engineered by Tom. gridlocw grid locator for windows in the pascal-based environment of delphi. Whether you need to drive, walk, or take public transportation, MapQuest can help you get there faster and easier. Geog is a suite of programs written by Andy Talbot. You don't have to use a hi-res picture, it will be scaled to 600x600 pixels anyway. VOACAP Online HF PredictionsNew and updated data is shown on the map in real time without need to reload or refresh the page! Tracking data is stored in the database for six months. It has been developed for a course on Visual Basic as an example. Radioamateurs du Dpt. The QRA amplitude A ˜ 7 ≈ (4. 2023 / 01:09. Michael gave his QRA locator as KN20HS. height = ln (HAAT/10) (ln = log neperian) In both cases, choose the closest value. This link is listed in our web site directory since Sunday Nov 25 2001, and till today "EZ QRA Locator" has been followed. 00) In the Uv88_SoftWare_Eng subdirectory, edit the configuration file setting. This link is listed in our web site directory since Sunday Sep 5 2010, and till today " SK6AW Maidenhead Locator Conversion " has been followed for a total of 1133 times. gridlocw grid locator for windows in the pascal-based environment of delphi. Grid Locator Intro Home > Ham Maps > Grid Locator > Intro • This page introduces the world Grid Locator system, and discusses how to find out what your own Grid Locator is. 8 within the midlatitude waveguide whose boundaries are shown by the vertical solid lines in B. Find and install UV-88 software (default in C:/UV88 V1. You can zoom the map with the help of the mouse wheel or the control on the upper left part. Sporadic-E clouds. They are embedded within the Swanwick Centre run by NATS, the UK’s main civil air services provider. Point cursor on the map and choose the sectors column AA-AR etc. You can also use this service to find your QTH/QRA locator (or your grid square) by simply pointing at a location on the map. 2. Permissions beyond the scope of this license may be available at. 281). So far. This calculator works for all locations in the United Kingdom. HTF. speaker/headphones without using browserFor example, QRA locator map for VHF/UHF contest. To find your QTH locator, click on your location on the map. Powered by OpenStreetMap/Leaflet and HeyWhatsThat Path Profiler. From now on, the Leaflet API and free basemaps are used. Summits on the Air Mapping Page offers a dynamic, zoomable Locator grid map. flat earth's curvature. Azimuth Map with HAM prefixes Version 1. [1] Its purpose is to be concise, accurate, and robust in the face of interference and. Leaflet | Map tiles by Carto, under CC BY 3. The data values for power, height, gain, dir can be converted using the table below, or they can be calculated: power = the square root of your power. The data values for power, height, gain, dir can be converted using the table below, or they can be calculated: power = the square root of your power. QRA locator map; Carte RS Europe; Circular SWR ruler; APRS; Arduino. gridlocw grid locator for windows in the pascal-based environment of delphi. gridlocw grid locator for windows in the pascal-based environment of delphi. To successfully run the application, you must give your device permission to determine your location, turn on GPS. The main reason is pure convenience. Geog UK terrain heights. HTF offer : two radio amateur wall maps with a choice of options and sizes. This was the QRA-Locator system, devised in Germany, originally based on a two-stage sub-division of geographical longitudes and latitudes starting from the Greenwich meridian and from 40 degrees North. Advanced Member. HTF. a. Geog is a suite of programs written by Andy Talbot. Northern Gas Networks, 1st Floor, 1 Emperor Way, Doxford International Business Park, Sunderland. There have been several evolutions since, with a peak activity of a dozen repeaters ! By now, only 5 are currently active. XBS-TELECOM. Address Radio Society of Great Britain 3 Abbey Court Fraser Road Priory Business Park MK44 3WH United Kingdom. It also allows to send DX-Spots and more features. The last QRA locator map no longer uses any API functions or Google maps. Read user reviews (1) World Grid Square QRA Locator Map for Radioamateurs, ideal for the shack. Esempio il QTH locator di Savona (Italia) è JN44FH. However, this ambiguity is unlikely to be a nuisance to. The data values for power, height, gain, dir can be converted using the table below, or they can be calculated: power = the square root of your power. - search by address, location. - search by address, location. Con