1353:
DATA RADIO COMMUNICATIONS AND ELECTRONICS" The Award was presented at NAECON on May 18, 1983. Being aware of developments within the United States and shortly before the ICAO VII COM , the U.K. delegates proposed a compromise code to the United States which quantized altitude in 500 ft steps for a range of 64000 ft by employing a conventional Gray code with a 2.9 µs pulse spacing in the return message, and in a compatible manner subdivided further by 100 ft increments with a 1.45 µs pulse spacing in the return message A quick look at the U.K. proposal concluded that the United States could live with the U.K. compromise although greater circuit complexity resulted for coding and decoding. It is to the credit of the U.S. delegation to the ICAO VII COM, and as a result of the advice of Ashley, Herrmann, Perry, and others, that the acceptance of the compatible U.K. proposal was seen as offering a means of obtaining timely agreement on 100 ft increment reportings o that future air traffic control systems could be developed with automatic three dimensional data acquisition. A potential impasse in ICAO was averted, leaving nations free to choose between 100 ft and 500 ft increments of altitude reporting.
122:
276:
1245:, 1955. The QUEEN has been graciously pleased, on the occasion of the Celebration of Her Majesty's Birthday, to give orders for the following promotions in, and appointments to, the Most Excellent Order of the British Empire:— To be Ordinary Members of the Civil Division of the said Most Excellent Order:— Ronald Lionel GILLHAM, Esq., Signals Officer, Air Navigational Services, Ministry of Transport and Civil Aviation.
289:
very latest encoders incorporate unheated 'instant on' type sensors. During the warm-up of older style units the height information may gradually increase until it settles at its final value. This is not normally a problem as the power would typically be applied before the aircraft enters the runway and so it would be transmitting correct height information soon after take-off.
962:
1029:) to encode the offset from the 500 ft altitude in 100 ft increments. Specifically, if the parity of the 500 ft code is even then codes 001, 011, 010, 110 and 100 encode −200, −100, 0, +100 and +200 ft relative to the 500 ft altitude. If the parity is odd, the assignments are reversed. Codes 000, 101 and 111 are not used.
240:(IATA) committee developing the specification for the second generation of air traffic control system, known in the UK as "Plan Ahead", and is said to have had the idea of using a modified Gray code. The final code variant was developed in late 1961 for the ICAO Communications Division meeting (VII COM) held in January/February 1962, and described in a 1962
1352:
The
Pioneer Award Committee of the IEEE Aerospace and Electronic Systems Society has named Allan Ashley Joseph E. Hermann James S. Perry as recipients of the 1983 Pioneer Award in recognition of the highly significant contributions made by them. "FOR ADVANCING THE STATE OF THE ART OF VOICE AND
308:
Different classes of altitude encoder do not use all of the available bits. All use the A, B and C bits; increasing altitude limits require more of the D bits. Up to and including 30700 ft does not require any of the D bits (9-wire interface). This is suitable for most light general aviation
288:
and signal conditioning electronics. The pressure sensor is often heated, which requires a warm-up time during which height information is either unavailable or inaccurate. Older style units can have a warm-up time of up to 10 minutes; more modern units warm up in less than 2 minutes. Some of the
2255:
304:
The height information is represented as 11 binary digits in a parallel form using 11 separate lines designated D2 D4 A1 A2 A4 B1 B2 B4 C1 C2 C4. As a twelfth bit, the
Gillham code contains a D1 bit but this is unused and consequently set to zero in practical applications.
2394:
2203:, this does not give rise to particular difficulties: whenever the code word for the tens represents an odd number, the code words for the decimal units are given as the 9s complements by inversion of the fourth binary digit.
279:
A typical altitude encoder, the ACK Technologies A-30. Note the 15-way D-type connector to send the
Gillham code to the transponder and the port on the top of the case that connects to the aircraft's static pressure
2389:
2199:
within each decade, and reflected decimal numbers for the decimal transitions. For further processing, code conversion to the natural decimal notation is necessary. Since the O'Brien II code forms a
1623:. The arrangement is such that the Datex code defines the bits for the units count of the encoder and the Gray code defines the bits for each of the higher order decades, the tens, hundreds, etc
1032:
The
Gillham code can be decoded using various methods. Standard techniques use hardware or software solutions. The latter often uses a lookup table but an algorithmic approach can be taken.
225:
267:
for automatic height transmission for air traffic control purposes, the interface is now discouraged and has been mostly replaced by modern serial communication in newer aircraft.
1323:
1733:. Each has its particular merits and they are offered as options by various encoder manufacturers. A discussion of their respective merits is outside the scope of this book.
1559:
Designed to be compatible with
American and European traffic systems, a beacon encoder available from Norden Div., United Aircraft Corp., Norwalk, Conn., puts out a modified
1121:
2239:(xii+327+3 pages) (NB. The German edition of volume I was published in 1969, 1971, two editions in 1972, and 1975. Volume II was published in 1970, 1972, 1973, and 1975.)
309:
aircraft. Up to and including 62700 ft requires D4 (10-wire interface). Up to and including 126700 ft requires D4 and D2 (11-wire interface). D1 is never used.
