Install a home loop system?
Steve
listening or whatever?
====================
Excerpts from
http://www.audiologyonline.com/articles/arc_disp.asp?id=1423
Staying in the Loop: When Hearing Aids Are Not Enough, by Christine G.
Diles, Au.D., & William S. Diles, M.A.
Loop systems are not just for public places anymore. Background noise,
distance, and reverberation are no longer a problem.
Room loops for residential applications do not require special
considerations and installation can be done without a professional.
Most installations take less than one hour, and once installed, loop
systems are virtually maintenance free.
There are no audiometric contraindications regarding loop
recommendation or usage. Individuals with any type and degree of
hearing loss, and any t-coil equipped hearing aids, can benefit from
loop technology.
Patients with poor word recognition scores are often well-suited for
loop technology due to the advantageous signal-to-noise ratio when
listening through the loop. Patients typically report greater speech
intelligibility while using a home loop system than they obtain with
their hearing aids alone.
While there are several loop systems available, the loop system we use
is the recently introduced Field, available from Phonic Ear of
Petaluma, California. The Field comes complete with amplifier,
microphone, power supply, and 135 feet of wire, to cover an area of
approximately 30x30 ft. The Field is equipped with dual AGC functions
and volume and tone controls. It costs $205 for the hardware.
For more information on induction loops: www.hearingloop.org
For more information about our home loop installation program:
www.goodhearing.com
For more information about Phonic Ear: www.phonicear.com
helco
"Steve" <d...@tye.inv> wrote in message
news:tbumg1hqpda5fnakf...@4ax.com...
things: http://www.hearinglosshelp.com/
Helen
Ken
described how to make one yourself.
Ken
2. OORAH Apr 24 2003, 12:55 am show options
Newsgroups: alt.support.hearing-loss
From: O...@USMC.ret - Find messages by this author
Date: Wed, 23 Apr 2003 14:58:39 GMT
Local: Thurs, Apr 24 2003 12:58 am
Subject: Re: Do-it-yourself loop
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ken kerrison wrote:
> I, and no doubt others, would like to hear more about experiments with
> homemade loops.
Okay, I'll amplify. 8^)
The objective is an inductive loop - a winding of wire through which an
audio
signal passes, which creates a field within which the audio signal can
be
detected by appropriate equipment (i.e. telecoil). It is very much a
radio
transmitter and receiver, though at audio frequencies rather than the
AM or FM
bands.
1. Examine the amplifier. It should have a MONO mode. The output
connectors
(where the speakers would normally be connected) should say 4 OHMS or 8
OHMS.
That's important.
2. Buy INSULATED wire as follows:
18 gauge lamp cord is 0.0066 ohms per foot. 4 OHMS = 606'
20 gauge wire is .011 ohms per foot. 4 OHMS = 364'
22 gauge wire is .017 ohms per foot. 4 OHMS = 235'
2. Pick a path around the room on the ceiling, or under the carpet. A
room
measuring 15' x 20' will have a perimeter of 70', which will require a
minimum of
four complete turns of 22 gauge wire, six turns of 20 gauge wire, or
nine turns
of 18 gauge wire.
3. Pick a path around the room near the ceiling, and wind (or hang)
your "coil",
or loop, starting and ending at the amplifier.
4. Connect either end of the wire to the + terminal (red, usually) and
the other
end to the - terminal (black). Most amps have SPEAKER A and B switches;
put this
circuit on the unused one.
5. Turn on the music. Set the amp to MONO, and select the appropriate
speaker
circuit. Switch the aid to telecoil. Experiment with locations in the
room. Enjoy
(hopefully).
NOTES:
If the back of your amplifier says something like "8 OHMS MINIMUM",
double the
required wire length (load).
Buy 120% of the wire you'll need to ensure that you can complete the
loop.
You can add a POWER RESISTOR (Radio Shack, surplus, etc.) to ensure an
appropriate load and reduce wire length, but the amplifier output will
be divided
between the loop and the resistor, proportionately, which means less
radiated
energy. This solution requires a LOT of energy so try not to
compromise. If
required, get 4 OHMS at 10W minimum.
There's another and simpler approach: I have a coil built into my
favorite chair.
It's only 18" in diameter, but includes 120' of 28 gauge wire (0.071
OHMS per
foot). That's about 25 turns of that relatively thin wire - easy to do,
flexible,
etc.
If you're happy with the result but annoyed by the LOW-FI effect, have
your
audiologist expand the bandwidth of the telecoil setting of your aid.
It is
probably set to the very narrow frequency range of a telephone rather
than the
broader range of music, etc.
There's strong 60 cycle (Hz) noise in your home from the house wiring.
It may
interfere.
Last point: if you worry about the radiated energy, get a tinfoil hat.
Mike
could be used, placed at 90 degrees to each other with the user in the
middle of both. Only hard part would be that the telecoils would also
have to be oriented similarly.
Mike
Steve B.
Plastic surgery?
Steve = ; ^ )
in...@fairbankharding.com
Interesting information on Induction Loop systems and they even have a
'package' called a domestic loop system to enable you to hook up a TV
and even your doorbell.
in...@fairbankharding.com
Gary G
Mike
Exactly : )
Mike