PAGING MICROPHONE MODEL CSM660 DATA SHEET Rev 2.0
GENERAL DESCRIPTION
The paging microphone is of the desktop type and designed to be used for paging and announcements. It is
furnished with an easy to use talk switch and a convenient locking lever. In addition, the unit provides a
remote-control function to activate the amplifier's "claim" or chime function. Refer to your amplifier's
instruction manual for details of the available functions and connections.
CIRCUIT DIAGRAM
A
PPEARANCE
The microphone is supplied with a 5-pin DIN style connector pre-fitted.
This allows direct connection to the AVS AVU2001 or AVU2002 pre-
amplifier/line-driver units.
If required, this plug may be removed, and a different connector fitted.
Most preamplifiers or mixer amplifiers typically require a 3-pin, XLR
type plug, or a 3-pole 6.3mm (1/4”) jack plug.
The wiring for these types of connector is shown below.
HOT = MICROPHONE “HOT” WIRE
COM = MICROPHONE SCREEN WIRE
COLD = MICROPHONE “COLD” WIRE
NOTE the drawing of the ¼” JACK plug (below left) shows the elements of the connector. As the actual
internal terminals frequently differ from one manufacturer to another, you should use an ohm-meter to
establish which terminal of the plug is connected to which element (Tip, Ring and Sleeve).
NOTE the drawing of the XLR plug (below right) shows the REAR of the plug (the wiring side). Use pin
numbers as a reference, as plug pins and socket pins have their positions reversed. Refer to your amplifier's
instruction manual for details of the required connections
Typical 3-pin XLR Plug
Typical 6.3mm Jack Plug
HOT
1
3
COLD HOT SCREEN
COLD
SCREEN
2
DOCUMENT NUMBER AVS/CSM660/OEM/01 REV 2.0 25
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As you can see from the circuit diagram, the microphones’ capsule is short-circuited by one half of the push-
to-talk switch. This means that the output wires (White & Red) are a short-circuit when the PTT switch is not
pressed, thus preventing any signal at all reaching the amplifier.
When the PTT switch is pressed, this short-circuit is removed, and the audio from the microphone capsule is
fed into the amplifiers’ input. At the same time, the second half of the PTT switch places a short-circuit
across the Blue & Black wires and these may be used to trigger an external action e.g. the “Chime” in a local
device, such as the AVU2002 pre-amplifier/line driver.
IMPORTANT SAFETY NOTICE :-
For safety reasons, the shield (or screen) of the microphone cable must be earthed at the equipment end.
Most equipment with microphone inputs has its’ chassis at earth potential, but some (typically low-voltage
supplied devices) may not. It is the installers’ responsibility to ensure that the microphone is
adequately earthed!
TECHNICAL SPECIFICATIONS
MODEL CSM660B
TYPE Moving Coil Microphone
Polar Pattern Unidirectional
Impedance 600 Ohms, Balanced
Sensitivity -58db @1 KHz (0db = 1V Pa)
Frequency Response 100Hz-10KHz
Connection Cable 2 core shielded + 2 core cable
Cable Length 2.5m (8 ft 2 ins)
Terminal Connector 5 Pin DIN Plug
Weight * 440 g (0.97 lb)
Dimensions 100 (W) X 215 (H) X 150 (D) mm (3.9 X 8.5 X 5.9 Ins)
Talk Switch Push-to-Talk (Short off circuit, with locking lever)
Remote Switch Leaf Spring Contact (Interlocked with Talk Switch)
Finish HEAD : Zinc Plated Steel Wire, Baked Paint (Grey)
BODY : ABS Resin (Grey)
* Weight given in the above table does not include the connection cable or plug.
DOCUMENT NUMBER AVS/CSM660/OEM/01 REV 2.0 25
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