tale termine, che sostituisce quello di QRA Locator e di QTH Locator, si intende un sistema per individuare la posizione geografica (un'area e non un preciso punto geografico) di una certa località del globo o nel nostro caso di una stazione radioamatoriale. The gateway appears on APRS maps like . More information on how to create your own application, use hi-res picture or include WRC in other applications will followEuropean QRA Locator Map (V3) for Radioamateurs, ideal for the shack. / OSM / Profile ZL: 7. Great Circles & QRA Locator. Azimuthal Map полушарие, с указаниемNØUK's Maidenhead Grid Distance & Bearing Calculator. gridlocw grid locator for windows in the pascal-based environment of delphi. Size. Geog UK terrain heights. Réseau des Émetteurs Français. Enter any address, city & state or zip: Find your QTH locator (or your grid square) with GoogleMaps. At the Region 1 Conference in Malmo (1963) the system was refined by introducing a third sub-division, and in its final form the QRA-Locator. 4 square vertical system. OF_1. (Note: The images online are not in HD to avoid slow loading pages. Maidenhead/QTH Grid Square Locator - K7FRY. GcmWin Great Circle Map. (In some cases, squares adjacent to a Grid Zone Junction (GZJ) are clipped, so polygon is a better. / OSM / Profile ZL: 7. Réseau des Émetteurs Français. Interactive World Map. Maps. You can use this page to convert your IARU QRA Locator into normal Latitude and Longitude figures. Argus. You can also use this service to find your QTH/QRA locator (or your grid square) by simply pointing at a location on the map. Summaries 144 MHz in Europe. You can enter your location in decimal degrees or degrees, minutes, second! If you don't know your station's Latitude and. The QRA locator, also called QTH locator in some publications, is an obsolete geographic coordinate system used by amateur radio operators in Europe before the introduction of the Maidenhead Locator System. On the top of the map there is a box showing the coordinates and locator currently under the mouse pointer, a controls to switch between different map layers (street map, terrain map, satellite images and hybrid satellite+street map), and a control to enable additional layers on top of the map (traffic info, bicycle routes, and so forth). Reputational Risk: Vote with your wallet folks; don’t support companies promoting anti-democratic behaviours & hate. 00 European QRA Locator Map (V1) for Radioamateurs, ideal for the shack. 281). Its purpose is to be concise, accurate, and robust in the face of interference and other adverse transmission conditions. For example, QRA locator map for VHF/UHF contest. World Grid Square Map PDF. Quick Reaction Alert QRA Nuclear Atomic Weapons Pershing Warhead Storage Waldstetten Schwabisch Gmund US 41st Field Artillery Germany Abandoned Bunker . I therefore modified my scripts to use the Openstreetmap maps which are beautiful and detailed. Calulate locator,etc. Please note that the old system is also indicated. DX-Sherlock - QSO real time maps and listings - Shows QSO and SWL in real time, taking data from many different sources (DX-Cluster, WSPR, Reverse Beacon). XBS-TELECOM. Amateur Radio Ham Radio Maidenhead Grid Square Locator Map. For instance, PX square could be either in Iceland or Turkey. Joined: Tue Sep 19, 2017 2:09 pm Posts: 316 Location: Llandeilo IO71. A locator is essentially a map reference, allowing the position of a station to be easily and concisely transmitted. This link is listed in our web site directory since Sunday Dec 25 2005, and till today " Great Circles & QRA Locator Online " has been followed for a total of 3717 times. Listed under the Operating Aids/Grid Squares category that is about Grid square locators. OF_1. Please consider donating to help keep this page active. 4GHz and a downlink on 100GHz and was a joint project between the Qatar Satellite Company, Qatar ARS and AMSAT (Deutschland). Ein Funkamateur kann seinen „QTH“ angeben, um seinen Standort oder den Standort seiner Funkstation zu beschreiben. It uses a string of two capital letters, two numerical digits and one lower case letter to mark an area of two degrees longitude by one degree latitude. Salons-Concours etc. 1959 a code system was adopted for giving the location of a station. Rand Airport (QRA) located in Johannesburg, Gauteng, South Africa. SCP map Europe; SCP map Poland; Arduino. HTF. Rerun the NØUK Maidenhead Grid Distance & Bearing Calculator. Find your Maidenhead Locator (Gridsquare) or Worked All Britain Square by using your postal address. For example, the