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REPLACEMENT COMPONENTS
Dynamic Cartridge........................................... Model R55
Switch .........................................................Model RK32S
Cable and Plug Assembly ................................ Model C55
INSTALLATION AND CONNECTION OF SWITCH
A. To install the RK32S Replacement Switch in the
Shure Model 55SW, proceed as follows:
1. Remove the two No. 2-56 screws holding the
nameplate and cover to the connector assembly.
2. Remove the nameplate and take switch out of
the switch cover on connector assembly.
3. Unsolder leads from old switch terminals.
4. Connect the leads to the new replacement
switch. Observe lead color and terminal ar-
rangements as in Figure A.
5. Re-assemble switch and nameplate back into
the connector assembly and fasten the No. 2-56
screws securely.
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 soldering
operation can then be done with a minimum of heat,
thereby avoiding any possibility of damage to the
cable.
SPECIFICATIONS
Type:
Dynamic
Frequency Response:
50
to 15,000 Hz. See Figure B.
Polar Pattern:
Cardioid (Unidirectional) Response at rear down 15
db from front. See Figure C.
Microphone Rating Impedance:
Equipped with multi-impedance switch, furnishing
a choice of 3 impedances: “L” for connections into
microphone inputs rated at 25 to 50 ohms; “M” for
connections into microphone inputs rated at 150 to
250 ohms; and “H” for connections into high im-
pedance microphone inputs.
Output Level:
1,000 Hz. response
Models 55S and 55SW “L” Position
Open Circuit Voltage Level.......
-
83.0 db* (0.071 mv)
Loaded with 50 ohms...............
-
87.5 db*
Power Level into 50 ohms ........ - 55.5 db**
EIA Microphone Rating
Gm (Sensitivity) ................. -148.0 db***
Models 55S and 55SW “M” Position
Open Circuit Voltage Level....... - 77.0 db* (0.141 mv)
Loaded with 250 ohms .............
-
81.0 db*
Power Level into 250 ohms ...... - 56.5 db**
EIA Microphone Rating
Gm (Sensitivity) ................. -148.5 db***
Models 55S and 55SW “H” Position
Open Circuit Voltage Level....... - 55.5 db* (1.68 mv)
Loaded with 100,000 ohms ...... - 57.5 db*
EIA Microphone Rating
Gm (Sensitivity) ................. -151.5 db***
* 0 db = 1 volt per microbar
** 0 db = 1 milliwatt with 10 microbars
*** 0 db = EIA Standard SE-105, August 1949
Cable:
15 foot (4.6 m) two-conductor shielded with Amphe-
nol MC3M type microphone plug on the microphone
end.
Case:
Chrome-plated die cast.
Dimensions:
See
Figure D.
Switch:
Model 55S None
Model 55SW Built-in “ON-OFF” switch to control
microphone circuit. The switch is an integral part
of the receptacle assembly and is a slide-to-talk
locking type switch.
Net Weight (Less Cable):
1
5
/
8
pounds (736 grams)
Packaged Weight:
3
1
/
8
pounds (1,417 grams)