Shure 104C - Manual

HAND-HELD CARBON MICROPHONE

GENERAL

The Shure Model 104C is a small, pressure–actuated, dia-

phragm–type, carbon microphone specially designed for

clear, efficient speech reproduction. The 104C fits naturally

and comfortably in the hand, and retains this feel in hot or

cold weather. The sturdy, high–impact ARMO–DUR



case

is light and compact, and occupies minimal space in portable

or mobile equipment.

The 104C is equipped with a heavy-duty, push-to-talk

switch and a long life, rubber-jacketed coil cord cable.

Features:

•

Frequency response from 300 to 4,000 Hz, specifically

designed for voice communications use

•

Small, light and compact case, takes minimum space in

portable and mobile equipment, fits comfortably and

firmly in the hand

•

Extremely rugged, high-impact ARMO-DUR



case,

stronger and lighter than die-cast metal, comfortable to

the touch in hot or cold weather

•

Double-pole, single-throw, leaf-type switch designed to

stand up under rigorous operating conditions and

constant usage

•

Long life, rubber-jacketed coil cord

•

Rugged and dependable under all operating conditions

APPLICATIONS

The Model 104C is especially recommended for all types

of outdoor and indoor communication activity: in mobile and

fixed station use (as in police, fire, utility, forestry and trans-

portation services), and in commercial and industrial ap-

plications—including radiotelephone, amateur radio and

similar uses. The microphone is also suitable for voice ap-

plications in indoor and outdoor public address.

The Model 104C will operate satisfactorily under most

conditions of temperature and humidity.

The Model 104C is a replacement for Shure Model 101C,

101E, 102C, 102E, 104A and 1048 Carbon Microphones.

INSTALLATION AND CONNECTIONS

A mounting bracket for permanent installation is sup–

plied with the Model 104C (see Figure 1).

46 mm

36.5 mm

4.7 mm

34.5 mm

10.3 mm

9.5 mm

9.1 mm

(23/64 IN.)

(3/8 IN.)

(1-13/16 IN.)

(1-7/16 IN.)

(3/16 IN.)

(1-23/64 IN.)

(13/32 IN.)

MOUNTING HOLES,

CLEARANCE FOR

No. 8 SCREWS

MOUNTING BRACKET

FIGURE 1

The internal switch connections of the Model 104C are

shown in Figure 2. The Model 104C has a double-pole,

single-throw, normally open, leaf-type switch to control the

microphone and relay or switching circuits.

The Model 104C has a four-conductor coiled-cord cable:

The RED and BLACK leads are the microphone circuit, and

the GREEN and WHITE leads are for connection to the relay

or switching circuit.

A typical operating circuit using the Model 104C is shown

in Figure 3. The voltages (E) and corresponding resistances

required to limit the operating current through the carbon

cartridge to approximately 50 mA are as follows:

E (Volts)

Total Minimum Circuit

Resistance (ohms)

4.5

50

6

100

12

200

24

500

Note that the resistance value includes both resistance R

in the figure plus other dc circuit resistance (transformer pri-

mary, etc.). The Model 104C will operate satisfactorily with

current up to 50 mA. However, no damage will result if the

current rises to 100 mA. The resistance of the carbon car-

tridge is 30 ohms with 50 mA flowing through the cartridge.

Model 104C Guide

27

C

1149 (Rev.

4

)



200

5

, Shure Incorporated

Printed in U.S.A.