Junk fax unlawful to send an individual an unsolicited sales and marketing fax without any prior consent of the customer. If the fax receiver is a company or corporate instances, fax communications are permitted unless the subscriber has previously notified the caller that such communications should not be sent on that line; or the subscriber’s line is listed in the register kept under regulation 25 of PECR. This register is maintained on behalf of OFCOM by the Direct Marketing Association and is branded as the Facsimile Preference Service (“FPS”). Unsolicited faxes are regulated by the Canadian Radio-television and Telecommunications Commission (CRTC) and
Fax systems used direct conversions of image darkness to audio tone in a continuous or analog manner. Since the 1980s, most machines modulate the transmitted audio frequencies using a digital representation of the page which is compressed to quickly transmit areas which are all-white or all-black. Scottish inventor Alexander Bain worked on chemical mechanical fax type devices and in 1846 was able to reproduce graphic signs in laboratory experiments. He received British patent 9745 on May 27, 1843 for his "Electric Printing Telegraph". Frederick Bakewell made several improvements on Bain's design and demonstrated a telefax machine. The Pantelegraph was invented by