If the micraphone spacing is increased, (or if loudness is reduced), It will be necessary to advance the control ac- cordingly, while loud speech or a reduction in micraphone distance requires a lower setting. To facilitate precise matching of the system in studio operation, it should be mentioned that

correct adjustment of the sensitivity control is obtained when the audio

output of the receiver supplies + 6 db (1.55 volts) at modulation peaks.

3.2Microphones

In operating the micraphones it is merely necessary to note that directional types (MD 4008, MD 405-T, MKH 404 and MKH 804) should be pointed directly at the sound source wherever possible, since they are naturally less

sensitive to sounds coming from the sides and rear.

3.3Receiver Model EM 1008

The receiver is switched on by depressing the "ON" push button. In battery operation it is also advisable to depress the "battery test" push button to determine whether the pointer deflects weil into the red range of the indicating

instrument, indicating an adequate re- serve. The same channel selected on

the transmitter must be selected by

depressing the appropriate button on the receiver. As soon as the transmitter

is switched on, the instrument will show the fjeld strength. The pointer must

come to rest in the green section, indicating an adequate signal is present. Advancing the volume control enables the transmitted signal to be monitored by means of the built-in loudspeaker.

This output signal is available for feeding amplifier or tape recorder systems having a standard studio input level of 1.5 V (+ 6 db). To prevent noise being transmitted to the amplifiers or tape recorder systems when the transmitter is off, the 'squelch'control should be adjusted by turning it slowly clockwise, starting fram position 1, until

the meter needle jumps into the blue field. When the transmitter is switched

on, the squelch relay will be activated and the meter will show fjeld strength. When the automatic squelch feature is not required, the squelch contra I can be lett at position 1. In order to reliably

check operation it is advisable to switch on the transmitter and walk over the

entire transmission area while a second person observes the field strength indi- cation. Excessively low antenna voltage, indicated by a pointer on the lett-hand side of the scale may be impraved by reorienting the antenna.

4. Special situations

4.1Diversity reception

For particularly important applications, where not even the slightest temporary reduction of transmission quality can be tolerated, it is possible for two or

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