Encoding

The data of your fax transmission are encoded and com- pressed for the transmission. The minimum standard is MH (Modified Huffmann). Better encoding methods are MR (Modified Read) or MMR (Modified Modified Read).

Error Correction Mode (ECM)

The ECM method reduces transmission errors that result, for example, from bad telephone lines, thereby reducing the duration of transmissions. Both of the connected fax machines must support ECM.

Fax Groups

Fax machines are classified in terms of internationally standardised fax groups based on their transfer type and speed. Connections between two devices of different groups is possible; the lowest common transfer rate is selected. The determination of the speed takes place during the handshake (see Handshake). Fax groups 1 to 3 are ana- logue fax machines. Nowadays, groups 1 and 2 are hardly to be found any longer; fax machines of group 3—which have a transfer speed that ranges from 9,600 to 33,600¦bps—are currently most standard. Group 4 fax machines are digital devices that function exclusively on ISDN systems. They have a maximum transfer speed of 64,000¦bps.

Fax Polling

With active fax polling, one can retrieve a document from another fax machine. For fax polling from a larger com- pany offering several polling services, you can also enter sub-addresses / direct-dial numbers. In order to do this, you must insert a dialling pause between the fax number and the sub-address (see Dialling Pause).

Fax Signal, CNG Tone (= Calling Signal)

The tone that a fax machine sends out to announce a fax transmission. When the CNG tone occurs, the fax switch of the device recognises an incoming fax call and starts the fax reception.

Fax Switch

The fax switch checks incoming telephone calls and con- trols the ringing behaviour of the fax machine. According to the selected mode, fax transmissions will be received either automatically or manually.

Flash Key (R-key)

With the flash key, you can make use of additional tele- phone services if these special functions are enabled for your telephone line. The R key has replaced the hook-flash function. (see Call Waiting, Call-toggling).

Handshake

The handshake is the initial and final phase of a fax trans- mission. After establishing of the connection, fax machines check the group affiliation and features such as size com- pression or grey tones. After the fax transmission has been completed and before the connection is terminated, the receiving device confirms receipt of the transmission (see Fax Groups).

Hook-Flash Function

See Flash Key

ISDN

Integrated Services Digital Network

ITU

International Telecommunications Union (UN organisa- tion)

LCD

Liquid Crystal Display

LED

LED: Light Emitting Diode

Memory

If there is no paper or toner in your device, the device will store incoming fax transmissions in its memory.

MH

Modified Huffmann (encoding process for faxes, see Encoding)

MMR

Modified Modified Read (encoding process for faxes, see Encoding)

MR

Modified Read (encoding process for faxes, see Encoding)

Outside Line Access Code

The outside line access code is the number or letter that must be dialled before the actual telephone number on a telephone of a private branch exchange in order to estab- lish a connection to the public telephone network (see Pri- vate Branch Exchange).

PABX/PBX

Private Automatic Branch Exchange

Polling

see Fax Polling

POTS

Plain Old Telephone Service

Private Branch Exchange

Private branch exchanges are common in larger compa- nies. Even private ISDN systems can be branch exchanges. To establish a connection to the public telephone network from a private branch exchange, one must dial a number or press a key before the actual telephone number; in most cases this is zero (see Outside Line Access Code).

PSTN

Public Switched Telephone Network

Pulse Dialling

A dialling process that is used in older telephone networks. You hear a clicking for each number dialled (see Tone Dialling).

RJ-11

Registered Jack 11 (also called Western plug, standardised telephone plug)

Scanning

The reading of a document into the fax memory or into the computer in order to send it, copy it or edit it.

EN

Glossary · Encoding

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Philips 253117544-B Encoding, Error Correction Mode ECM, Fax Groups, Fax Polling, Fax Signal, CNG Tone = Calling Signal