Using a Test box

The FM Quality Standards sets the standards for good Radio Aid fitting and setting up.  QS3 states ‘the personal radio aid must be set up with the child’s individual hearing aids or implants to ensure that the radio signal provides the desired advantage’.

A test box or hearing aid analyser is a means of analysing the output and performance of the hearing device, both with and without the radio aid.  This is done by putting the hearing device along with the radio aid through the test box; you can print off the graph as a visual record.  It is therefore a means of seeing the effect of the additional device and ensuring that the performance of the hearing device is not altered and that the child gets the maximum benefit from using the 2 together.  The test box will give you the ability to print off a visual record of what the two systems are doing together.

The performance of radio aids and hearing aids can be measured and recorded over time.  This is in accordance with MCHAS protocols.  Examples of portable test boxes used by deaf professionals in the UK  are Frye Fonix FP35 or the newer Aurical HIT hearing aid test box.

The Ewing Foundation have produced some videos demonstrating the use of the FP35 test box.

There may some some differences in using the test box with different devices.

The Good Practice Guide produced by the FM Working Group, explains and expands the Quality Standards. Scroll down the page to find the Good Practice Guide. Section 8 is concerned with Electro acoustic checks.