GRAS 45AA Telephone Test Head
IEC 60318 or IEC 60711 depending on configuration
The GRAS 45AA Telephone Test Head is a tailor-made fixture for testing the acoustic performance of telephone handsets in accordance with international standards and recommendations. The design of the GRAS 45AA combines precision with a robust construction to ensure stability and reproducible test results with a minimum of acoustic interference.
Technology
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.
Speaking Position | Recommendation |
LRGP | ITU-T Rec. P76 |
AEN | ITU-T Rec. P76 |
HATS | ITU-T P58 |
REF | OREM A |
Anti-vibration Mounts
The GRAS 45AA stands on four anti-vibration mounts to isolate it from extraneous vibrations which could otherwise lead to spurious measurement results.
Handset Alignment
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.
Specifications
Ordering info
Included items
- |
4 different brackets for selecting direction of the Mouth Simulator |
Optional items
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
GRAS 44AA |
Mouth Simulator (with built-in amplifier) |
GRAS 44AB |
Mouth Simulator |
For test of the earpiece in the handset
GRAS 43AD |
Artificial Ear for Telephone Test Head (IEC 60318) |
GRAS 43AE |
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 RA0141 |
Reference Gauges |
GRAS Sound & Vibration reserves the right to change specifications and accessories without notice.