222 HARTREY AVE.. EVANSTON. IL. 60204 U.S.A.
DATA
MODEL
CB42
@
AREA
CODE 312/328-9000
.
CABLE:
SHUREMICRO
SHEET
i
CONTROLLED MAGNETICa CITIZENS BAND MICROPHONE
GENERAL
The Model CB42 LONG RANGER CONTROLLED
MAGNETIC microphone is designed especially for use
with Citizens Bandtransceivers ineither mobile or base
stations. For clearer transmission and improved relia-
bility, this small, rugged, dual-impedance microphone
can be used to replace ceramic or dynamic micro-
phones supplied as original equipment.
Model CB42 provides crisp, undistorted voice re-
sponse of high intelligibility and high output. Easy
impedance selection at the end of the cable makes the
microphone suitable for connection to either high-im-
pedanceorlow-impedance(ceramicor dynamic) inputs.
The microphone fits naturally and comfortably in the
hand and is not affected by heat or humidity. The ex-
clusive ARMO-DURD case is immune to oil, grease,
fumes, salt spray, sun, rust, and corrosion-and is out-
standing in its ability to resist mechanical shocks
and vibration. It is designed to withstand rigorous
operating conditions and constant use.
Microphone Features:
Highly intelligible voice response
Replaces either ceramic or dynamic original equip-
ment microphones
Dual impedance-matches either high- or low-
impedance inputs
Reliable high output CONTROLLED MAGNETIC
cartridge
Unparalleled ruggedness and durability
Tough ARMO-DUR case
Mounting bracket supplied-fits hang-up button on
back of microphone
CONNECTIONS
The internal connections of Model CB42 are shown
in
Figure
1.
INTERNAL
CONNECTIONS
FIGURE
1
Refer to the Shure CB Wiring Guide enclosed with
the microphone for detailed instructions for connect-
ing the CB42 to your transceiver. If your unit is not
listed in the Guide, contact your dealer or Shure
Brothers Incorporated for information. This micro-
phone is not designed for use with transceivers requir-
ing five-conductor shielded cable. Passage of the CB42
cable through small-diameter connectors may be eased
by lubricating the outer jacket of the cable.
The general wiring procedure for transceiver con-
nections is as follows.
Relay or Switching Circuit:
GROUNDED SWITCHING
Most transceivers employ a grounded circuit to
switch from the receive to the transmit position. To
connect the microphone to such a circuit, proceed as
follows.
1.
Connect the RED lead to the terminal used to
complete the transmitter circuit.
2. Connect the BLACK lead to the terminal used to
complete the receiver circuit. This will usually be
a ground return from the loudspeaker. If a micro-
phone switching contact is not required for the
loudspeaker ground, insulate (wrap with tape)
the BLACK cable lead.
3.
Connect the shield to chassis or circuit ground
of the transceiver (see Guide).
ISOLATED SWITCHING
In some transceivers, an isolated circuit is required
to switch power supply voltages rather than grounds.
If an isolated switching circuit is required, proceed as
follows.
1.
With microphone grille side down on a flat sur-
face, remove the four No.
5
screws from the back
of the microphone case; separate the case front
and back. CAUTION: Microphone case is spring-
loaded; care must be taken to hold the two
halves of the microphone case together to retain
springs in proper position.
2. Clip and remove the GRAY lead connecting
switch terminals 2 and
5
(see Figure
1).
3.
Unsolder the BLACK cable lead from switch ter-
minal
3;
solder the BLACK cable lead to switch
terminal 2.
4. Fasten the two case halves together with the
previously removed screws.
Copyright
1976,
Shure Brothers Inc.
27A1319
(PH)
(OVER)
Printed in
U.S.A.