2371:
133:
light aircraft. The transponder gets its altitude information from an encoding altimeter mounted behind the instrument panel that communicates via the
Gillham code.
2329:
2069:
1934:
1596:
1014:
Bits D2 (msbit) through B4 (lsbit) encode the pressure altitude in 500 ft increments (above a base altitude of −1000±250 ft) in a standard 8-bit
2319:
229:
1924:
203:
1041:
237:
1855:
2152:
108:
2168:
1252:
1250:
1248:
1179:
1698:
1082:
Anecdotally, Ronald Lionel
Gillham had the idea for the modified Gray code while having a family dinner. Reportedly, he died in March 1968.
1340:
2367:
2296:(3 pages) (NB. This paper was prepared for presentation at the AIEE Winter General Meeting, New York, USA, 1955-01-30 to 1955-02-03.)
1018:(Gray code). The specification stops at code 1000000 (126500±250 ft), above which D1 would be needed as a most significant bit.
2232:
2178:
2123:
2093:
2011:
1001:
1806:
248:
being coined are unclear, but by 1963 the code was already recognized under this name. By the mid-1960s the code was also known as
1394:
1890:
1661:
1639:
1108:
1047:
1730:
1403:
1375:
2404:
2250:
1745:
2358:
1836:
983:
972:
1271:
1117:
218:
1778:
2310:
2056:
1915:
1581:
1201:
2445:
2147:. Philips Technical Library (PTL) / Macmillan Education (Reprint of 1st English ed.). Eindhoven, Netherlands:
101:
1710:
1706:
1110:
Honeywell System
Installation Manual - Bendix/King KMH 880/KTA 870 Multi-Hazard Awareness Traffic Advisory System
1406:(FAA), Aviation Research And Development Service. Report 8893-SP-1. Contract FAA/BRD-329. Task 6. Archived from
2148:
1911:
1726:
1026:
2221:
Digitale
Elektronik in der Meßtechnik und Datenverarbeitung: Theoretische Grundlagen und Schaltungstechnik
171:
126:
2224:
1690:
1163:
1015:
233:
145:
130:
94:
81:
2223:. Philips Fachbücher (in German). Vol. I (improved and extended 5th ed.). Hamburg, Germany:
2256:
Transactions of the
American Institute of Electrical Engineers, Part I: Communication and Electronics
1859:
1441:
1970:
1718:
1390:
1367:
1022:
214:
1226:
1171:
121:
2280:
2117:
2029:
1799:
1299:
1283:
1266:
Ashley, Allan (December 1961). "Code Configuration for Automatic Altitude Reporting via ATCRBS".
1231:
2196:
224:
The code is named after Ronald Lionel Gillham, a signals officer at Air Navigational Services,
2450:
2272:
2228:
2206:(270 pages) (NB. This is based on a translation of volume I of the two-volume German edition.)
2164:
2141:
Dokter, Folkert; Steinhauer, Jürgen (1973-06-18). "2.4. Coding numbers in the binary system".
2087:
2017:
2007:
1995:
1974:
1962:
1694:
1680:
1543:
1499:
1491:
1450:
1291:
1175:
979:
275:
164:
2422:
1886:
2264:
2174:
2156:
1332:
1275:
1155:
63:
2398:
2041:
2003:
285:
1156:
2406:
DO-181E Minimum Operational Performance Standards for ATCRBS / Mode S Airborne Equipment
1722:
1459:
A new encoder with an output in Gillham code, as recommended for altitude encoding by
1407:
293:
2439:
2200:
1490:(9). Massachusetts, USA: Computer Design Publishing Corporation: 45. September 1963.
1167:
316:
2284:
1372:
Final Engineering Report on Evaluation of L-band Secondary Radar. For ANDB under CAA
1303:
2000:
Taschenbuch der Informatik – Band II – Struktur und Programmierung von EDV-Systemen
1058:
325:
168:
1749:
1158:
Aircraft Electrical and Electronic Systems - Principles, Operation and Maintenance
2142:
1684:
1566:
1531:
1479:
1436:
322:
141:
53:
2064:
1591:
1318:
1279:
1154:
Tooley, Mike; Wyatt, David (2009). "3.5.1 Gillham interface and Gillham code".
2324:
2192:
2160:
1929:
1840:
1616:
199:
2276:
2268:
2219:
Dokter, Folkert; Steinhauer, Jürgen (1975) . "2.4.4.6. Einschrittige Kodes".
1547:
1515:
Output code of a new Beacon encoder is known as the Gillham code, a modified
1503:
1495:
1454:
1336:
1295:
1287:
2427:
Consolidated Abstracts of Technical Reports: General distribution. 1957–1962
1612:
1560:
1516:
1063:
175:
160:
153:
1519:
designed to be compatible with both American and European traffic systems.
1770:
2391:
Annex 10 - Volume IV - Surveillance Radar and Collision Avoidance Systems
1205:
1053:
179:
156:
2417:. Deer Park, New York: Airborne Instruments Laboratory. Report 5791-23.
1396:
Height Code Tables For Use With Air Traffic Control Radar Beacon System
2263:(2). Bell Telephone Laboratories, Whippany, New Jersey, USA: 120–122.
