Talk:Deaf Communications Device

Untitled
There are many communications devices for deaf people. The telecommunication Devices are only a small part of deaf communications. There are non telecommunications devices that have nothing to do with the telephone or the Internet. As deaf people, we actually communicate person to person and I can not use a TDD to talk to you in person can I?

Generic Names of Devices
Many devices made for deaf communications are only known by brand names. To avoid violating Wiki rules or advertising any ones product, those names will not be posted. One device has a name that only exists in sign language with no direct english translation. That device has no current manufacturer. If a device has a generic name or non brand name, it will be posted.

Devices for use one on one
There is a device that comes in pairs and has two keyboards with displays. Whatever is typed on one keyboard is seen on the other display and visa versa. When you meet a person that does not sign, you habd them one of the devices sit down and type to them. These can be easily made using a couple of small hand held computers and a manufacturer currently makes sets of portable terminals preprogrammed to do this.

Vector scopes can be used and many televisions have been converted into deaf communication vector scopes. These devices allow both one on one communication and telecommunications over radio, intercom, internet and telephone without requiring the other person to have a device. The human speech shows up a a moving glob on the screen. These can be very difficuly to learn to read and the device design can effect the readability. Home made displays using Television or computer monitors vary drasticaly

Devices for use device to device
The Telecommunications Device for the Deaf can be used for one on one device to device communications. In some cases a sprcial null modem cable or local loop device is required to emulate the telephone network and avoid the need to call each other. Several TDD manufacturers have local loop capability and some TDDs and TTYs can be operated stand alone. This works great as clong as you do not mind looking at the same screen and typing to each other.

Vector Scopes
One should be cautioned that going out and buying a vector scope or making one from a television set or computer monitor will not provide communications capability. Human voice fed to the inputs of a vector scope will display a diagonal line that flickers with the voice volume and can not be read or understood. Inductive and capacitive reactive networks are used to induce a phase shift causing the human voice make unique patterns.

Some of these networks are proprietary and some are in the public domain. The Lizzy Lissajous published in popular electronics in the early 1960s is an example of non proprietary network. That schematic never included the inductance of the yoke coil and therefor is not accurately reproducible.

You can experiment and create your own network with capacitors from an electronic parts supplier. If you are using a television or computer monitor you must first cut the wires to the yoke. This may cause the monitor to quit working altogether if the display needs the yoke connected to function. Many do not. If the display continues to work, you will see a dot in the middle of the screen. When your connect the audio signal from an audio amplifier to the yoke wires you have cut, one pair will make a vertical line and the other will make a horizontal line. Connect the amplifier directly to the one that makes the shortest line and use a capacitor to connect to the other pair. Try capacitors between 1 and 200 micro farad and put a variable resistor in parallel to the capacitor to adjust for voice frequency. When you get an open glob on the screen that changes shape with every different voice sound, you have a VED.

All the above: —Preceding unsigned comment added by Scottprovost (talk • contribs)


 * A lot of the above is perfectly good article material and should be copied over. -- RHaworth 13:25, 27 February 2007 (UTC)

Redirect
I have converted the page to a redirect because Telecommunications device for the deaf is a general article about such devices. This article was therefore a fork. The only useful content it had was about Vector Scooes which is a) repeated above, b) how-to material - try capacitors and c) hopelessly "last-century" - surely we have digital devices now which do a much better job? -- RHaworth 13:25, 27 February 2007 (UTC)