TELA - Telephone-Interface

TELA very easily realizes a link between the telephone system and the PA system and enables the telephone announcements into the PA system.

Applications for use of TELA can be found wherever voice messaging needs to be routed into the PA system by telephone as an alternative for a paging station. TELA eliminates the need for long cabling connections of paging stations, allowing different buildings to be interconnected cost efficiently.

The level of the phone call and listening level can be adjusted. A sound signal indicates when TELA is connected to the PA system ; a ‘busy’ signal indicates active calls. By entering a key code combination, access by unauthorized users can be prevented.


Impedance analyzer for the measurement in the range of 25Hz to 25kHz. Conventional impedance analyzer for PA systems usually work with a frequency of 1 kHz only. However, the majority of PA system providers, including GRÄF & MEYER, use the so-called pilot tone measurement method, which operate with a non-audible frequency of 22kHz.

For this measurement method, the impedance of the speaker line plays an important role. The impedance or ‘watt’ specification of the loudspeakers is usually specified by the loudspeaker manufacturers at 1kHz, while at 20kHz, most loudspeakers have a higher impedance. Therefore, the capacity of a loudspeaker line at 20kHz cannot be ignored. In general, if the 20kHz pilot tone is applied to the output permanently, an overload of the connected amplifier cannot be prevented.

Only when the impedance of the loudspeakers is known at 20kHz and is compared with the impedance of the line, fault detection can be ensured.
In order to be able to install and maintain PA systems, in accordance with current standards, the ANALYZER MK1 should be a standard tool for every specialist, planner or technician.

ANALYZER MK1 - Protective Carrying Bag - optional.

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More informationen:

Ringstraße 1
D-66459 Kirkel

Fon: +49 (0) 6841 / 934 93-0
Fax: +49 (0) 6841 / 934 93-10






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