AKG Acoustics WMS 4000 - Manual (Page 23)

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AKG WMS MULTICHANNEL TECHNOLOGY
WMS frequency band with TV transmitter
If you are faced with interference caused by a television station, select the carrier frequency of the wireless microphone system such that there is a separation of at least 500 kHz from
the video carier, and 200 kHz from the audio carrier. Caution: changing a single carrier frequency may result in chaotic intermodulation in the entire multichannel system!
The Frequency Management Program from AKG provides a simple solu-tion to this problem as it automatically finds frequencies that wll not interfere with one another.
Intermodulation
The nonlinear characteristics of a transmission link may
cause intermodulation problems. Intermodulation produc-
ts do not increase linearly as f1 and f2 rise in amplitude
of, but significantly faster. 3rd order intermodulation arti-
facts are the biggest problem that beset wireless systems,
as they are strong enough to be clearly received.
Intermodulation
The simultaneous use of several radio sources results in
intermodulation products in the frequency spectrum. If, for
example, a third radio source (microphone) is used on the
same frequency as that of a 3rd order intermodulation pro-
duct of microphones A and B, microphone C is very likely
to pick up a lot of intermodulation noise. This is why it is
essential to test all the radio frequencies you wish to use
before each performance.
The Auto Setup function performs this text automatically.
6052_WMSKern_engl.qxd 01.03.2006 11:52 Uhr Seite 23