284:
An altitude encoder takes the form of a small metal box containing a
210:
206:
1378:(FAA), Aviation Research And Development Service. Report 8893-SP-1.
1021:
Bits C1, C2 and C4 use a mirrored 5-state 3-bit Gray BCD code of a
296:
output, compatible with 14 V or 28 V electrical systems.
1665:
1643:
274:
120:
1435:
United Service and Royal Aero Club (Great Britain) (1964-04-09).
2021:
1978:
1714:
1460:
1328:
264:
1464:
955:
241:
1705:
Other forms of code are also well known. Among these are the
1542:. Technical Publishing Company: 110. January–December 1963.
1611:
The MOA-GILLHAM code is essentially the combination of the
1268:
IRE Transactions on Aerospace and Navigational Electronics
244:
report. The exact timeframe and circumstances of the term
2423:"Study of Altitude Reporting via ATC Radar Beacon System"
2251:"Cyclic Decimal Codes for Analogue to Digital Converters"
1969:(in German) (1 ed.). Berlin / Göttingen / New York:
2002:(in German). Vol. 2 (3 ed.). Berlin, Germany:
1202:"Mode A and Mode C - The straight scoop on how it works"
178:
and is sometimes referred to simply as a "Gray code" in
2415:
Study of Altitude Reporting via ATC Radar Beacon System
1990:
1988:
1830:
1828:
1826:
1324:
IEEE Transactions on Aerospace and Electronic Systems
1235:(Supplement). 1955-06-03. pp. 3267, 3272, 3274.
1195:
1193:
1191:
982:. Please help to ensure that disputed statements are
202:
system, which was introduced in the 1950s. The civil
2360:
Military Handbook: Encoders - Shaft Angle To Digital
1998:; Weber, Wolfgang; Heinemann, Traute, eds. (1974) .
1149:
1147:
1145:
1143:
1141:
80:
72:
62:
52:
44:
36:
28:
23:
2312:Circuit for converting one code into another code
2304:
2302:
1957:
1955:
1402:(Report). Deer Park, Long Island, New York, USA:
1374:(Report). Deer Park, Long Island, New York, USA:
2062:. Monrovia, California, USA: Datex Corporation.
1800:"Altitude Encoder Model 8800-T Operating Manual"
1103:
1101:
1099:
2386:(NB. Supersedes MIL-HDBK-231(AS) (1970-07-01).)
2112:. Monrovia, California, USA: Datex Corporation.
1880:
1878:
1876:
1575:
1573:
1389:Airborne Instruments Laboratory, a division of
1366:Airborne Instruments Laboratory, a division of
1237:CENTRAL CHANCERY OF THE ORDERS OF KNIGHTHOOD.
228:, who had been appointed a civil member of the
2214:
2212:
2136:
2134:
1965:, ed. (1962). Written at Karlsruhe, Germany.
129:(the beige box) in the instrument panel of an
1619:; the Datex code is disclosed in U.S. Patent
1449:(2874). Illiffe Transport Publications: 593.
1261:
1259:
102:
8:
1887:"Aviation Gray Code: Gillham Code Explained"
1120:August 2002 . Manual number 006-10609-0003.
1805:. Shadin Avionics. 2016. OP8800-TC Rev. F.
2320:VDO Tachometer Werke Adolf Schindling GmbH
1620:
1615:discussed thereinabove and the well known
1430:
1428:
230:Most Excellent Order of the British Empire
109:
95:
1925:Bell Telephone Laboratories, Incorporated
1025:type (with the first 5 states resembling
1002:Learn how and when to remove this message
1467:report of May 1962, has been introduced
978:Relevant discussion may be found on the
311:
236:. He was the UK's representative to the
226:Ministry of Transport and Civil Aviation
2057:"Digital coding and translating system"
1967:Taschenbuch der Nachrichtenverarbeitung
1713:; Gillham code which is recommended by
1095:
1075:
1042:Air traffic control radar beacon system
238:International Air Transport Association
152:, that is used to transmit uncorrected
2115:
2085:
2037:
2027:
1717:for automatic height transmission for
1658:Mark 2 Air Traffic Control Transponder
1270:. ANE-8 (4). Melville, New York, USA:
144:using a parallel nine- to eleven-wire
20:
2401:; 4th Edition; ICAO; 280 pages; 2007.
1681:"Chapter 6. Displacement measurement"
1646:). 1968-02-15. p. 55. ARINC 572.
1589:. New York, USA: Conrac Corporation.
7:
260:specified the code as well in 1968.
2368:United States Department of Defense
2153:N. V. Philips' Gloeilampenfabrieken
1839:. AirSport Avionics. Archived from
1746:"Ameriking AK-350 Altitude Encoder"
1204:. AirSport Avionics. Archived from
2309:Langheinrich, Hans (1974-04-16) .
2055:Spaulding, Carl P. (1965-01-12) .
1889:. Custom Computer Services (CCS).
1748:. Ameri-king. 2004. Archived from
1686:Instrumentation in Process Control
14:
2429:(Abstract). 1962. p. #62-45.
2108:Spaulding, Carl P. (1965-07-12).
1580:Wheeler, Edwin L. (1969-12-30) .
2413:Ashley, Allan (September 1960).