entrance to the elevator of the Eiffel Tower in Paris is “France 4J. Find your locator by exploring the map or by searching an address. k. eg. Once the HAAT value is obtained, it must be converted to feet (feet = m x 3. There are three regional IARU organizations corresponding to the three ITU Radio Regions: Region 1 — Africa, Europe, Middle East, and northern Asia. Can someone tell me why qra location was changed to maidenhead? D Sorted. Telnet access to DX Clusters and Reverse Beacon Network (RBN) CW, RTTY Skimmer: dxcluster. GridLocW - a Lat/Long. Move the mouse over the map and this page will show you the Maidenhead locator, latitude/longitude coordinates in WGS84 (both decimal and DMS), UTM as well as french Lambert II and DFCI. TK5EP's QRA locator (and more) map. k. See also World , Canada&Alaska, USA , Central America, South Amerika, South Africa , Afrika, NorthAfrica , Europe (small), Europe (big) , Germany (small), Germany (big), former USSR, South Asia, Australia&SEAsia . €13. Maps. Maidenhead Locator Latitude Longitude. Great Circles & QRA Locator. The typical procedure to perform a QRA consists of the following steps: Identify relevant activities, units, and processes. XBS-TELECOM. This link is listed in our web site directory since Wednesday Jan 8 2020, and till today " Interactive Ham Radio Locator Map " has been followed for a total of 1336 times. QRA Locator Map and this item does two jobs in one. You must at first set your home location ! To do this, move the cursor to your home location, click on the map and a dialog box will open. If you’re creating a map about a hilly area, it’s helpful to show a shaded relief. Add to cart HAM Wall Maps. 80/10About QRA to Lat/Long converter The resource is currently listed in dxzone. Originally, digital transmission was carried out using the Packet radio protocol. k. LOCATION. Joined: Fri Sep 14, 2012 5:32 pm Posts: 5666 Location: Salisbury, Wiltshire. a. Un utilitaire sympa: -Entrez votre locator en haut à gauche et ensuite déplacer le pointeur rouge ou bien renseignez le locator pour le situer >> dans la case du milieu " situer un locator " F6HFH. The use of thirty alphanumeric characters instead of only ten digits makes a NAC shorter than its numerical latitude / longitude equivalent. Move the mouse over the map and this page will show you the Maidenhead locator, latitude/longitude coordinates in WGS84 (both decimal and DMS), UTM as well as french. For example: if the QRA locator is KN29AU then sector is KN. We would like to show you a description here but the site won’t allow us. You don't have to use a hi-res picture, it will be scaled to 600x600 pixels anyway. It plots the QSOs in a Cabrillo-format contest-log on to one of 8 different maps by finding the position of each QSO from an online database of about 970,000 W/VE callsigns. Salons-Concours etc. It is on board the Es-hail-2 satellite which was launched in 2018. QRA-L ocator map, while at the Region 1 Conference in Scheveningen the system was re-baptised with the more appropriate name QTH-Locator. K3NG Keyer; K3NG rotator Ethernet; K3NG rotator for HAM IV; K3NG rotator universal interface; Arduino and SIM800L; Station météo; HX711 mesure de poids; Economiser de la SRAM ! Arduino & SIM900; Arduino et mesure de tension; USB audio. Distributeur Matériel OM. - The IP address assigned to. The United States usually refers to Quick Reaction Alert as 'Airspace Control Alert'. €12. - a tool for measuring distance and azimuthNew and updated data is shown on the map in real time without need to reload or refresh the page! Tracking data is stored in the database for six months. Imp. GcmWin Great Circle Map. Position MyHomeQTH. )Two standard sizes are available : Small :. For example, QRA locator map for VHF/UHF contest. Summaries 144 MHz in Europe. Maps. The transmit frequency can be the same (simplex) or different (duplex) from the receive frequency. The data values for power, height, gain, dir can be converted using the table below, or they can be calculated: power = the square root of your power. com is pretty a safe domain. VHF Handbook 9. This link is listed in our web site directory since Monday Aug 8 2011, and till today "QRA Calculator" has been followed for a total of 730 times. The "or. height = ln (HAAT/10) (ln = log neperian) In both cases, choose the closest value. 