Induction loop

[ezzzekiel]

took my old man for his 6month hearing aid check up and although he worn one for a couple years now he still struggles with it, while in waiting room a leaflet on wall mentioned the induction loop which ive read something about in the onsite guide somewhere before.

anyways i know its for hearing impaired so was thinking of installing one, any1 any experience as ive never come accross it before.

 

[Sintra]

A current from a loop amplifier powers the cable. The amplifier gets its signal from a direct connection with another sound source. This can be, for example, a microphone placed in front of the person speaking or connection to an existing multi-media system ( PA system, laptop, DVD etc ). The resulting electric current in the Induction loop produces a magnetic field that matches the sound. You can then pick up this magnetic field if you are sitting within the area of the Induction loop and your hearing aid - or Induction loop listening aid - is switched to the 'T’ - telecoil setting. You can adjust your own hearing aid for volume in the usual way.

So basically you have to wire a loop of cable around permiter of room from amp plug it in and connect mic & set volumes.

 

[ezzzekiel]

sounds pretty straight forward - is it a coiled cable or sometype with good induction values?

 

[telepath]

Found some info on induction loops that may be of interest. Hope it helps.

Where can cable be placed?

Loops can be fixed at various heights dependant on type and use. The one height they must NEVER be fitted is at the same height as the hearing aid as this causes massive fluctuations in signal loudness across the width of the area.
Perimeter loops are ideally installed at a height of 14% of the loop width (shortest dimension), above or below the listening plane. The listening plane is normally (for a seated person) assumed to be at a height of 1.2m (ie ear level). This gives two possible loop wire installation heights – one above and the other below the listening plane. So the ideal install height could be in the basement, at floor level or high up the wall, all depending on room width. High level loops can be installed in plastic trunking or fixed to or behind wooden or other decorative features. The loop cable can even be run externally or directly buried if a suitable grade of cable is used.
Array systems are almost always installed on the floor or in plastic conduit above a suspended ceiling. This is because the loop wire runs backwards and forwards across the width of the room a number of times in a specific pattern often called an array. The physical dimensions of each array are quite critical in terms of wire placement and spacing. An installation accuracy of within 50mm or better can be important when following drawings supplied by Ampetronic for an array layout. Arrays can occasionally be fitted in plastic conduit in the top surface of a screed layer.
Installation along steps in tiered seating or similar requires careful thought. Take a look at some of our recommended installation methods for steps.

 

[ezzzekiel]

thnx good starting points

 

[Cj24]

Wat kind of area can you run your loop of say 1.5 twin or does it not matter or do you have to upgrade size of cable

 

[Sintra]

You wouldn'd use a 1.5mm twin for an induction loop.

 

[Golden_Boy]

Wat kind of area can you run your loop of say 1.5 twin or does it not matter or do you have to upgrade size of cable

Any type of wire can be used and almost any length.. The output impedance of a loop amp is abt. 1.5 Ohms but will feed down to ( almost ) zero ohms and still work.