Page 1
Industrial Audio Products
Description
The Astatic Model 552 is a semidirectional, low impedance, dynamic
microphone designed to provide years of dependable service under punishing
conditions in any environment.
A versatile DPDT switching arrangenemt permits use in any communication
system.
The model 552 is sharply responsive to voice frequencies (see curve on
back side) and effectively reduces background noise.
The housing is virtually indestructable and is sealed against harmful or
corrosive vapors.
A heavy duty coiled cord with a molded strain relief to ensure long life,
extends safely to 1.8m (6 ft.)
Manufactured in the U.S.A. by Astatic, producers to quality microphones
since 1932.
552
DYNAMIC INDUSTRIAL MICROPHONE
Applications
P AGING: Excellent for close talking indoor or outdoor , especialy where
background noise, moisture, high temperatures, dust and corrosive vapors
are a problem. The tailored frequency response provides high intelligibility
even in the most critical situations. Ideal for steel mills, factories, warehouses,
engine rooms, airports, etc.
MOBILE COMMUNICATIONS: The ruggedness of the Model 552,
including a virtually indestructable housing and a heavy duty neoprene coil
cord, make it an excellent choice for trucks, motorcycles, helicopters, buses,
taxi cabs, trains, etc. The tailored frequency response is ideal for high
intelligibility and effectively reduces background noise.
Architects' And Engineers' Specifications
The microphone shall be an Astatic Model 552, or equivalent. It shall be a
dynamic type with a frequency response of 300 to 6500 Hz at low
impedance. The microphone shall have a semidirectional polar pattern.
The microphone shall provide high intelligibility and low background noise
pickup.
The output level shall be -58dB (0dB = 1 mw/10 microbars) at an impedance
of 400 ohms,
The microphone shall be fitted with a sealed, lever operated, push-to-talk
leaf switch with gold alloy contacts arranged in double pole, double throw
conformation so that when the switch lever is depressed both the auxilary
control circuit and the signal output are actuated.
It shall be equipped with heavy-duty black neoprene coiled cord, capable
of being extended to 1.8m (6') in length. The cable shall have two shielded
microphone conductors plus two relay conductors. A durable strain relief
bushing is to be provided to protect the cable at the microphone housing.
The microphone case shall be of "Derlin" or equivalent and shall be sealed
against the entrance of moisture or corrosive vapors by means of a suitable
seal between front and rear halves of the housing. Nevertheless, it should
be possible to open the housing, if necessary, and then reseal it using no
special tools. Similarly , it must be possible to remove the grille to clean beneath
it and then replace it without violating moisture proof qualities of the
microphone.
The microphone shall weigh approximately 424 grams (15 oz.), and should
not exceed 178mm x 51mm (7" x 2" x 2") in size.
Page 2
SPECIFICA TIONS FOR 552
CLEANING: Coin tightened screw facilitates easy grille removal. Rinse
gently in detergent solution or wipe with any thinner to clean housing or
isolating vane from accumulated dirt. Iron fillings can easily be removed
from vane with a magnet or a brush.
SWITCH ACTION: Grip-to-talk lever when depressed activates both the
microphone and control circuit. The microphone is assembled for non-locking
operation. Should locking action be desired, remove 5 screws at back of
microphone. Carefully remove rear housing. Remove red insert (see diagram
below) in switch bar slide cavity. Reassemble microphone carefully to assure
proper seal. To "lock on" microphone, move switch bar upwards from
depressed position.
TWO-YEAR LIMITED W ARRANTY
Omnitronics, LLC (“ASTATIC”) hereby warrants that this product will be free of defects in material
and workmanship for a period of two years from the date of purchase. In the unlikely event a defect
occurs AST ATIC will, at its option, either repair or replace with a new unit of equal or greater value.
Y ou should retain proof of purchase to validate the purchase date and return it with any warranty
claim. Return warranty claims carefully packed, insured and prepaid to the Service Department at
the address listed below.
This warranty excludes exterior finish or appearance, damage from abuse, misuse of the product, use
contrary to AST A TIC’ s instructions or unauthorized repair. All implied warranties or merchantability
or fitness for a particular purpose are hereby disclaimed and AST ATIC hereby disclaims liability for
incidental, special or consequential damages resulting from the use or unavailability of this product.
This warranty gives you specific legal rights and you may also have other rights which vary from
state to state. Some states do not allow the exclusion or limitation of incidental or consequential
damages or limitations on how long an implied warranty lasts, so the above exclusions and limitations
may not apply to you.
Note: No other warranty, written or oral is authorized by Omnitronics, LLC
Loading...