3. The data values for power, height, gain, dir can be converted using the table below, or they can be calculated: power = the square root of your power. QSL_PP. Home > . New features have been added, such as: - search by QRA locator on 6 or 8 characters. AOR, YAESU, COMET. We would like to show you a description here but the site won’t allow us. Natural Area Code. eu) A valid contest QSO The Maidenhead Locator System (a. This was the QRA-Locator system, devised in Germany, originally based on a two-stage sub-division of geographical longitudes and latitudes starting from the Greenwich meridian and from 40 degrees North. QRA locator map; Carte RS Europe; Circular SWR ruler; APRS; Arduino. 77. Entering a QTH locator in the search box will move the map to the. Country List. This help content & information General Help Center experience. 14 Economy QSL cards. In accordance with Google Safe Browsing and Symantec qra-locator-map. British Virgin Islands – See Virgin Islands (British) . Login is required for additional detail. 5 ± 1. The system can describe any location in the world. 002 degrees latitude and longitude to allow for multiple stations to be. on a planar surface created by a particular map projection. Finally comes the rest for the 40m, so 20,20 m - 14,07 m = 6,13 m. Search. Originally, digital transmission was carried out using the Packet radio. Click on the map to select a grid square, or, enter desired location. 77. Its purpose is to be concise, accurate and robust in the face of interference and adverse. Democratic People's Republic of Korea – See Korea. 2023 / 14:31. / Position MyTempQTH. The QRA locator is considered defunct, but may be found in some older documents. *Locator is defined by the ADIF standard as "the logging station's 2-character, 6-character, or 8-character Maidenhead Grid Square. WW locator : JN42le38 Altitude : 1511 m 16 QSO 40/20 CW- 1 S2S. Imp. gin" of the system (ie the southwest corner or AA square) is 400 N, 00 E. DR2W. program to make Great Circle maps from any location. QTH-Locator-Systeme wurden von Funkamateuren entwickelt und werden im Amateurfunk im UKW-Funkverkehr und. Accueil; Images de thèmes de Maliketh. Argus d'avril 2020. 00. The last QRA locator map no longer uses any API functions or Google maps. com in a single category. 77. The main category is Grid square locators that is about Amateur radio grid squares. au. Setting the locator (grid) here configures this value into all other. 09:00:29, TREKANTEN TEMP QTH. The EZ QRA Locator softawre is a simple software for the calculation Great Circles & QRA Locator: Great circles qra locator map. You can also use this service to find your QTH/QRA locator (or your grid square) by simply pointing at a location on the map. 400 rettangoli con una dimensione immaginaria di 9260 metri (= 1852 x 5) di larghezza e 4630 metri (= 1852 x 2,5) d’altezza. Pages. Runways: ca. Radioamateurs du Dpt. / Position MyTempQTH. a. 6) m s −1 matches well the observed A ˜ 7, o b s ≈ (4. Having been inactive for 35 years I am now trying to get used to the new Maidenhead locator system, I was brought up on QRA Locators with a 5-character structure, which doesn't seem to be. There are several repeaters over Corsica. QRA Locator Wall Map Europe Version 3. General information include capital of South Africa, currency and conversion rate of South Africa currency, Telephone Country code, exchange rate against US Dollar and Euro. - new Maidenhead locator grid display with up to 8 characters. 1) Create a new device using the "Create a new device" button and select "Connector'. Poiché la lunghezza dei meridiani è costante mentre la lunghezza dei paralleli varia con la latitudine, i rettangoli non hanno tutti le stesse dimensioni. Prévision propagation VHF- UHF Europe. World QRA Locator Grid Square Map Political; World QRA Locator Grid Square Map Political. Salons-Concours etc. From now on, the Leaflet API and free basemaps are used. 00 No tax. TK5EP's QRA locator (and more). Choose a new virtual port number, for example COM3. 281). 77. The main advantage is that the coordinates are expressed with very few characters and this is good for operating in CW. a. Zurück. You don't have to use a hi-res picture, it will be scaled to 600x600 pixels anyway. The circuit in test - with ARDUINO UNO. You must at first set your home location ! To do this, move the cursor to your home location, click on the map and a dialog box will open. Gear To get you started you don’t need to spend a lot of money on new gear. Need to find out a Maidenhead Locator quickly before going and operating somewhere. Geog is a suite of programs written by Andy Talbot. Export the locator map as an SVG or PDF, and then change the colors, opacity, etc. 281). XBS-TELECOM. nl Advertentie. K3NG's KEYER software is downloaded from the author's Gihub site and modfied/compiled with Arduino's IDE software. 