LAVALIERCONDENSER MICROPHONE MKH 124, MKH 125 T, MKH 126 P48

Introduction

The microphone part MK 12 is a Lavalier condenser microphone in RF- technique leaturing a diaphragm 01only 6 mm diameter. Corresponding to its use the microphone was designed as pressure transducer (omni- directional). Therelore, the MK 12 is very insensitive to handling noises. The complete microphone consists 01two parts, the miniature microphone and the electronic unit. MH 124, MH 125 T, MH 126 P 48 or the studio transmitter SK 1007 may be alternatively connected to the MK 12.

The prolongation between microphone and electronic unit is possible with connection cable MZV 125.

Technical Notes

High Frequency Circuit

The capsule 01 a RF condenser microphone presents, contrary to low Irequency circuits, a low impedance output. Instead 01the high polarization voltage normally required, a high Irequency capsule needs only a high Irequency voltage 01about 10 volts, which is produced by a built-in

~low noise oscillator (8 MHz). The low capsule impedance leads to a high performance reliability 01the microphones.

MK 12 + MH 124 = MKH 124

The MKH 124 is designed lor direct connection to the Microport- transmitter SK 1008-3. The power supply is provided by the transmitter.

MK 12 + MH 125 T = MKH 125 T

The MKH 125 T is designed lor AB-powering.

Senn heiser electronic introduced A-B powering, which was then standardised in DIN 45595. As with dynamic microphones, only two wires are required to connect the microphone when this powering system is being used. The operating current is led along the same wires as the audio Irequency signal, so that the circuitry in the microphone does not have to be connected to ground. Because 01these ground-Iree tech-

niques the highest possible values 01immunity lrom noise er disturbance are achieved.

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