2249:O'Brien, Joseph A. (May 1956) .
1835:Phillips, Darryl (2012-07-26) .
1679:Wightman, Eric Jeffrey (2017) .
1662:Aeronautical Radio, Incorporated
1640:Aeronautical Radio, Incorporated
1048:Selective Identification Feature
960:
2377:from the original on 2020-07-25
2335:from the original on 2020-08-05
2075:from the original on 2020-08-05
1940:from the original on 2020-08-05
1893:from the original on 2018-01-16
1812:from the original on 2018-01-16
1781:from the original on 2018-01-16
1777:. ACK Technologies, Inc. 2002.
1731:National Engineering Laboratory
1636:Mark 2 Subsonic Air Data System
1602:from the original on 2020-08-05
1404:Federal Aviation Administration
1376:Federal Aviation Administration
1343:from the original on 2020-05-16
1127:from the original on 2018-01-18
339:000 000 000 001
204:transponder interrogation modes
198:are an outgrowth of the 12-bit
1771:"Model E-04 406/121.5 MHz ELT"
1595:. Serial No. 719026 (397812).
1:
2370:. 1991-09-30. MIL-HDBK-231A.
2122:: CS1 maint: date and year (
2092:: CS1 maint: date and year (
1854:D. F. S., Marc (2000-11-27).
174:. It is a modified form of a
131:American Aviation AA-1 Yankee
1638:. Annapolis, Maryland, USA:
1272:Institute of Radio Engineers
1118:Honeywell International Inc.
219:secondary surveillance radar
1858:. ForPilots. Archived from
1563:known as the Gillham code.
2467:
2155:. pp. 32, 39, 50–53.
1885:Stewart, K. (2010-12-03).
1280:10.1109/TANE3.1961.4201819
1200:Phillips, Darryl (2012) .
2161:10.1007/978-1-349-01417-0
2110:How to Use Shaft Encoders
1711:Excess Three decimal code
1707:Royal Radar Establishment
1583:Analog to digital encoder
1536:Control Engineering (CtE)
90:
2269:10.1109/TCE.1956.6372498
2149:The Macmillan Press Ltd.
1917:Pulse Code Communication
1837:"Altitude - MODEC ASCII"
1337:10.1109/TAES.1983.309363
1239:St. James's Palace, S.W.
263:Once recommended by the
140:is a zero-padded 12-bit
1727:Leslie and Russell code
1116:(Revision 3 ed.).
2328:. Application 192830.
2318:. Frankfurt, Germany:
1331:: 648–656. July 1983.
281:
134:
2325:U.S. patent 3,805,041
2225:Deutsche Philips GmbH
2068:. Serial No. 415058.
1933:. Serial No. 785697.
1930:U.S. patent 2,632,058
1856:"Single Gillham code"
1693:. pp. 122–123 .
1691:Butterworth-Heinemann
1164:Butterworth-Heinemann
1016:reflected binary code
278:
234:1955 Birthday Honours
232:(MBE) in the Queen's
125:A Cessna ARC RT-359A
124:
2409:; Rev E; RTCA; 2011.
2065:U.S. patent 3165731A
1689:(Revised ed.).
1592:U.S. patent 3487460A
1463:and described in an
1442:Flight International
1319:"1983 Pioneer Award"
1027:O'Brien code type II
971:factual accuracy is
159:between an encoding
2144:Digital Electronics
2006:. pp. 98–100.
1971:Springer-Verlag OHG
1719:air traffic control
1437:"Altitude encoding"
1391:Cutler-Hammer, Inc.
1368:Cutler-Hammer, Inc.
1023:Giannini Datex code
292:The encoder has an
215:air traffic control
2397:6 May 2014 at the
1996:Steinbuch, Karl W.
1973:. pp. 71–74.
1963:Steinbuch, Karl W.