00 European QRA Locator Map (V3) for Radioamateurs, ideal for the shack. Zum Beispiel könnte jemand in einem. This was the QRA-Locator system, devised in Germany, originally based on a two-stage sub-division of geographical longitudes and latitudes starting from the Greenwich meridian and from 40 degrees North. It has been developed for a course on Visual Basic as an example. The map contains data for the last 15 minutes. Sim card. Read the latest magazines about 5. Email: [email protected] by GoogleChrome. This was the QRA-Locator<br />. General information about South Africa where Rand/Germiston Airport is located in the city of Johannesburg. Maps. It will give you directions for your antenna (or beam headings as they're known) but it will also do something else for you. On-Line database of VHF & up QSO. IRLP Overlay For Google Earth; Echo Link Overlay For Google Earth; APRS Overlay For Google Earth; MMSSTV-decode by PC; MMTTY-RTTY decode by PC; EasyPal-digital SSTV decode by. You can change it using Ctrl-R. phone +44 (0) 1234 832700 Fax: +44 (0) 1234 831496New and updated data is shown on the map in real time without need to reload or refresh the page! Tracking data is stored in the database for six months. Find and browse HAM Radio WW Locator QTH. All bands and modes are count for the award. This page is a short description of the four phased verticals system i've build and used. Source: Site F5AIB. Amateur Radio Ham Radio Maidenhead Grid Locator in Google Maps. Don't be bothered by the Google warning window at startup,. DXCluster & RBN list; DXCluster map; RBN map; DXCluster azimuthal map; RBN azimuthal map; RBN graph; FT8 graph; Locators; The map contains data for the last 15 minutes. 77. For further information relating to the project please phone Council on 07 4761 5300 or email mail@charterstowers. Imp. Satellites, moon and space. More information on how to create your own application, use hi-res picture or include WRC in other applications will follow. 73, Codrut toggle quoted message Show quoted textWorld Meteorological Organization (WMO) squares is a system of geocodes that divides a world map with latitude-longitude gridlines into grid cells of 10° latitude by 10° longitude, each with a unique, 4-digit numeric identifier (refer chart at NODC World Ocean Database 2005 page). CONVERTOR by TK5EP (2014-2021) CONVERTOR written by Patrick EGLOFF TK5EP Move the mouse over the map and this page will show you latitude and longitude coordinates in WGS84 (both decimal and DMS), UTM as well as Maidenhead format. The QRA locator, also called QTH locator in some publications, is an obsolete geographic coordinate system used by amateur radio operators in Europe before the introduction of the Maidenhead Locator System. Our maps our printed in high definition on quality coated paper using pigmented inks which don't fade. Information about safe working near our pipes is. Great Circles & QRA Locator. Email: Login required to view Ham Member Lookups: 108657Rare countries The following countries had a single callsign that was received during the last seven days. It also allows to send DX-Spots and more features. K3NG Keyer; K3NG rotator Ethernet; K3NG rotator for HAM IV; K3NG rotator universal interface; Arduino and SIM800L;. Find your locator by exploring the map or by searching an address. Karten / Maps. We modify the following configuration files by leaving uncommented only the following lines. AG. I need to make a locator for UK addresses and I know Open Street Map has very good data for the UK, I was wondering how I can convert the data for house addresses, which is in xml form, into a locator in Arcmap. Re: QTH Locator maps. When the term 'grid square' is used, it can refer to a square with a side length of 10 km (6 mi), 1 km, 100 m (328 ft), 10 m or 1 m, depending on the precision of the coordinates provided. 2) The ground all around the antenna over a large number of wave length, typicaly > 2 for a quarter wave vertical. Once the HAAT value is obtained, it must be converted to feet (feet = m x 3. This letter denotes. 4 ± 0. Battery 3,[email protected]). 00. GridMapper - Grid and Station Locator - V. Queensland Fire and Emergency Services has an interactive map of Queensland on their website with information on current incidents and the level of warning in each location:. UV-998 LEIXEN. The IARU Locator (also known as the QTH Locator or Maidenhead Locator System) is based on a division of the globe, by latitude and longitude, into an 18 x 18 grid with origin (AA) at (90°S, 180°W). QTH Locator maps . Use this simple online utility to quickly find it by entering the National Grid Reference for your location and clicking "Calculate". - search by address, location. So far received 7 votes for a total score of 7. 