEIVE /TRANSMIT INDICATOR. The receiver/transmit LED indicator
located next to the channel indicator. When in receive, the LED will be
is
green. When in transmit the LED will be red.
19.CHANNEL INDICATOR. Numbered LED indicates the selected channel you
wish to
operate on.
REAR PANEL
20. POWER. Accepts
connected.
21. EXT SP. Accepts 4 to 8 ohm, 5 watt external speaker to be connected.
When external speaker is connected to this jack, the built-in speaker is
automatically disconnected.
ANTENNA. Accepts
22.
connected
.
13.8V
DC power cable with built-in fuse
50
ohm coaxial cable with a type
(4
PL-259
amp.) to be
plug to be
Page 12
PRESSTO-TALK MICROPHONE
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, hold the microphone two
and speak clearly in a normal "voice".
impedance
other microphones,
INSTALLATION."
(500
ohm) dynamic microphone. For installation instructions on
see next section, "ALTERNATE MICROPHONES AND
The radios
inches from the mouth
come complete with low-
OPERATiNG PROCEDURE TO RECEIVE
1.
Be sure that power source, microphone and antenna are connected to the
connectors before going to the next step.
proper
2.
Turn unit on by tuning VOLUME control clockwise
3.
Set the VOLUME for a comfortable listening level.
4.
Set the MODE
5.
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
not
advance the control too far, or some of the weaker signals will not be
heard.
6.
Set the CHANNEL selector switch to the desired channel.
7.
Set the RF gain control fully clockwise for maximum RF gain.
8.
Adjust the CLARIFIER control to clarify the SSB signals or to optimize
AM/FM signals.
switch to the
desire mode.
remain quiet until a signal is actually received. Do
OPERATING PROCEDURE TO TRANSMIT
1.
Select the desired channel of transmission.
2.
Set the MIC GAIN control fully clockwise.
3.
If the channel is clear, depress the push-to-talk switch on the microphone and
speak in a normal voice.
1
1
I
I
RECEIVING
There are four types of signals presently used for communications in the
Citizens Band: FM,
placed in the
only frequency deviation, full carrier signals will be detected. An SSB signal
may
be recognized while in the
Duck" sound and the inability of the AM or FM detector to
ligible output. The USB and LSB modes will detect upper
sideband respectively, and standard
SSB
SIGNALS
AM,
USB, and LSB. When the MODE switch on your unit is
AM
position, only standard double-sideband and in FM position,
AM
or FM mode by its characteristic "Donald
produce an intel-
sideband and lower
AM
signals.
Page 13
SSB reception differs from standard
not require a carrier or opposite sideband to produce an intelligible signal. A
single-sideband transmitted signal consists only of the upper or the lower
band and no carrier is transmitted. The elirnination of the carrier from the
signal helps to eliminate the biggest cause of whistles and tones heard on channels which make even moderately strong AM signals unreadable. Also, SSB takes
only half of an AM
charnel, expanding the
channel space required also helps in the receiver
and interference
An SSB signal may be received only when the listening receiver
in the
same mode. In other words, an upper sideband signal (USB) may be made
intelligible
If a lower
mode, no
may be understood if you
transrnitter's microphone in the USB mode, the transmitter's output frequency
is increased whereas in the
creased. The result in listening to the receiver is that when the MODE switch is
in the proper position (either USB or LSB), a true reproduction of single tone of
modulation will result, and if the tone is increased in frequency
pitched whistle a high-pitched whist!e) you will hear the increase in the output
tone of the receiver. If the incorrect mode is selected, an increase in tone of a
whistle applied to the transmitter will cause a decrease in the resultant tone from
the receiver.
Thus when a voice is used in place of a whistle or tone, in the proper listening
mode the voice will be received correctly whereas in the incorrect mode, the
voice will be translated backwards and cannot be made intelligible by the voice
lock control. When listening to an
in either mode
Once the desired SSB mode has been selected, frequency adjustment may be
necessary in order to make the incoming signal intelligible, the CLARIFIER
control allows the
frequency of the received signal. If the sound of the incoming signal is high or
low pitched, adjust the operation of the CLARIFIER.
the
voices will be high-pitched and if set too low, voices will be low-pitched.
there is only
same sound that was recorded. If the record is played on a turntable that rotated
in
(CLARIFIER) will
An AM signal received
steady tone (carrier) in addition to the intelligence, unless the SSB receiver
tuned to exactly the
'it
is recommended that the
only
amount of tuning will make the signal intelligible. The reason for this
same function as a phonograph speed control. When the speed is set to high,
the wrmg direction (opposite sideband) no amount of speed control
channel, therefore two SSB conversations will fit into each
271
AM
channels to
can be received with
if the receiver is functioning in the USB position.
sideband (LSB) signal is heard when the receiver is in the USB
consider that when modulation is applied to the
LSB
since both upper and lower sideband are received.
operator to Vary frequency above and below the exact-center
one
correct speed that will make a particular record produce the
produce an intelligible sound.
while listening in one of the SSB modes will produce
same freqiiency by the CLARIFlER control. For simplic t
AM
modes be used to listen to
AM
reception in that SSB receiver does
side-
AM
542
SSB channels. The reduction in
because only
100%
of the SSB signal.
mode the transmitter's output frequency is de-
AM
transmission, a correct sideband is heard
Consider it as performing
AM
half
of the noise
is functioning
(such as a low-
signals.