1232:The London Gazette
282:
135:
2446:Data transmission
2170:978-1-349-01419-4
1923:. New York, USA:
1181:978-0-7506-8695-2
1012:
1011:
1004:
949:
948:
254:ICAO–Gillham code
192:Gillham interface
165:air data computer
150:Gillham interface
119:
118:
2458:
2430:
2418:
2385:
2383:
2382:
2376:
2365:
2345:
2343:
2341:
2340:
2334:
2327:
2317:
2306:
2297:
2295:
2293:
2292:
2246:
2240:
2238:
2216:
2207:
2205:
2188:
2187:
2138:
2129:
2127:
2121:
2113:
2105:
2099:
2097:
2091:
2083:
2081:
2080:
2074:
2067:
2061:
2052:
2046:
2045:
2039:
2035:
2033:
2025:
1992:
1983:
1982:
1959:
1950:
1948:
1946:
1945:
1939:
1932:
1922:
1908:
1902:
1901:
1899:
1898:
1882:
1871:
1870:
1868:
1867:
1851:
1845:
1844:
1832:
1821:
1820:
1818:
1817:
1811:
1804:
1796:
1790:
1789:
1787:
1786:
1767:
1761:
1760:
1758:
1757:
1742:
1736:
1735:
1700:978-1-48316335-2
1676:
1670:
1669:
1654:
1648:
1647:
1632:
1626:
1625:
1608:
1607:
1601:
1594:
1588:
1577:
1568:
1565:
1556:
1555:
1550:. (344) or (345)
1528:
1522:
1521:
1512:
1511:
1506:. Circle No. 169
1480:"Beacon Encoder"
1476:
1470:
1469:
1432:
1423:
1421:
1419:
1418:
1412:
1401:
1386:
1380:
1379:
1363:
1357:
1355:
1349:
1348:
1315:
1309:
1307:
1263:
1254:
1247:
1223:
1217:
1216:
1214:
1213:
1197:
1186:
1185:
1161:
1151:
1136:
1135:
1133:
1132:
1126:
1115:
1105:
1083:
1080:
1007:
1000:
996:
993:
987:
984:reliably sourced
964:
963:
956:
937:010 000 000 001
924:010 000 000 011
911:010 000 000 010
898:010 000 000 110
871:000 000 100 001
858:000 000 100 011
845:000 000 100 010
832:000 000 100 110
819:000 000 100 100
806:000 000 101 100
793:000 000 101 110
780:000 000 101 010
767:000 000 101 011
754:000 000 101 001
741:000 000 111 001
728:000 000 111 011
715:000 000 111 010
702:000 000 111 110
689:000 000 111 100
675:000 000 110 100
661:000 000 110 110
647:000 000 110 010
633:000 000 110 011
619:000 000 110 001
605:000 000 010 001
591:000 000 010 011
577:000 000 010 010
563:000 000 010 110
549:000 000 010 100
535:000 000 011 100
521:000 000 011 110
507:000 000 011 010
493:000 000 011 011
479:000 000 011 001
465:000 000 001 001
451:000 000 001 011
437:000 000 001 010
423:000 000 001 110
409:000 000 001 100
395:000 000 000 100
381:000 000 000 110
367:000 000 000 010
353:000 000 000 011
312:
271:Altitude encoder
250:MOA–Gillham code
213:were defined in
111:
104:
97:
73:Maximum distance
64:Minimum distance
21:
2466:
2465:
2461:
2460:
2459:
2457:
2456:
2455:
2436:
2435:
2421:
2412:
2399:Wayback Machine
2380:
2378:
2374:
2363:
2357:
2354:
2352:Further reading
2349:
2348:
2338:
2336:
2332:
2323:
2315:
2308:
2307:
2300:
2290:
2288:
2248:
2247:
2243:
2235:
2218:
2217:
2210:
2197:O'Brien code II
2185:
2183:
2181:
2171:
2140:
2139:
2132:
2114:
2107:
2106:
2102:
2084:
2078:
2076:
2072:
2063:
2059:
2054:
2053:
2049:
2036:
2026:
2014:
2004:Springer Verlag
1994:
1993:
1986:
1961:
1960:
1953:
1943:
1941:
1937:
1928:
1920:
1914:(1953-03-17) .
1910:
1909:
1905:
1896:
1894:
1884:
1883:
1874:
1865:
1863:
1853:
1852:
1848:
1834:
1833:
1824:
1815:
1813:
1809:
1802:
1798:
1797:
1793:
1784:
1782:
1769:
1768:
1764:
1755:
1753:
1744:
1743:
1739:
1701:
1678:
1677:
1673:
1668:). ARINC 572-1.
1656:
1655:
1651:
1634:
1633:
1629:
1605:
1603:
1599:
1590:
1586:
1579:
1578:
1571:
1553:
1551:
1530:
1529:
1525:
1509:
1507:
1484:Computer Design
1478:
1477:
1473:
1434:
1433:
1426:
1416:
1414:
1410:
1399:
1388:
1387:
1383:
1365:
1364:
1360:
1346:
1344:
1317:
1316:
1312:
1265:
1264:
1257:
1225:
1224:
1220:
1211:
1209:
1199:
1198:
1189:
1182:
1153:
1152:
1139:
1130:
1128:
1124:
1113:
1107:
1106:
1097:
1092:
1087:
1086:
1081:
1077:
1072:
1038:
1008:
997:
991:
988:
977:
969:This section's
965:
961:
954:
302:
286:pressure sensor
273:
221:(SSR) in 1960.
188:
115:
17:
12:
11:
5:
2464:
2462:
2454:
2453:
2448:
2438:
2437:
2434:
2433:
2432:
2431:
2410:
2402:
2387:
2353:
2350:
2347:
2346:
2298:
2241:
2233:
2227:. p. 60.
2208:
2189:. p. 53:
2179:
2169:
2130:
2100:
2047:
2012:
1984:
1951:
1903:
1872:
1846:
1843:on 2012-07-26.
1822:
1791:
1762:
1737:
1723:Petherick code
1721:purposes; the
1699:
1671:
1649:
1627:
1569:
1532:"New Products"
1523:
1471:
1424:
1381:
1370:(1962-05-19).
1358:
1327:. AES-19 (4).
1310:
1255:
1218:
1187:
1180:
1162:(1 ed.).
