9 SPECIALIZED COMMUNICATIONS
SLOW SCAN TV/ FACSIMILE
Nowadays instead of a scan converter, many hams use a personal computer, a software application, and an interface attached to the transceiver. This is much cheaper, more flexible, and does not require a TV set. In recent years, many low cost digital cameras have become available. You can transfer images from these cameras into your computer.
For further information, consult reference books about Amateur Radio. The frequencies (measured in kHz) commonly used for SSTV operation are listed below:
U.S.A./ Canada | ARU Region 1 | ||
(Europe/ Africa) | |||
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3845, 3857 | 3730 | ~ 3740 | |
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7171 | 7035 | ~ 7045 | |
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14230, 14233 | 14225 | ~ 14235 | |
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21340 | 21335 | ~ 21345 | |
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28680 | 28675 | ~ 28685 | |
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145500 |
| — | |
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Fax (facsimile) is one of the original image transmission modes. Using this mode allows you to exchange more detailed graphics than SSTV. Amateur Radio fax functions much like old analog fax systems. It scans paper and converts acquired image data into a series of tones representing white and black portions of the image. Because fax requires longer transmission time, you should use it only when band conditions are stable with strong signals.
Popular fax frequencies include the following:
•7245, 14245, 21345 (International Net), and 28945 kHz
Operating on SSTV or fax mainly involves learning the functionality of your computer application or accessory hardware that supports these modes. Consult the instruction manual that comes with your software or accessory equipment.
Note: When operating either SSTV or fax, use a fast AGC setting and switch OFF your Speech Processor, for best results.
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