An instrument combined with a telephone. In this case, an arriving fax is either automatically registered, or the operator must manually switch over to fax mode in order to receive faxes. Incoming faxes are electronically distributed via the network to their final destinations. Any PC can send faxes, using modern fax software, and faxes can then be generated using special fax software and other software packages, such as word processors.
Facsimile apparatus makes use of an optical scanner and a converter.
An optical scanner converts the text or graphics on a page to digital bit map format, ready for transmitting to another fax machine. Depending upon the type of printer, this can be on heat-sensitive paper, plain paper, or a computer screen. Depending on the sophistication of the fax apparatus, the image of the fax can also be saved on a computer hard drive. Most independent fax machines allow for voice communication. The transmission speed of such stand-alone machines varies from 3 to 50 seconds per page.