1137:
1094:
1093:
1091:
1088:
1085:
1084:
1074:
1073:
1071:
1068:
1067:
1066:
1061:
1056:
1051:
1045:
1037:
1034:
1010:
1009:
968:
966:
959:
953:
950:
947:
946:
943:
941:
938:
934:
933:
930:
928:
925:
921:
920:
917:
915:
912:
908:
907:
904:
902:
899:
895:
894:
891:
888:
885:
881:
880:
877:
875:
872:
868:
867:
864:
862:
859:
855:
854:
851:
849:
846:
842:
841:
838:
836:
833:
829:
828:
825:
823:
820:
816:
815:
812:
810:
807:
803:
802:
799:
797:
794:
790:
789:
786:
784:
781:
777:
776:
773:
771:
768:
764:
763:
760:
758:
755:
751:
750:
747:
745:
742:
738:
737:
734:
732:
729:
725:
724:
721:
719:
716:
712:
711:
708:
706:
703:
699:
698:
695:
693:
690:
686:
685:
682:
679:
676:
672:
671:
668:
665:
662:
658:
657:
654:
651:
648:
644:
643:
640:
637:
634:
630:
629:
626:
623:
620:
616:
615:
612:
609:
606:
602:
601:
598:
595:
592:
588:
587:
584:
581:
578:
574:
573:
570:
567:
564:
560:
559:
556:
553:
550:
546:
545:
542:
539:
536:
532:
531:
528:
525:
522:
518:
517:
514:
511:
508:
504:
503:
500:
497:
494:
490:
489:
486:
483:
480:
476:
475:
472:
469:
466:
462:
461:
458:
455:
452:
448:
447:
444:
441:
438:
434:
433:
430:
427:
424:
420:
419:
416:
413:
410:
406:
405:
402:
399:
396:
392:
391:
388:
385:
382:
378:
377:
374:
371:
368:
364:
363:
360:
357:
354:
350:
349:
346:
343:
340:
336:
335:
332:
329:
320:
301:
298:
294:open-collector
272:
269:
187:
184:
117:
116:
114:
113:
106:
99:
91:
88:
87:
84:
78:
77:
74:
70:
69:
66:
60:
59:
56:
50:
49:
46:
42:
41:
38:
34:
33:
30:
26:
25:
15:
13:
10:
9:
6:
4:
3:
2:
2463:
2452:
2449:
2447:
2444:
2443:
2441:
2428:
2424:
2420:
2419:
2416:
2411:
2408:
2407:
2403:
2400:
2396:
2393:
2392:
2388:
2373:
2369:
2362:
2361:
2356:
2355:
2351:
2331:
2326:
2321:
2314:
2313:
2305:
2303:
2299:
2287:. Paper 56-21
2286:
2282:
2278:
2274:
2270:
2266:
2262:
2258:
2257:
2252:
2245:
2242:
2236:
2234:3-87145-272-6
2230:
2226:
2222:
2215:
2213:
2209:
2204:
2202:
2201:9s complement
2198:
2194:
2182:
2176:
2172:
2166:
2162:
2158:
2154:
2150:
2146:
2145:
2137:
2135:
2131:
2125:
2119:
2111:
2104:
2101:
2095:
2089:
2071:
2066:
2058:
2051:
2048:
2043:
2031:
2023:
2019:
2015:
2013:3-540-06241-6
2009:
2005:
2001:
1997:
1991:
1989:
1985:
1980:
1976:
1972:
1968:
1964:
1958:
1956:
1952:
1936:
1931:
1926:
1919:
1918:
1913:
1907:
1904:
1892:
1888:
1881:
1879:
1877:
1873:
1862:on 2018-01-17
1861:
1857:
1850:
1847:
1842:
1838:
1831:
1829:
1827:
1823:
1808:
1801:
1795:
1792:
1780:
1776:
1772:
1766:
1763:
1752:on 2016-06-25
1751:
1747:
1741:
1738:
1734:
1732:
1728:
1724:
1720:
1716:
1712:
1708:
1702:
1696:
1692:
1688:
1687:
1682:
1675:
1672:
1667:
1663:
1659:
1653:
1650:
1645:
1641:
1637:
1631:
1628:
1624:
1622:
1618:
1614:
1598:
1593:
1585:
1584:
1576:
1574:
1570:
1567:
1564:
1562:
1549:
1545:
1541:
1537:
1533:
1527:
1524:
1520:
1518:
1505:
1501:
1497:
1493:
1489:
1485:
1481:
1475:
1472:
1468:
1466:
1462:
1456:
1452:
1448:
1444:
1443:
1438:
1431:
1429:
1425:
1413:on 2020-05-17
1409:
1405:
1398:
1397:
1392:
1385:
1382:
1377:
1373:
1369:
1362:
1359:
1354:
1342:
1338:
1334:
1330:
1326:
1325:
1320:
1314:
1311:
1305:
1301:
1297:
1293:
1289:
1285:
1281:
1277:
1273:
1269:
1262:
1260:
1256:
1253:
1251:
1249:
1246:
1244:
1240:
1234:
1233:
1228:
1222:
1219:
1208:on 2012-06-14
1207:
1203:
1196:
1194:
1192:
1188:
1183:
1177:
1173:
1169:
1168:Elsevier Ltd.
