home *** CD-ROM | disk | FTP | other *** search
Text File | 1992-05-25 | 5.5 KB | 135 lines | [TEXT/McSk] |
- Installing a modem in Germany can be a very time-consuming job. The PTT comes
- with two wires (named a and b, b=Ground), but then there are several
- different possibilities. This notice here gives some hints.
-
- First you must know, that the german PTT has a different concept. If you have
- more than one device on one telephone line, and one is active, all other must
- be dead. The PTT tries to garantie privacy. This concept leads to the fact,
- that if you have devices in parallel (this is forbidden), and one device is
- dialing, the other will ring or detect a ring. The privacy concept depends
- therefore on special switching facilities build into the telephones.
-
- Old style connector:
-
- VDO4 Connector:
-
- 4 3 2 1 a and b the telephone wires
- | | | | E means the local Ground (Earth)
- E W b a W is the Bell (German: Wecker)
-
- The normal telephone connects a and W, if the handset on the telephone. (It
- drives a second bell, perhaps). If you pick up the handset the connection of
- a-W is opened.
-
- VDO7 Connector:
-
- 7 6 5 4 3 2 1
- | | | | | | |
- G E W b a b' a'
-
- This connector is used at the main-device, if two devices are connected
- to the line. a' and b' are driven from the connected device and go to
- the second telephone. But the same connector VDO7 is used, when a modem or
- automatic answering system is installed. In this case the ADO8 connector is
- the first connector.
-
-
- ADO8 for Modems:
-
-
- a --- 1 8 --- a'
- E --- 2 7 --- W
- G --- 3 6 --- Z
- b --- 4 5 --- b'
-
-
- If the ADO8 Plug is not inserted, two internal switchec connect a with a' and
- b with b'. So if you want to connect somthing to the telephone line, you can
- simply use the pins 1 and 4 of the ADO8. But if you want to use the telephone
- behind properly, certain connection have to be made, depending on the type of
- equipment, that is installed.
-
-
- Sometimes you find ADO4 Connectors:
-
-
- a --- 1 8
- 2 7 --- W
- 3 6
- b --- 4 5 --- E
-
- The ADO4 has also two internal switches for a and b. But the other sides of
- the switches are connected to internal screws.
-
-
- New connectors TAE6:
-
- The connector type TAE is available from TAE6 to TAE16, depending on the
- pin count. Mostly TAE6 is used. In the future it is planned to use the modular
- jack adapter called "western"-connectors from german PTT. But at this time
- TAE6 is installed for new lines.
-
-
- 1 2 3 4 5 6
- | | | | | |
- | | +- G E -+ | |
- | +----- b b'-----+ |
- +--------- a a'---------+
-
- The logic is just the same as with the above ones. The TAE6 connects a with a'
- and b with b', if the plug is not inserted. But like the ADO8 the TAE6 can be
- coded as N (normal) and F (TeleFon). A modem is connected to the N-coded TAE6.
- But the coding can be overwritten, if you use a bit more energy when inserting
- the plug (The other possibility is to cut the coding with a knife from the
- plug).
-
- Now, if you have a jack adapter, what can be done?
-
- First, there are smome converters available. They are available from ADO8 to
- TAE6 (working with all equipment modems/answering machines). And there are
- converting adapters from TAE6 to Jack (RJ11). Normally they do garantee to
- give you access to a and b, but they do not garantee that the other equipment
- is working well.
-
- (With the Worlport Modem series, we sell Cables one side Jack, other side
- TAE6, coded as F or N, and direct connection between a and a'and b and b'.)
-
- The best is, to bring along a modem plus thelephone. And if you find a and b,
- all will work fine, but make shure, that you use the CCITT-Make/Brake ratio
- for dialing. Otherwise you will often get a connection to a wrong number.
-
- Additonally there is another barrier. Some, especially the older systems, need
- a special switch to let you access the PTT lines, when you are connected to an
- inhouse system. This is done by connecting E with a. If you need such a
- switch, only approved modems will offer it. The corresponding Hayes command is
- ">" or ":", depending if the modem goes offhook before or after the modem goes
- online.
-
- I'm sorry, there is no simple rule how to get online with a modem. It
- mostly make sense to travel with a screw-driver and clips. Or to use cups.
- (We can supply you with the Tandy-Cups for the Worldport Modem series, as we
- are Tandy dealers (send EMAIL). Please note, that the European Tandy-Cups are
- different from those in the US. Most European ones, with a PTT sign are not
- able to operate at 1200 Baud. Therfore we sell the US-Originals, which even
- sometimes work with 2400 Baud).
-
-
- I know that this text is not complete. There are special switching units
- called AWADO1 and AWADO3. They allow to use two devices on the same line. But
- instead of simply using the lines a and b, they need the W signal from the
- telephone device to work properly. And the german PTT uses several different
- diagramms. Often int is not easy to find out, what sort of diagramm was used
- and why. But I hope that you are now able to find a and b on all sorts
- of connectors! If you need a special advice, send EMAIL.
-
-
- RzK D.Kpke, Bitzenstrasse 11, D-5464 Asbach Ww., FAX 49 2683 4537
-
- /exit
- /EXIT
-
-
-
- /EXIT
-
-