Shure 407A Datasheet

CONTROLLED MAGNETIC@ HAND MICROPHONES
222 HARTREY AVE.. EVANSTON, IL. 6 0 2 0 4 U.S.A.
8
AREA CODE 3 1 2 / 8 6 6 - 2 2 0 0
.
CABLE: SHUREMICRO
TWX: 910.231-0048 TELEX: 72.4381
GENERAL
The 407 series of microphones are high-quality, ex-
tremely reliable hand-held CONTROLLED MAGNETIC@
microphones designed for clear, crisp, natural voice
response of high intelligibility. This series of micro-
phones features professional design, small size, light
weight, and modular construction, providing extreme
dependability and exceptional ease of field service.
The modular construction of the 407's accounts for
their tremendous ease of field serviceability. The car-
tridge, switch, and cable are of modular design which
makes them replaceable in a matter of minutes if re-
placement is ever necessary.
The unit fits naturally and comfortably in the hand
and is not affected by heat or humidity. Exclusive
ARMO-DUR@ case is immune to oil, grease, fumes,
salt spray, sun, rust and corrosion-and is outstanding
in its ability to withstand mechanical shocks and vibra-
tion. "Million-Cycle" leaf-type switch is double-pole,
single-throw, designed to withstand severe operating
conditions and constant usage.
Microphone Features:
Highly intelligible voice response
Unparalleled ruggedness and reliability
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CONTROLLED MAGNETIC@ element
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ARMO-DURe case
"Million-Cycle" leaf-type switch controlling
microphone and external relay or switching
circuits
Modular construction
Exceptional ease of field service
Life-time hang-up button and mounting bracket
TRIPLE FLEX@ cable provides 3 to 4 times the
flex life of any previously available coiled cords
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another Shure first
APPLICATION
The Model 407A and 407B microphones are highly
recommended for all types of mobile communications;
for hams; industrial and commercial paging; outdoor
public address systems; and all applications where a
rugged hand microphone is required. The Model 407A
is a high-impedance microphone with high output
level, making it suitable for public address amplifier
installations where a cable length of 15.2m (50 ft) or
less is needed. The Model 407B is a low-impedance
microphone and is recommended where long cable
lengths are required. The 407A and 407B are both
suited for use with transistor or vacuum tube ampli-
fiers, the 407A for amplifiers with high-impedance
DATA
SHEET
MODELS 407A and 4078
Copyright 1981, Shure Brothers Inc.
27A972 (AF)
A
inputs, the 4078 for amplifiers with low-impedance in-
puts.
INSTALLATION AND CONNECTIONS
A mounting bracket for permanent installation is
supplied with each microphone. (See Figure 1)
MOUNTING HOLES,
CLEARANCE FOR
No. 8 SCREWS
7
10.2 rnrn
(13/32 IN.)
MOUNTING BRACKET
FIGURE 1
The internal switch connections of Models 407A
and 407B are shown in Figure 2.
The Model 407A is a high-impedance microphone
with a three-conductor coiled-cord cable (one con-
ductor shielded) and a double-pole single-throw leaf-
type switch to control the microphone circuit and an
external relay or switching circuit. The RED lead is
the "hot" conductor for connection to the microphone
circuit; the shield is connected to the microphone
circuit ground. The NATURAL and BLACK leads con-
trol the relay or switching circuit. The microphone
circuit of the switch is normally shorted but may be
easily modified for normally open operation.
The Model 407B is a low-impedance microphone
with a four-conductor coiled-cord cable (two con-
ductors shielded) and a double-pole single-throw leaf-
type switch to control the microphone circuit and an
external relay or switching circuit. The WHITE and
GREEN leads are the "hot" conductors for balanced-
line connection to the microphone circuit; the shield
is connected to the microphone circuit ground. The
RED and BLACK leads control the relay or switching
circuit. The microphone circuit of the switch is nor-
mally open but may be easily modified for normally
shorted operation.
Modification of Microphone Circuit
The microphone circuit of the Model 407A is shorted
when the microphone switch button is in the normal
position. The microphone section of the switch has an
extra leaf which may be used in modifying the Model
407A to have a normally open microphone circuit. To
modify the Model 407A for a normally open microphone
circuit, proceed as follows:
1. Remove the three No. 6 Phillips self-threading
screws from the back of the microphone case.
2. Separate the case front and back and remove the
microphone switch button.
3. Unsolder or clip the RED cable lead from the
lower switch solder lug. (See Figures 2 and 3)
4. Solder this RED cable lead to the upper unused
terminal lug. (See Figures 2 and 3)
NOTE: In certain instances, if the switch sequence
is critical, it may be necessary to remove the
effect of the shorted switch on the cartridge. This
can be done by insulating the blade of the switch
with the BLACK wire and shield attached, from
the blade of the switch with RED wire attached.
This can be done by sliding a piece of "spaghetti"
Printed in U.S.A.