FAX is the abbreviation of facsimile process. A FAX machine is highly elector-mechanical machine. A FAX machine can send or receive pictures and text over a telephone line. The principle of FAX machine is by digitizing an image dividing it into a grid of DOTS (One) and NO DOTS (Zero) at high resolution. This is called as bitmap. This works more on the principle of photo imaging. Each dot is either ON or OFF. The transmission of these bits is transmitted like normal computer data over telephone lines. The received data is Re-translated in the form of DOTS and NO DOTS. A FAX machine consists of (a) an optical scanner for digitizing images on paper, (b) a printer for printing incoming FAX messages, and (c) a telephone for transmission and reception. The received data is printed on thermal paper. Some of the features that differentiate one FAX machine from another include the following: Modem Speed: FAX machines transmit data at different rates, from 4,800 bps to 28,800 bps. A 9,600-bps FAX machine typically requires 10 to 20 seconds to transmit one page. Printer Type: A thermal printer recognizes Dots and NO dots. Wherever there is a DOT, by thermal action, it generates a Dot. Paper Cutter: This is usually an optional facility. Paper Feed: The paper from the thermal paper roles are advanced step by step, after getting a synchronizing pulse from the transmitter. The distance to which it moves horizontally and vertically is standardized. Auto dialing and time dialing: These are facilities that vary from manufacturer to manufacturer. The FAX Machine Demonstrator Model FAX-1 is intended to demonstrate the principles of FAX transmission and reception. This demonstrator can be connected to normal telephone lines for actual transmission and reception. The front panel consists of various blocks to broadly indicate the system configuration. Test points (TP) are provided wherever necessary for waveform observations using an oscilloscope. Specifications: - Transmission compatibility: ITU-T/CCITT Group 3
- Scanner: Flatbed scanning with CCD type image sensor
- Document size: Max - 257mm X 1000mm (with operator assistance)
- Min ? 148mm X 105 mm
- Effective scanning width: 208mm
- Recording: Thermal print head
- Print media: High sensitivity thermal recording paper
- Resolution: Horizontal ? 203 pixels / Inch
- Coding scheme: MH, MR (conforms to ITU-T/CCITT)
- Modem type: ITT-T/CCITT V.29
- Modem speed: 300, 2400, 4800, 7200 or 9600 bps
- Power supply: Mains operated 230V AC @ 50Hz.
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