1165:
1160:
1159:
1150:
1148:
1146:
1144:
1142:
1138:
1123:
1119:
1112:
1111:
1104:
1102:
1100:
1096:
1089:
1079:
1076:
1069:
1065:
1062:
1060:
1057:
1055:
1052:
1049:
1046:
1043:
1040:
1039:
1035:
1033:
1030:
1028:
1024:
1019:
1017:
1006:
1003:
995:
985:
981:
975:
974:
967:
958:
957:
951:
944:
942:
939:
936:
935:
931:
929:
926:
923:
922:
918:
916:
913:
910:
909:
905:
903:
900:
897:
896:
892:
889:
886:
883:
882:
878:
876:
873:
870:
869:
865:
863:
860:
857:
856:
852:
850:
847:
844:
843:
839:
837:
834:
831:
830:
826:
824:
821:
818:
817:
813:
811:
808:
805:
804:
800:
798:
795:
792:
791:
787:
785:
782:
779:
778:
774:
772:
769:
766:
765:
761:
759:
756:
753:
752:
748:
746:
743:
740:
739:
735:
733:
730:
727:
726:
722:
720:
717:
714:
713:
709:
707:
704:
701:
700:
696:
694:
691:
688:
687:
683:
680:
677:
674:
673:
669:
666:
663:
660:
659:
655:
652:
649:
646:
645:
641:
638:
635:
632:
631:
627:
624:
621:
618:
617:
613:
610:
607:
604:
603:
599:
596:
593:
590:
589:
585:
582:
579:
576:
575:
571:
568:
565:
562:
561:
557:
554:
551:
548:
547:
543:
540:
537:
534:
533:
529:
526:
523:
520:
519:
515:
512:
509:
506:
505:
501:
498:
495:
492:
491:
487:
484:
481:
478:
477:
473:
470:
467:
464:
463:
459:
456:
453:
450:
449:
445:
442:
439:
436:
435:
431:
428:
425:
422:
421:
417:
414:
411:
408:
407:
403:
400:
397:
394:
393:
389:
386:
383:
380:
379:
375:
372:
369:
366:
365:
361:
358:
355:
352:
351:
347:
344:
341:
338:
337:
333:
330:
327:
324:
321:
318:
314:
313:
310:
306:
299:
297:
295:
290:
287:
277:
270:
268:
266:
261:
259:
255:
251:
247:
243:
239:
235:
231:
227:
222:
220:
216:
212:
208:
205:
201:
197:
193:
185:
183:
181:
177:
173:
170:
166:
162:
158:
155:
151:
147:
143:
139:
132:
128:
123:
112:
107:
105:
100:
98:
93:
92:
89:
85:
83:
79:
75:
71:
67:
65:
61:
57:
55:
51:
47:
43:
39:
35:
31:
27:
22:
19:
2426:
2414:
2405:
2390:
2379:. Retrieved
2359:
2337:. Retrieved
2311:
2289:. Retrieved
2260:
2254:
2244:
2220:
2190:
2184:. Retrieved
2143:
2109:
2103:
2077:. Retrieved
2050:
1999:
1966:
1942:. Retrieved
1916:
1906:
1895:. Retrieved
1864:. Retrieved
1860:the original
1849:
1841:the original
1814:. Retrieved
1794:
1783:. Retrieved
1774:
1765:
1754:. Retrieved
1750:the original
1740:
1704:
1685:
1674:
1657:
1652:
1635:
1630:
1610:
1604:. Retrieved
1582:
1558:
1552:. Retrieved
1539:
1535:
1526:
1514:
1508:. Retrieved
1487:
1483:
1474:
1458:
1446:
1440:
1415:. Retrieved
1408:the original
1395:
1393:(May 1962).
1384:
1371:
1361:
1351:
1345:. Retrieved
1322:
1313:
1267:
1242:
1238:
1236:
1230:
1221:
1210:. Retrieved
1206:the original
1157:
1129:. Retrieved
1109:
1078:
1059:Flight level
1031:
1020:
1013:
998:
989:
970:
307:
303:
291:
283:
262:
257:
253:
249:
246:Gillham code
245:
223:
195:
191:
189:
182:literature.
149:
138:Gillham code
137:
136:
82:Lexicography
24:Gillham code
18:
2180:333-13360-9
2038:|work=
1912:Gray, Frank
1274:: 144–148.
1227:"No. 40497"
1170:). p.
