Hearing Aid Compatibility (HAC)

Many seniors phones today offer the possibility to use weiterlesen

Many seniors phones today offer the possibility to use the phones in conjunction with hearing aids. For this, the telephone handset with hearing aid compatible technology equipped. Basically, there are two types of hearing aids support.
Firstly, the acoustic matching, that means the speaker of the handset and the design of the receiver housing is constructed so that ambient noise shielded from the hearing aid and thus not from the hearing aid with be strengthened. Furthermore, the telephone handset and speaker and microphone in the handset are designed so that any feedback on the hearing aid can be largely avoided. These measures ensure already significantly improved voice communications in conjunction with a hearing aid.
In addition to the design-related and acoustic adaptation of the telephone receiver to hearing aids, there is the compatibility with hearing aids in the form of the inductive coupling.
This means that the telephone receiver is equipped with a speaker in addition to the electromagnetic coil. Hearing aids which also has a coil, have a so-called inductive coupler can now generate about electromagnetic induction speech signals directly in the hearing aid.
Since only the voice signals are transmitted through the telephone handset by electromagnetic induction, it thus no distracting background noise completely. It should be noted that both the phone as well as the hearing aid in the T-mode (telecoil mode) are operated.
There is also the possibility that the feature is not automatically available, but that it must be set manually.

In the United States has existed for several years a standard for the classification of hearing aid compatibility.
Here is the classification of M1 to M4 for devices which operate on the principle of the acoustic coupling.
M4 stands for the best HAC classification with acoustic transmission. The classification T3 and T4 refer to inductive coupling.
T4 is also the best possible classification for these transmission technology.

Why still ISDN?

Some years ago, ISDN was used predominantly as a stable weiterlesen

Some years ago, ISDN was used predominantly as a stable and for that time faster Internet access. Today, for most users is the convenient, professional landline communication. According to the annual report of the Federal Network Agency of 2011, there are still around 11 million ISDN lines which, commercial, medical practices and law firms are mainly used in the private sphere or in the areas of Small Office

And with good reason, because there is hardly a technology with which you can create the necessary communication solution as simple and flexible as with an ISDN connection. Thus, the user has 2 call channels available which can be used simultaneously. Furthermore, the user can manage and assign multiple phone numbers free.

Features such as caller number display (CLIP) or convenient call forwarding are as much features as call waiting, toggling or conference call, the network functions.

While in the past mostly ISDN Telefonanalgen used, sat down today, more and more wireless DECT systems by. This can be connected without any installation effort directly at the transfer point of the Telekom the NT. The available numbers (MSN = Multiple Subscriber Number) can be distributed to the registered to the base station handsets as needed. This allows individual handsets are selected specifically by external participants.

This allows for ideal communication solutions such as for multi-generational households, or should if possible to distinguish between private and business calls

Also, from a cost perspective, the ISDN connection points, as is the additional monthly cost to an Internet telephony and complete package of Deutsche Telekom, a so-called "Call & Surf" tariff only 4 per month compared to a standard analog phone line. The significantly larger scope of work and the resulting use of opportunities at a manageable cost more to make the ISDN connection is still attractive.

How can I use the handsfree in my car with the phone?

Many vehicles today are factory-equipped with a hands-free [...]


Many vehicles today are factory-equipped with a hands-free system. To use this, usually a mobile phone with Bluetooth interface is needed
Bluetooth is a special type of short-range radio which allows for a very short distance data transfer between two devices. Data can, for example, this Pictures, address data, audio files, videos but also language in the sense of a call.
Depending on the application and device used, set the units communicate with different Bluetooth profiles.
The simplest form of a hands-free application is the use of a wireless Bluetooth headsets, this, the mobile phone must support the Headset profile (HSP).
For easy hands-free calling in the car a lot of hands-free systems use the Handsfree Profile (HFP).
This profile supports only the conversation and answering and ending a telephone call via the hands-free system.

Many vehicles, however, are already equipped with comfortable hands-free systems, which for example represent the entries in the phone book are displayed on the board computer in the vehicle, so you can choose easily by pressing a button. This, however, you need the SIM Access Profile (SAP, or even because of rSAP engl. Remote) which provides access to the SIM card in the mobile phone.

When SAP profiles, the phone gives all the information on the SIM card to the speakerphone on, so that the subscriber can log in using the speakerphone in the mobile network. To this end accesses the carkit is sent through the Bluetooth connection on the SIM card of the phone.

Even more convenient, does the dial by voice control. With a push button voice control of the handsfree system is activated, the driver now speaks the name or the number that he wants to call and the system automatically decides the number stored in the phone book under the appropriate name. For this comfort handsfree systems Bluetooth profiles like HFP (Hands-free Profile) are used

There are now over 20 different, some manufacturer specific Bluetooth profiles. To ensure that mobile phone which feature works with the particular hands-free system in a vehicle, it is necessary to inform you that is supported Bluetooth profile of the respective free system. The appendix contains a reference list of our mobile phones with a list of which will be provided from the corresponding device Bluetooth profiles.


Bluetoothprofile (PDF)