When used with GRAS 43AD articitial ear or GRAS 43AE IEC 60711 ear simulator, and a GRAS 44AA/GRAS 44AB mouth simulator, it can be set up for testing telephone handsets in accordance with ITU-T recommendations.
Positioning of the mouth
Four different, detachable precision brackets are provided for mounting the Mouth Simulator according to the standardised positions shown in the table for speaking into a telephone. These positions are maintained to within an accuracy of 1 mm. Reference gauges are available for verifying this.
|LRGP||ITU-T Rec. P76|
|AEN||ITU-T Rec. P76|
The GRAS 45AA stands on four anti-vibration mounts to isolate it from extraneous vibrations which could otherwise lead to spurious measurement results.
The GRAS 45AA is provided with graduated guides and stops for aligning a telephone handset correctly in position over the Artificial Ear. Lateral guides are independently adjustable to cater for asymmetrical handsets.
Once aligned, an adjustable spring-loaded, padded clamp will hold the handset in position. As specified in some tests, an adjustable force may also be applied by adding a small mass to the measurement object.
4 different brackets for selecting direction of the Mouth Simulator
Notice that for creating a complete order list you need to find relevant accessories for the chosen
GRAS 44AA, 44AB, 43AD and 43AE products. See www.gras.dk.
For test of the microphone in the handset
Mouth Simulator (with built-in amplifier)
For test of the earpiece in the handset
Artificial Ear for Telephone Test Head (IEC 60318)
Ear Simulator (IEC 60318-4). Includes GRAS RA0056 Low-Leak Pinna Simulator & RA0057 High-Leak Pinna Simulator
For verifying the position (AEN & REF) of the Mouth Simulator
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.