992:August 2022
172:transponder
142:binary code
127:transponder
16:Binary code
2440:Categories
2381:2020-07-25
2339:2018-01-14
2291:2020-05-18
2193:Datex code
2186:2020-05-11
2128:(85 pages)
2098:(28 pages)
2079:2018-01-21
1949:(13 pages)
1944:2020-08-05
1897:2018-01-14
1866:2018-01-17
1816:2018-01-14
1785:2018-01-14
1756:2018-01-14
1725:, and the
1709:code; The
1617:Datex code
1606:2018-01-21
1554:2018-01-16
1510:2018-01-16
1422:(43 pages)
1417:2020-05-17
1347:2020-05-16
1212:2018-01-14
1131:2018-01-18
1090:References
217:(ATC) and
200:IFF Mark X
163:or analog
154:barometric
45:Continuity
2344:(7 pages)
2277:0097-2452
2195:uses the
2118:cite book
2040:ignored (
2030:cite book
1621:3,165,731
1613:Gray code
1561:Gray code
1548:0010-8049
1517:Gray code
1504:802774218
1496:0010-4566
1455:0015-3710
1356:(9 pages)
1308:(5 pages)
1296:0096-1647
1288:2331-0812
1064:ARINC 429
980:talk page
258:ARINC 572
176:Gray code
161:altimeter
146:interface
2451:Avionics
2395:Archived
2372:Archived
2330:Archived
2285:51657314
2088:cite web
2070:Archived
2022:73-80607
1979:62-14511
1935:Archived
1891:Archived
1807:Archived
1779:Archived
1775:Products
1597:Archived
1341:Archived
1304:51647765
1243:9th June
1122:Archived
1054:IFF code
1044:(ATCRBS)
1036:See also
973:disputed
952:Decoding
457:−121.92
429:−182.88
415:−213.36
401:−243.84
387:−274.32
359:−335.28
345:−365.76
334:Height
331:Height
315:Gillham
180:avionics
157:altitude
1729:of the
945:126700
932:126600
919:126500
906:126400
681:365.76
667:335.28
639:274.32
625:243.84
611:213.36
597:182.88
569:121.92
499:−30.48
485:−60.96
471:−91.44
443:−152.4
373:−304.8
280:system.
186:History
169:digital
2283:
2275:
2231:
2177:
2167:
2020:
2010:
1977:
1697:
1546:
1502:
1494:
1453:
1302:
1294:
1286:
1178:
653:304.8
583:152.4
555:91.44
541:60.96
527:30.48
376:−1000
362:−1100
348:−1200
328:code
323:Squawk
319:code
317:binary
300:Coding
167:and a
148:, the
54:Cyclic
37:Tracks
29:Digits
2375:(PDF)
2364:(PDF)
2333:(PDF)
2316:(PDF)
2281:S2CID
2073:(PDF)
2060:(PDF)
1938:(PDF)
1921:(PDF)
1810:(PDF)
1803:(PDF)
1666:ARINC
1644:ARINC
1600:(PDF)
1587:(PDF)
1411:(PDF)
1400:(PDF)
1300:S2CID
1284:eISSN
1125:(PDF)
1114:(PDF)
1070:Notes
1050:(SIF)
940:0042
927:0062
914:0022
901:0032
879:2700
874:0140
866:2600
861:0160
853:2500
848:0120
840:2400
835:0130
827:2300
822:0110
814:2200
809:0510
801:2100
796:0530
788:2000
783:0520
775:1900
770:0560
762:1800
757:0540
749:1700
744:0740
736:1600
731:0760
723:1500
718:0720
710:1400
705:0730
697:1300
692:0710
684:1200
678:0310
670:1100
664:0330
656:1000
650:0320
636:0360
622:0340
608:0240
594:0260
580:0220
566:0230
552:0210
538:0610
524:0630
510:0620
502:−100
496:0660
488:−200
482:0640
474:−300
468:0440
460:−400
454:0460
446:−500
440:0420
432:−600
426:0430
418:−700
412:0410
404:−800
398:0010
390:−900
384:0030
370:0020
356:0060
342:0040
326:octal
40:9..11
2273:ISSN
2229:ISBN
2191:The
2165:ISBN
2124:link
2094:link
2042:help
2018:LCCN
2008:ISBN
1975:LCCN
1715:ICAO
1695:ISBN
1544:ISSN
1500:OCLC
1492:ISSN
1461:ICAO
1451:ISSN
1329:IEEE
1292:ISSN
1241:1.
1176:ISBN
642:900
628:800
614:700
600:600
586:500
572:400
558:300
544:200
530:100
265:ICAO
209:and
196:code
194:and
190:The
2265:doi
2175:SBN
2157:doi
1465:FAA
1333:doi
1276:doi
252:or
242:FAA
58:yes
2442::
2425:.
2366:.
2322:.
2301:^
2279:.
2271:.
2261:75
2259:.
2253:.
2211:^
2173:.
2163:.
2151:/
2133:^
2120:}}
2116:{{
2090:}}
2086:{{
2034::
2032:}}
2028:{{
2016:.
1987:^
1954:^
1927:.
1875:^
1825:^
1773:.
1703:.
1683:.
1660:.
1609:.
1572:^
1557:.
1540:10
1538:.
1534:.
1513:.
1498:.
1486:.
1482:.
1457:.
1447:85
1445:.
1439:.
1427:^
1350:.
1339:.
1321:.
1298:.
1290:.
1282:.
1258:^
1229:.
1190:^
1174:.
1172:69
1140:^
1098:^
893:…
890:…
887:…
884:…
516:0
513:0
256:.
86:no
48:no
32:12
2384:.
2342:.
2294:.
2267::
2237:.
2159::
2126:)
2096:)
2082:.
2044:)
2024:.
1981:.
1947:.
1900:.
1869:.
1819:.
1788:.
1759:.
1664:(
1642:(
1488:2
1420:.
1335::
1306:.
1278::
1215:.
1184:.
1166:(
1134:.
1005:)
999:(
994:)
990:(
986:.
976:.
211:C
207:A
110:e
103:t
96:v
76:1
68:1
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