76 = 52. GcmWin Great Circle Map. Quantitative Risk Assessment (QRA) is a method which allows for quantitative estimation of risk, given the parameters defining them. Salons-Concours etc. Réseau des Émetteurs Français. You can also use this service to find your QTH/QRA locator (or your grid square) by simply pointing at a location on the map. Interactive map with the position of amateur radio repeater bridges and more: Connect your PC to DMR,Yaesu Fusion, Dstar, M17, P25, NXDN. program to make Great Circle maps from any location. Argus d'avril 2020. PI1DAF, 2019-06-08 10:29:27, Almere FlevoLand NL. My scripts "WW locator map" and "Rain scatter" since offered a limited map with very few details. In our locator maps, that’s a click away. Or make a long click on the map at the place of interest. To keep it easy to manage, I'm listing mainly european sites. (604) 897-4616 604-897-4616 Greater Vancouver, Fraser Valley & Sea to Sky Vancouver IslandMap multiple locations, get transit/walking/driving directions, view live traffic conditions, plan trips, view satellite, aerial and street side imagery. Poiché la lunghezza dei meridiani è costante mentre la lunghezza dei paralleli varia con la latitudine, i rettangoli non hanno tutti le stesse dimensioni. It runs under the main versions of Windows. QRA locator map; Carte RS Europe; Circular SWR ruler; APRS; Arduino. You don't have to use a hi-res picture, it will be scaled to 600x600 pixels anyway. 7 Grid squares Magnetic equator Moon footprint ITU zones Search: Zoom/drag the map and click somewhere to calculate the grid square, extended locator, IOTA, DXCC, CQ&ITU zones, etc. Prévision propagation VHF- UHF Europe. Define Loss of Containment scenarios (LoCs) Assess the consequences (both effects and damage) for all LoCs. Antennas_manufacturers About Rtty mode Audio Recording Amplifiers Antennas Satellite Amateur Television ATV Aprs software Beacon Band Plan Ham Radio Capitals Europe DX cluster softwareThe Maidenhead Grid Locator system (also QTH) is a geographic co-ordinate system used by amateur radio operators to succinctly describe their location. Die Erdoberfläche wird dadurch in Felder unterteilt, die als Positionsangabe verwendet werden. Its purpose is to be concise, accurate and robust in the face. HB9RG, VHF Manager of USKA, showed the first prints of the Region 1 QRA-Locator map, issued on four sheets and made through his good. Great circles qra locator map. Victoria. PDF file can be enlarged and scaled to A3 and. Distributeur Matériel OM. The IARU Locator (also known as the QTH Locator or Maidenhead Locator System) is based on a division of the globe, by latitude and longitude, into an 18 x 18 grid with origin (AA) at (90°S, 180°W). For example, QRA locator map for VHF/UHF contest. All the principles stated here are of course valid for any other bands, but you can achieve the same game with. Imp. READ IMPORTANT NOTE BELOW. 20. or Longitude, you can look it up on QRZ. Without repetitions the system covered the area 0-52 degrees Eastern longitude and 40-66 degrees Northern latitude. RunwaysCONVERTOR by TK5EP (2014-2021) CONVERTOR written by Patrick EGLOFF TK5EP Move the mouse over the map and this page will show you latitude and longitude coordinates in WGS84 (both decimal and DMS), UTM as well as Maidenhead format. The Natural Area Code, or Universal Address, is a proprietary [1] geocode system for identifying an area anywhere on the Earth, or a volume of space anywhere around the Earth. Parking for Qra Arcoris is available in front of the shop at Jalan Kiara. The typical procedure to perform a QRA consists of the following steps: Identify relevant activities, units, and processes. HTF. QRA locator map - Rain Scatter map - et plus. com in a single category. It will now be necessary to run the software in administrator mode. This may be old news, but stumbled across this QRA Locator map today CONVERTOR by TK5EP (2014). HAM Wall Maps Special Offer. Data safety. com in a single category. Great Circles & QRA Locator. program to make Great Circle maps from any location. Summaries 144 MHz in Europe. New features have been added, such as: - search by QRA locator on 6 or 8. This was the QRA-Locator system, devised in Germany, originally based on a two-stage sub-division of geographical longitudes and latitudes starting from the Greenwich.