Shure 444T User manual

222 HARTREY AVE.. EVANSTON. IL. 60204 U.S.A.
DATA MODEL 444~
El-
-
MICROPHONES AND ELECTRONIC COMPONENTS
SHEET
COMMUNICATIONS
Q AREA CODE 312/328-9000 .CABLE: SHUREMICRO MICROPHONE
TRANSISTORIZED BASE STATION WITH VARIABLE OUTPUT LEVEL
The Model 444T is specifically designed for Citizens
Band applications.
Features:
1. A Built-in, Two-transistor Preamplifier-with volume
control (red knob) to give variable high output from
the microphone-has self-contained battery.
2. High Output Level to Maintain Maximum Modula-
tion.
3. Response for Single Sideband Transmission.
4. Finger-Tip Control Bar
5. Long-Life Switch.
6. Adjustable Microphone Height.
7. A Sturdy, High Impact"Armo-Dur@" Base and Case.
8. Dependability - under all operating conditions.
Connections: Figure B shows internal wiring of the
Model 444T Microphone.
The Model 444T may be connected to an amplifier of
1,000 ohms input impedance or more. In this case the
white ("hot") lead and shield conductors are con-
nected to the microphone circuit. The black and red
conductor are used to control an external relay or
control circuit. The microphone as furnished is wired
for normal relay type switching. To modify for isolated
relay type or electronic type switching, remove bottom
plate from microphone base and proceed as follows:
-For isolated relay switching, clip the
blue lead
from the switch to the transistor preamplifier
board.
-For electronic swit.ching, leave the blue lead con-
nected, and clip the gray lead connecting the
normally closed blades of the switch.
To install battery proceed as follows:
1. Loosen two screws (located underneath base) hold-
ing battery retaining clip.
2. Remove battery-clip assembly.
3. Connect terminal strap to battery and insert battery
into retaining clip.
4. Reassemble battery-clip assembly into microphone
and tighten screws securely.
Press-to-Talk Switch Operation: The Finger-Tip Con-
trol Bar can be used in a locking or non-locking switch
action. To use as a non-locking switch, simply depress
the Control Bar and release after transmission. To
use as a locking switch, depress the Control Bar, move
forward by pulling with the finger tips; to unlock
switch, move Control Bar in a backward direction and
remove pressure from the bar.
Important: Shure Microphone Cables are selected
after exhaustive tests to insure superior performance
in microphones because of low capacities, superior
shielding properties and unusually long life under
severe use.
Cables with plastic insulation should not be sub-
jected to excessive soldering-iron heat. Carefully clean
and tin the conductors and the connections to which
the conductors are to be. soldered. The solderina
operation can then be done with a minimum of
heat
thereby avoiding any possibility of damage to the
cable.
Guarantee: This Shure product is guaranteed in normal
use to be free from electrical and mechanical defects
for a period of one year from the date of purchase.
Please retain proof of purchase date. This guarantee
includes all parts and labor.
Shipping Instructions: Carefully repack the unit and
return it prepaid to the factory. If outside the United
States, return the unit to your dealer or Authorized
Shure Service Center for repair. The unit will be
returned to you prepaid.
Copyright 1966, Shure Brothers Incorporated
27A672 (NB)
(OVER)
Printed in U.S.A.
U.S. Patent D-198,850

SPECIFICATIONS
Type:
Controlled Magnetic-with transistor preamplifier
Frequency Response:
200 to 6,000 Hz (See Figure A)
Polar Pattern:
Semidirectional
Output Impedance:
Less than 1,000 ohms
Output Level:
Adjustable from 2 mV to 45 mV for 1 microbar input
Battery Drain:
.7 mA
Battery Life:
Over 300 hours of operation-1 year maximum
Battery Type:
Eveready 216 or equivalent
Switch:
Press-to-Talk switch. Locking or non-locking oper-
ation-to operate microphone circuit or external
control circuit.
Cable:
Three-conductor (one conductor shielded), plastic
jacketed coiled cord, 1.5m
(5 ft) extended
Finish:
Gray
Dimensions:
See Figure C
Net Weight:
680 grams (1 Y2 Ib)
Shipping Weight:
964 grams (2% Ib)
FREQUENCY IN HERTZ
FREQUENCY RESPONSE
FIGURE A
SWITCH MOVEMENT BLACK
i;";& RED
WHITE
SHIELD
p
MICROPHONE
YELLOW
BOTTOM VIEW
INTERNAL CONNECTIONS
FIGURE B
6.Lmm(lll INITRAVEL
TO OPERATE SWITCH
OVERALL DIMENSIONS
FIGURE C