The HP 7470 was a small low-cost desktop pen plotter introduced by Hewlett-Packard's San Diego division in 1982.[1] It was the first small-format plot that moved the paper, rather than the pens.[2] It used a revolutionary "grit wheel" design which moved the paper held in place by a wheel with embedded grit and a pinch roller.
The HP 7470 had two pens, one on either side and plotted on ANSI A (8.5 x 11 inch) or A4-sized paper.[3] It was much less expensive than the previous flatbed design. It was very heavy but had 4 pens. The HP 7475 used a rotating carousel with six pens. That plotter was used in greeting card kiosks. This design was also scaled up for very large pen plotters. These were driven by the HP-GL plotter language which used ASCII commands such as PA 300, 4500;PD;. The plotter had three electrical interfaces: HP-IB, RS-232, and HP-IL for HP handheld calculators.
Pen plotters became obsolete with the adoption of ink-jet printers, and processors fast enough to rasterize complex images. Houston Instrument and other manufacturers would follow with similar plotters.
References[edit]
- ^ "HP 7470". HP Computer Museum. Retrieved Feb 16, 2018.
- ^ "HP 7470A Plotter - Computing History". www.computinghistory.org.uk. Centre for Computing History. Retrieved 24 February 2018.
- ^ Rosch, Winn L. (1983). Two Computerized Draftsmen. PC Mag, Ziff Davis, Inc. pp. 288–308. Retrieved 24 February 2018.
Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction