1891:
1994:
the presence of interference. In order to compare the two lines, a piezoelectric delay unit to delay the signal by a time that is equal to the duration of each line, 64 ÎĽs, is inserted in one of the two signal paths that are compared. In order to produce the required delay in a crystal of convenient size, the delay unit is shaped to reflect the signal multiple times through the crystal, thereby greatly reducing the required size of the crystal and thus producing a small, rectangular-shaped device.
1696:(a combination of speaker and microphone) at either end. Signals from the radar amplifier were sent to the transducer at one end of the tube, which would generate a small wave in the mercury. The wave would quickly travel to the far end of the tube, where it would be read back out by the other transducer, inverted, and sent to the display. Careful mechanical arrangement was needed to ensure that the delay time matched the inter-pulse timing of the radar being used.
1647:". This resulted in the delayed signal from an earlier pulse exiting the delay unit the same time that the signal from a newer pulse was received from the antenna. One of the signals was electrically inverted, typically the one from the delay, and the two signals were then combined and sent to the display. Any signal that was at the same location was nullified by the inverted signal from a previous pulse, leaving only the moving objects on the display.
1635:. The antenna is connected to the transmitter, which sends out a brief pulse of radio energy before being disconnected again. The antenna is then connected to the receiver, which amplifies any reflected signals and sends them to the display. Objects farther from the radar return echos later than those closer to the radar, which the display indicates visually as a "blip", which can be measured against a scale in order to determine range.
1840:
1962:
1768:
mercury was limited. Other technical drawbacks of mercury included its weight, its cost, and its toxicity. Moreover, to get the acoustic impedances to match as closely as possible, the mercury had to be kept at a constant temperature. The system heated the mercury to a uniform above-room temperature setting of 40 °C (104 °F), which made servicing the tubes hot and uncomfortable work. (
2003:
1742:
1714:
1780:
the beam then required considerable tuning to make sure that both transducers were pointed directly at each other. Since the speed of sound changes with temperature, the tubes were heated in large ovens to keep them at a precise temperature. Other systems instead adjusted the computer clock rate according to the ambient temperature to achieve the same effect.
1926:. Delay-line memory was also used for video memory in early terminals, where one delay line would typically store 4 lines of characters (4 lines Ă— 40 characters per line Ă— 6 bits per character = 960 bits in one delay line). They were also used very successfully in several models of early desktop
1639:"clutter". This was not an ideal situation; it required careful aiming, which was difficult for smaller mobile radars, and did not remove other sources of clutter-like reflections from features like prominent hills, and in the worst case would allow low-flying enemy aircraft to literally fly "under the radar".
1874:
waves are considerably more resistant to problems caused by mechanical imperfections, so much that the wires could be wound into a loose coil and pinned to a board. Due to their ability to be coiled, the wire-based systems could be as long as needed, so tended to hold considerably more data per unit;
1638:
Non-moving objects at a fixed distance from the antenna always return a signal after the same delay. This would appear as a fixed spot on the display, making detection of other targets in the area more difficult. Early radars simply aimed their beams away from the ground to avoid the majority of this
1779:
A considerable amount of engineering was needed to maintain a clean signal inside the tube. Large transducers were used to generate a very tight beam of sound that would not touch the walls of the tube, and care had to be taken to eliminate reflections from the far end of the tubes. The tightness of
1725:
After the war, Eckert turned his attention to computer development, which was a topic of some interest at the time. One problem with practical development was the lack of a suitable memory device, and Eckert's work on the radar delays gave him a major advantage over other researchers in this regard.
1561:
are connected between the output of the delay line and the input. These devices recirculate the signals from the output back into the input, creating a loop that maintains the signal as long as power is applied. The shaper ensures the pulses remain well-formed, removing any degradation due to losses
1993:
standard for color broadcasts compares the signal from two successive lines of the image in order to avoid color shifting due to small phase shifts. By comparing two lines, one of which is inverted, the shifting is averaged, and the resulting signal more closely matches the original signal, even in
2074:
In modern computers operating at gigahertz speeds, millimeter differences in the length of conductors in a parallel data bus can cause data-bit skew, which can lead to data corruption or reduced processing performance. This is remedied by making all conductor paths of similar length, delaying the
1733:
needed to complete an operation, which typically start and end with reading or writing memory. Thus the delay lines had to be timed such that the pulses would arrive at the receiver just as the computer was ready to read it. Many pulses would be in-flight through the delay, and the computer would
1642:
To filter out static objects, two pulses were compared, and returns with the same delay times were removed. To do this, the signal sent from the receiver to the display was split in two, with one path leading directly to the display and the second leading to a delay unit. The delay was carefully
2010:
Electric delay lines are used for shorter delay times (nanoseconds to several microseconds). They consist of a long electric line or are made of discrete inductors and capacitors arranged in a chain. To shorten the total length of the line, it can be wound around a metal tube, getting some more
1767:
in mercury (1450 m/s) meant that the time needed to wait for a pulse to arrive at the receiving end was less than it would have been with a slower medium, such as air (343.2 m/s), but it also meant that the total number of pulses that could be stored in any reasonably sized column of
1985:
material, typically quartz. Current fed into one end of the crystal would generate a compressive wave that would flow to the other end, where it could be read. In effect, piezoelectric material simply replaced the mercury and transducers of a conventional mercury delay line with a single unit
1800:
of memory, stored in 16 delay lines holding 560 bits each (words in the delay line were composed from 36 pulses, one pulse was used as a space between consecutive numbers). The memory was later expanded to 512 words by adding a second set of 16 delay lines. In the
1699:
All of these systems were suitable for conversion into a computer memory. The key was to restore and recycle the signals, so they would not disappear after traveling through the delay. This was relatively easy to arrange with simple electronics.
2071:), which transport a stored electric charge stepwise from one end to the other. Both digital and analog methods are bandwidth limited at the upper end to the half of the clock frequency, which determines the steps of transportation.
1805:
the capacity of an individual delay line was smaller, each column stored 120 bits, requiring seven large memory units with 18 columns each to make up a 1000-word store. Combined with their support circuitry and
1986:
combining both. However, these solutions were fairly rare; growing crystals of the required quality in large sizes was not easy, which limited them to small sizes and thus small amounts of data storage.
1887:). Of course, this also meant that the time needed to find a particular bit was somewhat longer as it travelled through the wire, and access times on the order of 500 microseconds were typical.
1600:
applied for a patent for a delay-line memory system on
October 31, 1947; the patent was issued in 1953. This patent focused on mercury delay lines, but it also discussed delay lines made of
1658:
experimented with a number of systems, including glass, quartz, steel and lead. The
Japanese deployed a system consisting of a quartz element with a powdered glass coating that reduced
2278:
Kissner, Michael; Leonardo Del Bino; Päsler, Felix; Caruana, Peter; Ghalanos, George (2024). "An All-Optical
General-Purpose CPU and Optical Computer Architecture".
1827:
Some mercury delay-line memory devices produced audible sounds, which were described as akin to a human voice mumbling. This property gave rise to the slang term
2216:
1863:. When bits from the computer entered the magnets, the nickel would contract or expand (based on the polarity) and twist the end of the wire. The resulting
1565:
The memory capacity equals the time to transmit one bit divided by the recirculation time. Early delay-line memory systems had capacities of a few thousand
2385:
1828:
612:
607:
2335:
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2083:
In the field of optical computing, an optical delay line can be used in a similar fashion to how acoustic or electrical delay lines were used.
1682:
1501:
1042:
2063:
storage device. This can be done digitally or with a discrete-time analogue method. The analogue one uses charge transfer devices (either
1650:
Several different types of delay systems were invented for this purpose, with one common principle being that the information was stored
1553:
technology had been used since the 1920s to delay the propagation of analog signals. When a delay line is used as a memory device, an
203:
990:
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1915:
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1763:; this minimized the energy loss and the echoes when the signal was transmitted from crystal to medium and back again. The high
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1577:, it is necessary to wait for the signal representing its value to circulate through the delay line into the electronics. The
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to transfer data to a read head at one point on the circumference from a write head elsewhere around the circumference.
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to read or write any particular address is thus time and address dependent, but no longer than the recirculation time.
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For a computer application the timing was still critical, but for a different reason. Conventional computers have a
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capacitance against ground and also more inductance due to the wire windings, which are lying close together.
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1989:
A better and more widespread use of piezoelectric delay lines was in
European television sets. The European
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J. P. Eckert, Jr., A Survey of
Digital Computer Memory Systems, Proceedings of the IRE, October 1953.
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used steel rods wrapped into a helix, but this was useful only for low frequencies under 1 MHz.
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1569:(although the term "bit" was not in popular use at the time), with recirculation times measured in
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Electric delay line (450 ns), consisting of enamelled copper wire, wound around a metal tube
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arrival time for what would otherwise be shorter travel distances by using zig-zagging traces.
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A similar solution to the magnetostrictive system was to use delay lines made entirely of a
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color TV; it delays the color signal by 64 ÎĽs. Manufacturer: VEB ELFEMA Mittweida (
1839:
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as an ultrasonic delay medium, claiming that it had the necessary acoustic properties.)
1907:
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wave would then move down the wire just as the sound wave did down the mercury column.
1818:, which was considerably faster than the mechanical systems used on earlier computers.
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2320:- Shows details of the torsion delay lines inside this electronic calculator of 1967
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A radar system consists principally of an antenna, a transmitter, a receiver, and a
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1535:. Like many modern forms of electronic computer memory, delay-line memory was a
17:
2305:– has an image of a Ferranti wire-based system about halfway down the page
2002:
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The first practical de-cluttering system based on the concept was developed by
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Delay-line memory was far less expensive and far more reliable per bit than
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How nickel delay line memory works, some information about the construction
1910:. It was used into the late 1960s, notably on commercial machines like the
2242:"RETICON: Product Summary: Discrete Time Analog Signal Processing Devices"
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2211:(Ph.D.). Eindhoven, Netherlands: Technische Universiteit. pp. 7–8.
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Another way to create a delay time is to implement a delay line in an
1620:
The basic concept of the delay line originated with World War II
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1859:, were attached to either side of the end of the wire, inside an
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from reflections from the ground and other non-moving objects.
2041:
to match the velocity of the electrons to the velocity of the
1990:
1970:
1851:
as the storage medium. Transducers were built by applying the
1794:
1773:
1670:
used a magnesium alloy originally developed for making bells.
1655:
1566:
1246:
1133:
903:
2311:– contains a diagram of the magnetostrictive transducer
2205:
Ultrasonic delay lines for the PAL colour-television system
1824:, completed in November 1949, also used delay-line memory.
1643:
tuned to be some multiple of the time between pulses, or "
1584:
Use of a delay line for a computer memory was invented by
1855:; small pieces of a magnetostrictive material, typically
1524:, mostly obsolete, that was used on some of the earliest
1870:
Unlike the compressive wave used in earlier devices,
2217:"A delay line for PAL colour television receivers"
1588:in the mid-1940s for use in computers such as the
2022:for phase matching in high-frequency circuits or
1738:to find the particular bit it was looking for.
1810:, the memory subsystem formed its own walk-in
2342:Display Terminal built with 32 TV delay lines
1814:. The average access time was about 222
1495:
8:
2338:, filed October 1947, patented February 1953
1662:that interfered with proper reception. The
1879:units were typical on a board only 1
1734:count the pulses by comparing to a master
1502:
1488:
26:
2283:
2191:. Corning Electronics. 1963. RRP 8/63 5M.
2166:"An Ultrasonic Memory Unit for the EDSAC"
2140:
1745:Diagram of mercury delay line as used in
1608:delay lines, and delay lines built using
2326:, still used in a German computer museum
2164:Wilkes, M. V.; Renwick, W. (July 1948).
1532:
2092:
1847:A later version of the delay line used
1664:United States Naval Research Laboratory
768:
563:
29:
1759:is close to that of the piezoelectric
1683:Moore School of Electrical Engineering
1043:Vision Electronic Recording Apparatus
7:
1531:, and is reappearing in the form of
2361:Nickel delay line for EDSAC replica
2336:Eckert–Mauchly Computer Corporation
2123:Wilkes, Maurice V. (January 1968).
1945:introduced in 1965, and the Litton
1602:strings of inductors and capacitors
204:Data validation and reconciliation
25:
2386:History of electronic engineering
254:Distributed file system for cloud
2353:The National Museum of Computing
1916:Highgate Wood Telephone Exchange
1894:100-microsecond delay-line store
1685:. His solution used a column of
1624:research, as a system to reduce
1573:. To read or write a particular
102:Areal density (computer storage)
2260:from the original on 2022-12-05
921:Programmable metallization cell
1934:EC-130 (1964) and EC-132, the
1793:, began operation with 256 35-
484:Persistence (computer science)
1:
1514:Early type of computer memory
1352:Electronic quantum holography
1906:, and yet far faster than a
1835:Magnetostrictive delay lines
703:Video RAM (dual-ported DRAM)
499:Non-RAID drive architectures
1539:, but as opposed to modern
2407:
2303:Acoustic Delay Line Memory
2029:hollow resonator lines in
1679:University of Pennsylvania
1645:pulse repetition frequency
1292:Holographic Versatile Disc
1191:Compact Disc Digital Audio
1063:Magnetic-tape data storage
682:Content-addressable memory
1957:Piezoelectric delay lines
489:Persistent data structure
384:Digital rights management
2224:Philips Technical Review
2215:Backers, F. Th. (1968).
2125:"Computers Then and Now"
1951:programmable calculators
1924:IBM 2848 Display Control
1786:, the second full-scale
1543:, delay-line memory was
1364:DNA digital data storage
1347:Holographic data storage
836:Solid-state hybrid drive
122:Network-attached storage
2349:"What store for EDSAC?"
2324:Magnetostrictive memory
1943:programmable calculator
1853:magnetostrictive effect
1843:Torsion wire delay line
1359:5D optical data storage
1176:3D optical data storage
899:Universal Flash Storage
304:Replication (computing)
249:Distributed file system
139:Single-instance storage
117:Direct-attached storage
97:Continuous availability
2202:Backers, F.T. (1968).
2173:Electronic Engineering
2069:charge-coupled devices
2065:bucket-brigade devices
2007:
1978:
1895:
1844:
1749:
1722:
1675:J. Presper Eckert
1586:J. Presper Eckert
1232:Nintendo optical discs
449:Storage virtualization
319:Information repository
259:Distributed data store
2331:U.S. patent 2,629,827
2142:10.1145/321439.321440
2101:U.S. patent 2,629,827
2043:electromagnetic waves
2039:travelling-wave tubes
2005:
1964:
1928:electronic calculator
1893:
1842:
1755:was used because its
1744:
1716:
735:Mellon optical memory
723:Williams–Kilburn tube
439:Locality of reference
244:Clustered file system
70:Memory access pattern
2355:. 13 September 2013.
2344:Complete description
2053:free-electron lasers
2014:Other examples are:
1998:Electric delay lines
1772:proposed the use of
1704:Acoustic delay lines
1541:random-access memory
1431:Magnetic-core memory
1078:Digital Data Storage
1038:Quadruplex videotape
479:In-memory processing
369:Information transfer
264:Distributed database
127:Storage area network
107:Block (data storage)
2376:Digital electronics
2309:Delay line memories
2175:. pp. 209–210.
2079:Optical delay lines
1831:for these devices.
1709:Mercury delay lines
1533:optical delay lines
1028:Phonograph cylinder
966:Electrochemical RAM
818:Solid-state storage
434:Memory segmentation
132:Block-level storage
2129:Journal of the ACM
2061:integrated circuit
2008:
1979:
1939:Programma 101
1922:machines, and the
1896:
1845:
1757:acoustic impedance
1750:
1723:
1717:Mercury memory of
1537:refreshable memory
1437:Plated-wire memory
1402:Paper data storage
1048:Magnetic recording
474:In-memory database
459:Memory-mapped file
404:Volume boot record
399:Master boot record
389:Volume (computing)
364:Data communication
289:Data deduplication
2391:Mercury (element)
2334:"Memory System",
2018:short coaxial or
1967:analog delay line
1551:Analog delay line
1545:sequential-access
1518:Delay-line memory
1512:
1511:
1109:8 mm video format
1033:Phonograph record
852:Flash Core Module
830:Solid-state drive
729:Delay-line memory
688:Computational RAM
591:Scratchpad memory
429:Disk partitioning
154:Unstructured data
80:Secondary storage
18:Delay line memory
16:(Redirected from
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2114:
2111:
2105:
2103:
2097:
2020:microstrip lines
1930:, including the
1886:
1791:digital computer
1616:Genesis in radar
1606:magnetostrictive
1504:
1497:
1490:
1449:Thin-film memory
1443:Core rope memory
1369:Universal memory
1332:Millipede memory
1322:Racetrack memory
1287:Ultra HD Blu-ray
1099:Linear Tape-Open
1053:Magnetic storage
1021:Analog recording
464:Software entropy
424:Disk aggregation
184:Data degradation
169:Data compression
65:Memory hierarchy
55:Memory coherence
27:
21:
2406:
2405:
2401:
2400:
2399:
2397:
2396:
2395:
2381:Computer memory
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2089:
2081:
2000:
1959:
1884:
1837:
1761:quartz crystals
1711:
1706:
1618:
1562:in the medium.
1522:computer memory
1515:
1508:
1479:
1478:
1397:
1389:
1388:
1342:Patterned media
1312:
1304:
1303:
1171:
1161:
1160:
1156:Hard disk drive
1023:
1013:
1012:
993:
982:
981:
936:
926:
925:
847:IBM FlashSystem
842:USB flash drive
781:
764:
763:
718:
710:
709:
698:Dual-ported RAM
576:
559:
558:
519:Cloud computing
379:Copy protection
299:Data redundancy
229:Shared resource
199:Data validation
174:Data corruption
149:Structured data
60:Cache coherence
45:
31:Computer memory
23:
22:
15:
12:
11:
5:
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2402:
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2315:Litton Monroe
2312:
2306:
2298:
2297:External links
2295:
2292:
2291:
2270:
2233:
2194:
2188:Glass Memories
2178:
2156:
2115:
2106:
2091:
2090:
2088:
2085:
2080:
2077:
2057:
2056:
2046:
2037:as helices in
2027:
1999:
1996:
1965:An ultrasonic
1958:
1955:
1949:2000 and 3000
1908:latching relay
1885:~30 cm Ă— 30 cm
1836:
1833:
1788:stored-program
1765:speed of sound
1710:
1707:
1705:
1702:
1617:
1614:
1610:rotating disks
1575:memory address
1513:
1510:
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1484:
1481:
1480:
1477:
1476:
1470:
1464:
1461:Twistor memory
1458:
1452:
1446:
1440:
1434:
1428:
1422:
1417:
1411:
1405:
1398:
1395:
1394:
1391:
1390:
1387:
1386:
1381:
1379:Quantum memory
1376:
1371:
1366:
1361:
1356:
1355:
1354:
1344:
1339:
1334:
1329:
1324:
1319:
1313:
1311:In development
1310:
1309:
1306:
1305:
1302:
1301:
1296:
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1289:
1284:
1279:
1274:
1269:
1264:
1259:
1254:
1249:
1244:
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1234:
1229:
1224:
1222:Super Video CD
1219:
1214:
1209:
1204:
1199:
1194:
1188:
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1172:
1167:
1166:
1163:
1162:
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1126:
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1116:
1111:
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1101:
1096:
1091:
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1075:
1070:
1065:
1060:
1055:
1045:
1040:
1035:
1030:
1024:
1019:
1018:
1015:
1014:
1011:
1010:
1005:
1000:
994:
988:
987:
984:
983:
980:
979:
974:
969:
963:
958:
948:
943:
937:
932:
931:
928:
927:
924:
923:
918:
917:
916:
911:
906:
901:
896:
891:
886:
881:
879:MultiMediaCard
876:
871:
866:
856:
855:
854:
849:
844:
839:
833:
827:
815:
810:
809:
808:
803:
793:
788:
782:
777:
776:
773:
772:
766:
765:
762:
761:
755:
749:
744:
741:Selectron tube
738:
732:
726:
719:
716:
715:
712:
711:
708:
707:
706:
705:
695:
690:
685:
679:
674:
669:
668:
667:
657:
656:
655:
650:
645:
640:
635:
630:
625:
620:
615:
610:
605:
595:
594:
593:
588:
581:Hardware cache
577:
572:
571:
568:
567:
561:
560:
557:
556:
551:
546:
541:
536:
534:Edge computing
531:
526:
521:
516:
514:Grid computing
511:
509:Bank switching
506:
501:
496:
491:
486:
481:
476:
471:
466:
461:
456:
454:Virtual memory
451:
446:
441:
436:
431:
426:
421:
419:Disk mirroring
416:
411:
406:
401:
396:
391:
386:
381:
376:
374:Temporary file
371:
366:
361:
356:
351:
346:
341:
336:
331:
326:
324:Knowledge base
321:
316:
314:Storage record
311:
309:Memory refresh
306:
301:
296:
294:Data structure
291:
286:
281:
276:
271:
266:
261:
256:
251:
246:
241:
236:
231:
226:
221:
216:
211:
206:
201:
196:
191:
189:Data integrity
186:
181:
179:Data cleansing
176:
171:
166:
161:
156:
151:
146:
141:
136:
135:
134:
129:
119:
114:
112:Object storage
109:
104:
99:
94:
93:
92:
82:
77:
72:
67:
62:
57:
52:
46:
43:
42:
39:
38:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2403:
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2377:
2374:
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2371:
2362:
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2337:
2332:
2328:
2325:
2322:
2319:
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2310:
2307:
2304:
2301:
2300:
2296:
2286:
2281:
2274:
2271:
2256:
2252:
2251:
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2237:
2234:
2229:
2225:
2218:
2207:
2206:
2198:
2195:
2190:
2189:
2182:
2179:
2174:
2167:
2160:
2157:
2152:
2148:
2143:
2138:
2134:
2130:
2126:
2119:
2116:
2110:
2107:
2102:
2096:
2093:
2086:
2084:
2078:
2076:
2072:
2070:
2066:
2062:
2054:
2050:
2047:
2044:
2040:
2036:
2032:
2028:
2025:
2021:
2017:
2016:
2015:
2012:
2004:
1997:
1995:
1992:
1987:
1984:
1983:piezoelectric
1976:
1972:
1968:
1963:
1956:
1954:
1952:
1948:
1944:
1940:
1937:
1933:
1929:
1925:
1921:
1917:
1913:
1909:
1905:
1901:
1892:
1888:
1882:
1878:
1873:
1868:
1866:
1862:
1861:electromagnet
1858:
1854:
1850:
1841:
1834:
1832:
1830:
1825:
1823:
1819:
1817:
1813:
1809:
1804:
1803:UNIVAC I
1799:
1796:
1792:
1789:
1785:
1781:
1777:
1775:
1771:
1766:
1762:
1758:
1754:
1748:
1747:SEAC computer
1743:
1739:
1737:
1732:
1727:
1720:
1715:
1708:
1703:
1701:
1697:
1695:
1692:
1691:piezo crystal
1688:
1684:
1680:
1676:
1671:
1669:
1665:
1661:
1660:surface waves
1657:
1654:in a medium.
1653:
1648:
1646:
1640:
1636:
1634:
1629:
1627:
1623:
1615:
1613:
1611:
1607:
1603:
1599:
1596:. Eckert and
1595:
1594:UNIVAC I
1591:
1587:
1582:
1580:
1576:
1572:
1568:
1563:
1560:
1556:
1552:
1548:
1546:
1542:
1538:
1534:
1530:
1527:
1523:
1520:is a form of
1519:
1505:
1500:
1498:
1493:
1491:
1486:
1485:
1483:
1482:
1474:
1471:
1468:
1467:Bubble memory
1465:
1462:
1459:
1456:
1453:
1450:
1447:
1444:
1441:
1438:
1435:
1432:
1429:
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1220:
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1215:
1213:
1210:
1208:
1205:
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1200:
1198:
1195:
1192:
1189:
1187:
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1182:
1179:
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1177:
1174:
1173:
1170:
1165:
1164:
1157:
1154:
1150:
1147:
1145:
1142:
1140:
1137:
1135:
1132:
1130:
1127:
1125:
1122:
1120:
1117:
1115:
1112:
1110:
1107:
1105:
1102:
1100:
1097:
1095:
1094:Cassette tape
1092:
1090:
1089:Videocassette
1087:
1085:
1082:
1079:
1076:
1074:
1071:
1069:
1066:
1064:
1061:
1059:
1058:Magnetic tape
1056:
1054:
1051:
1050:
1049:
1046:
1044:
1041:
1039:
1036:
1034:
1031:
1029:
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1022:
1017:
1016:
1009:
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1004:
1001:
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992:
986:
985:
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964:
962:
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935:
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929:
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897:
895:
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890:
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880:
877:
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867:
865:
862:
861:
860:
857:
853:
850:
848:
845:
843:
840:
837:
834:
831:
828:
825:
822:
821:
819:
816:
814:
813:ROM cartridge
811:
807:
804:
802:
799:
798:
797:
794:
792:
789:
787:
784:
783:
780:
775:
774:
771:
767:
759:
756:
753:
750:
748:
745:
742:
739:
736:
733:
730:
727:
724:
721:
720:
714:
713:
704:
701:
700:
699:
696:
694:
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680:
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673:
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663:
662:
661:
658:
654:
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639:
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634:
631:
629:
626:
624:
621:
619:
616:
614:
611:
609:
606:
604:
601:
600:
599:
596:
592:
589:
587:
584:
583:
582:
579:
578:
575:
570:
569:
566:
562:
555:
552:
550:
547:
545:
542:
540:
539:Dew computing
537:
535:
532:
530:
529:Fog computing
527:
525:
524:Cloud storage
522:
520:
517:
515:
512:
510:
507:
505:
504:Memory paging
502:
500:
497:
495:
492:
490:
487:
485:
482:
480:
477:
475:
472:
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467:
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427:
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412:
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407:
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392:
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387:
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382:
380:
377:
375:
372:
370:
367:
365:
362:
360:
357:
355:
352:
350:
347:
345:
342:
340:
339:File deletion
337:
335:
332:
330:
329:Computer file
327:
325:
322:
320:
317:
315:
312:
310:
307:
305:
302:
300:
297:
295:
292:
290:
287:
285:
282:
280:
277:
275:
272:
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265:
262:
260:
257:
255:
252:
250:
247:
245:
242:
240:
237:
235:
232:
230:
227:
225:
222:
220:
217:
215:
212:
210:
209:Data recovery
207:
205:
202:
200:
197:
195:
194:Data security
192:
190:
187:
185:
182:
180:
177:
175:
172:
170:
167:
165:
162:
160:
157:
155:
152:
150:
147:
145:
142:
140:
137:
133:
130:
128:
125:
124:
123:
120:
118:
115:
113:
110:
108:
105:
103:
100:
98:
95:
91:
90:floating-gate
88:
87:
86:
83:
81:
78:
76:
73:
71:
68:
66:
63:
61:
58:
56:
53:
51:
48:
47:
41:
40:
36:
32:
28:
19:
2352:
2316:
2273:
2262:. Retrieved
2248:
2236:
2227:
2223:
2204:
2197:
2187:
2181:
2172:
2159:
2132:
2128:
2118:
2109:
2095:
2082:
2073:
2058:
2013:
2009:
1988:
1980:
1897:
1869:
1846:
1829:"mumble-tub"
1826:
1820:
1816:microseconds
1782:
1778:
1751:
1731:clock period
1728:
1724:
1698:
1672:
1652:acoustically
1649:
1641:
1637:
1630:
1619:
1598:John Mauchly
1583:
1571:microseconds
1564:
1559:pulse shaper
1549:
1517:
1516:
1414:Punched tape
1408:Punched card
1374:Time crystal
1242:Hyper CD-ROM
1181:Optical disc
1073:Tape library
1008:FeFET memory
989:Early-stage
869:CompactFlash
864:Memory Stick
824:Flash memory
786:Diode matrix
770:Non-volatile
728:
554:Kryder's law
544:Amdahl's law
469:Software rot
444:Logical disk
344:File copying
279:Data storage
234:File sharing
219:Data cluster
35:data storage
1947:Monroe Epic
1881:square foot
1877:1 kbit
1849:steel wires
1770:Alan Turing
1694:transducers
1473:Floppy disk
1425:Drum memory
859:Memory card
826:is used in:
760:(2002–2010)
725:(1946–1947)
549:Moore's law
394:Boot sector
334:Object file
239:File system
50:Memory cell
2370:Categories
2285:2403.00045
2264:2023-09-07
2230:: 243–251.
2135:(1): 1–7.
2087:References
2049:undulators
2031:magnetrons
1918:, various
1912:LEO I
1902:made from
1900:flip-flops
1808:amplifiers
1396:Historical
1068:Tape drive
894:SmartMedia
717:Historical
414:Disk image
409:Disk array
284:Data store
85:MOS memory
75:Memory map
2317:Epic 3000
2035:klystrons
1977:) in 1980
1953:of 1967.
1872:torsional
1865:torsional
1555:amplifier
1529:computers
1455:Disk pack
1420:Plugboard
1257:DVD-Video
1186:LaserDisc
1084:Videotape
955:3D XPoint
946:Memristor
586:CPU cache
354:Core dump
274:Data bank
224:Directory
2255:Archived
2024:antennas
1941:desktop
1936:Olivetti
1920:Ferranti
1719:UNIVAC I
1668:Raytheon
1592:and the
1384:UltraRAM
1262:DVD card
1217:Video CD
1202:CD Video
972:Nano-RAM
941:Memistor
914:XQD card
889:SIM card
747:Dekatron
633:XDR DRAM
628:EDO DRAM
565:Volatile
359:Hex dump
269:Database
164:Metadata
159:Big data
2250:Reticon
2151:9846847
1969:from a
1753:Mercury
1687:mercury
1677:at the
1633:display
1626:clutter
1579:latency
1526:digital
1469:(~1970)
1463:(~1968)
1445:(1960s)
1282:Blu-ray
1272:MiniDVD
1267:DVD-RAM
1227:Mini CD
1169:Optical
1129:U-matic
1124:MicroMV
1104:Betamax
968:(ECRAM)
909:MicroP2
884:SD card
874:PC Card
665:1T-SRAM
623:QDRSRAM
214:Storage
44:General
2149:
1932:Friden
1857:nickel
1822:CSIRAC
1721:(1951)
1557:and a
1475:(1971)
1457:(1962)
1451:(1962)
1439:(1957)
1433:(1949)
1427:(1932)
1416:(1725)
1410:(1725)
1404:(1725)
1277:HD DVD
1237:CD-ROM
1193:(CDDA)
1119:MiniDV
838:(SSHD)
820:(SSS)
806:EEPROM
754:(2009)
743:(1952)
737:(1951)
731:(1947)
349:Backup
2280:arXiv
2258:(PDF)
2245:(PDF)
2220:(PDF)
2209:(PDF)
2169:(PDF)
2147:S2CID
1904:tubes
1798:words
1784:EDSAC
1736:clock
1689:with
1622:radar
1590:EDVAC
1337:ECRAM
1317:CBRAM
1252:DVD+R
1212:CD-RW
1149:D-VHS
1144:VHS-C
1139:S-VHS
1080:(DDS)
1003:ReRAM
998:FeRAM
991:NVRAM
977:CBRAM
934:NVRAM
832:(SSD)
801:EPROM
758:Z-RAM
752:T-RAM
684:(CAM)
672:ReRAM
638:RDRAM
618:LPDDR
613:SGRAM
608:SDRAM
603:eDRAM
37:types
2033:and
1812:room
1567:bits
1327:NRAM
1299:WORM
1207:CD-R
961:MRAM
796:PROM
791:MROM
693:VRAM
677:QRAM
660:SRAM
648:GDDR
598:DRAM
494:RAID
144:Data
33:and
2137:doi
2067:or
2051:in
1991:PAL
1975:GDR
1971:PAL
1795:bit
1774:gin
1681:'s
1656:MIT
1247:DVD
1134:VHS
951:PCM
904:SxS
779:ROM
653:HBM
643:DDR
574:RAM
2372::
2351:.
2253:.
2247:.
2228:29
2226:.
2222:.
2171:.
2145:.
2133:15
2131:.
2127:.
1914:,
1604:,
1547:.
1197:CD
1114:DV
2288:.
2282::
2267:.
2153:.
2139::
2104:.
2055:.
2045:,
2026:,
1883:(
1503:e
1496:t
1489:v
957:)
953:(
20:)
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