Also,
Page 14
ROGER BEEP
When this switch is placed in the ROGER BEEP position, your radio automatically transmits the audio sign at the end of ywr- transmission. The listener
can note easdy that your transmission is over through the sign. Please note that
this ROGER BEEP transmits 0.15-second at the moment PRESS-TO-TALK
SWITCH KNOB is off.
Fig.
2.
- - -
- -
- -
2
--------------
+
PRESS-TO-TALK ON PRESS-TO-TALK OFF
---L----
1
-
TX
Page 15
1
ALTERNATE MICROPHONES
For best results, the user should select a low-impedance dynamic type micro-
phone or a transistorized microphone. Transistorized type microphones have
low output impedance characteristic. The microphones must be provided with a
four-lead
leads. The
The microphone should
cable. The audio conductor and its shielded lead comprise two of the
fourth lead is for receive control, and third is for transmit control.
provide the functions shown in schematic below.
Pin
Number Mic Cable Lead
1
2
3
4
4
WIRE
AND
INSTALLATION
MIC CABLE
Audio Shield
Audio Lead
Transmit Control
Receive Control
a
Fi.
3.
Your transceiver microphone schematic.
If the microphone to be used is provided with
as follows.
1. Cut leads so that they
the microphone
2.
All leads shoudl be cut to the same length. Strip the ends of each wire 118"
and tin the exposed wire.
Before begining the
mation provided with the microphone
quired in soldering the connections. Keep the exposed wire lengths to a minimum to avoid shorting when the microphone plug
cable.
extend 7/16" beyond the plastic insulating jacket of
actual wiring read carefully, the circuit and wiring infor-
pre-cut leads, they must be revised
you select. Use the minimum head re-
is reassembled.
Page 16
1
KNURLED
1
PIN
RECEPTACLE
A.
MICROPHONE CONNECTOR ASSEMBLY
WASHER
/
B. MICROPHONE CONNECTOR DISASSEMBLED FOR WlRlNG
Fig.
4.
Microphone plug wiring.
1.
Remove the retaining screw.
2.
Unscrew the housing from the pin receptacle body.
3.
Loosen the two cable clamp retainer screws.
4.
Feed the microphone cable through the housing, knurled ring and washer as
shown Fig.
5.
The wires must now be soldered to the pins as indicated in the above wiring
tables. If a vise or clamping tool is available it should be used to hold the pin
receptacle body
perform the soldenng. If a vise or clamping tool is not available, the pin receptacle body can be held in a stationary position by inserting it into the
microphone jack of the front panel. The numbers of the pins of the microphone plug are shown in Fig.
soldering the wire to the pins, pre-tin the wire receptacle of each pin of the
ph.
4.
during the soldering operation, so that both hands are free to
5,
as viewed from the back of the plug. Before
\
RETAlNlNG
SCREW
CABLE
RETAINER ScREwQI
CLAMP
1
Page 17
Fig.
5.
Microphone plug pin numbers viewed from rear of pin receptacle
Be sure that the housing and the knurled ring of Fig.
-
the microphone cable before starting to solder. If the washer is not captive to
the pin receptacle body, make sure that it is placed on the threaded portion
of the pin receptacle body before soldering.
If the microphone jack is used to hold the pin receptacle
operation, best
first and then the connections to pins 2.and
made
of solder and be careful to prevent excessive solder accumulation on pins,
which could cause a short between the pin and the microphone plug housing.
6.
When al1 soldering connections to the pins of the microphone plug are com-
plete, push the knurled ring and the housing forward and screw the housing
ont0 the threaded portion of the pin receptacle body. Note the location of
the screw clearance
in the pin receptacle body. When the housing is completely threaded into the
pin receptacle body, a final fraction of a turn either clockwise or
clockwise may be required to align the screw hole with the threaded hole in
the pin receptacle. body. When
screwed into the place to secure the housing to the pin receptacle body.
7.
The two cable clamp retainer screws should now be tightened to secure the
housing to the microphone
followed, the cable clamp should secure to the insulating jacket of the microphone
cable.
8.
Upon completion of the microphone plug wiring, connect and secure the
microphone plug in the transceiver.
results are obtained when the connections to pins 1 and 3 are
hole in the plug housing with respect to the threaded hole
these are aligned, the retaining screw is then
cord. If the cutting directions have been carefully
3
are pushed back ont0
during the soldering
4.
Use a minimum amount
counter-
Page 18
-
A FEW FULES THAT SHOULD BE OBEYED
1.
You must identify your official licensed cal1 sign at the beginning and end of
every conversation.
2.
You are not ailowed 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.
7
3.
You are not ailowed to blast others off the air by over-powering them with
-
illegaliy amplified transmitter power, or illegally high antennas.