{
  "_note": "The net map in The network binder (binders.json \"map\": \"net\"). Plain text only: every string is escaped when rendered. geometry is the land file tools/build-maps.py writes (bump its ?v= when it changes: assets/ is cached for a day). Coordinates are decimal degrees, city/base level at most; lon is negative west. label is the short name drawn beside the dot; label_pos (n, s, e, w, ne, nw, se, sw; default e) says which side; label_gap (CSS px, optional) moves the label that much further from its dot on whichever side it lands (McClellan, 2026-10-13: its dot is all but on KPH's, and both names keep clear of both dots); the page tries that side first, moves a label that would overlap another label or dot to the first side that fits, and draws it only on tap, focus or Enter when none does (app.js netLabels). A transmit site with closed is kept for the record and not drawn. note (optional) is a sourced line shown in the site's panel when a reader hovers, taps or focuses it; leave it out rather than guess. precision says how exact the dot is: base, city, state or country. Our receivers are NOT listed here: the map reads them from stations.js (entries with lat and lon), the one receiver list.",
  "geometry": "assets/map/world-110m.json?v=1",
  "caption": "Known HFGCS stations, from public sources; not all current.",
  "sources": [
    {
      "for": "transmit_sites",
      "title": "The HF-GCS and Emergency Action Messages",
      "publisher": "Number Stations Research (the NSRIC HFGCS page)",
      "url": "https://www.numbers-stations.com/usa/hfgcs/",
      "accessed": "2026-09-24",
      "status": "Secondary source, not all current. The page gives no date. It lists the sites below as transmitting and Thule AB (Greenland) and \"Keflavik Global\" (Keflavik NAS, Iceland) as closed. Keflavik is in both lists; it is kept here marked closed and not drawn. \"MPA\" (location unknown on the page) is not drawn. The page's Air Force Eastern Test Range entry was removed from the map on 2026-09-29 (ruled): one search found no US Government source that lists Cape Canaveral, Patrick or the Eastern Range as an HFGCS station. Coordinates are the named base or town, placed by us, not given by the page."
    },
    {
      "for": "network_control",
      "title": "319th CS hosts High Frequency Global Communications System open house",
      "publisher": "U.S. Air Force, Grand Forks Air Force Base (Senior Airman Ashley Richards, 319th Reconnaissance Wing Public Affairs, 2 June 2023)",
      "url": "https://www.grandforks.af.mil/News/Display/Article/3415740/319th-cs-hosts-high-frequency-global-communications-system-open-house/",
      "accessed": "2026-09-28",
      "status": "Official Air Force page, read from the Internet Archive capture of 10 April 2026 (the site refuses scripted fetches). It shows HFGCS operations technicians of the 319th Communications Squadron at Grand Forks AFB, and HFGCS support provided there and at Joint Base Andrews. No Air Force fact sheet on HFGCS was found. The site list and the frequency are from the page above. The Grand Forks marker (added 2026-09-29) takes its 319th CS line from this page (HFGCS operations technicians of the 319th Communications Squadron work there) and its net control line from the Air Combat Command RFI below."
    },
    {
      "for": "puerto_rico_station",
      "title": "Request for Information: High Frequency Global Communication Systems (HFGCS) Puerto Rico Station (PRS) Recompete, with Attachment 1, the draft Performance Work Statement",
      "publisher": "U.S. Air Force, Air Combat Command, Acquisition Management and Integration Center (solicitation FA4890-24-R-0009), posted on SAM.gov 10 January 2024",
      "url": "https://sam.gov/opp/3fd0804391c44e2c850bf0aa6428e070/view",
      "accessed": "2026-09-28",
      "status": "Federal document. The RFI says: \"The Puerto Rico Station (PRS) consists of a transmitter, receiver/control site and antenna farms that are remotely controlled and operated 24 hours a day, 7 days a week by radio operators from two net control stations (NCS) located at Andrews AFB, MD and Grand Forks AFB, ND.\" (the Grand Forks marker's net control line). The draft PWS says the station \"consists of a transmitter, receiver/control site and antenna farms\" remotely operated from the net control stations at Andrews AFB and Grand Forks AFB; its sites are Isabela and Salinas; \"On Salinas, which is on Camp Santiago\"; its real property tables list Isabela as \"Comm, Tmtr\" and Salinas as \"Comm Rcvr\". So the Salinas site is the receiver site and the transmitter is at Isabela. No position inside Camp Santiago is given, and none is drawn."
    }
  ],
  "transmit_sites": [
    { "name": "Andersen AFB, Guam", "label": "Guam", "lat": 13.6, "lon": 144.9, "precision": "base", "label_pos": "e" },
    { "name": "Andrews AFB, Maryland", "label": "Andrews", "lat": 38.8, "lon": -76.9, "precision": "base", "label_pos": "e" },
    { "name": "Ascension Island", "label": "Ascension", "lat": -7.9, "lon": -14.4, "precision": "base", "label_pos": "e" },
    { "name": "Croughton, United Kingdom", "label": "Croughton", "lat": 52.0, "lon": -1.2, "precision": "base", "label_pos": "nw", "note": "The source's frequency list gives 6712 kHz for Croughton." },
    { "name": "Diego Garcia, Indian Ocean", "label": "Diego Garcia", "lat": -7.3, "lon": 72.4, "precision": "base", "label_pos": "e" },
    { "name": "Grand Forks AFB, North Dakota", "label": "Grand Forks", "lat": 48.0, "lon": -97.4, "precision": "base", "label_pos": "n", "note": "One of two HFGCS net control stations, with Andrews: radio operators here remotely control and operate the Puerto Rico Station (Air Combat Command, RFI FA4890-24-R-0009, SAM.gov, January 2024). HFGCS operations technicians of the 319th Communications Squadron work here (U.S. Air Force, Grand Forks AFB, 2 June 2023)." },
    { "name": "Elmendorf AFB, Alaska", "label": "Elmendorf", "lat": 61.3, "lon": -149.8, "precision": "base", "label_pos": "e" },
    { "name": "Hickam AFB, Hawaii", "label": "Hickam", "lat": 21.3, "lon": -158.0, "precision": "base", "label_pos": "e" },
    { "name": "Keflavik NAS, Iceland", "label": "Keflavik", "lat": 64.0, "lon": -22.6, "precision": "base", "label_pos": "w", "closed": true },
    { "name": "Lajes, Azores", "label": "Lajes", "lat": 38.8, "lon": -27.1, "precision": "base", "label_pos": "w" },
    { "name": "McClellan, California", "label": "McClellan", "lat": 38.7, "lon": -121.4, "precision": "base", "label_pos": "e", "label_gap": 4 },
    { "name": "Offutt AFB, Nebraska", "label": "Offutt", "lat": 41.1, "lon": -95.9, "precision": "base", "label_pos": "e" },
    { "name": "Salinas, Puerto Rico", "label": "Salinas", "lat": 18.0, "lon": -66.3, "precision": "city", "label_pos": "e", "note": "The HFGCS Puerto Rico Station's receiver site, on Camp Santiago; its transmitter is at Isabela (Air Combat Command, RFI FA4890-24-R-0009, draft PWS, SAM.gov, January 2024)." },
    { "name": "Sigonella, Sicily, Italy", "label": "Sigonella", "lat": 37.4, "lon": 14.9, "precision": "base", "label_pos": "s" },
    { "name": "Yokota AB, Japan", "label": "Yokota", "lat": 35.7, "lon": 139.3, "precision": "base", "label_pos": "e" }
  ]
}