The following list contains the aeronautical radio beacons that were active in Denmark in the mid of the 1950s. All information is outdated and may not be used for navigational purposes.
At this time there were mainly non-directional beacons (NDB). The identification of most en-route beacons consisted of three letters and began with an O. Other radio beacons, especially those for the approach to airfields, had two letters, mostly according to the name of the airfield.
Copenhagen Kastrup airport was equipped with the Instrument Landing System (ILS).
Radio beacons and airways

Northern parts of Jutland, Funen, Zealand (Source: DoD)

Zealand with Copenhagen (bottom left) (Source: DoD)

Southern parts of Jutland and Funen (Source: DoD)

Funen, Zealand, Lolland, Falster, Bornholm (top) (Source: DoD)
Explanations

Abbreviations
approx. | approximately | |
civ | civil | civil operator |
GP | Glide path | Glide path transmitter |
ILS | Instrument Landing System | (Approach and landing aid) |
IM | Inner Marker | Marker beacon just in front the runway |
kHz | Kilohertz | (Unit for frequency) |
L | Locator | Non-directional beacon for the approach |
LLZ | Localizer | Localizer transmitter |
LMM | Locator Middle Marker | Combination of Middle Marker and Locator |
LOM | Locator Outer Marker | Combination of Outer Marker and Locator |
m | Meter | (Unit for length) |
MHz | Megahertz | (Unit for frequency) |
mil | military | military operator |
MM | Middle Marker | Marker beacon |
NDB | Non-directional beacon | Non-directional beacon on long or medium waves |
NM | Nautical Miles | (Unit for length) |
OM | Outer Marker | Marker beacon |
PRMG | ПРМГ Посадочная радиомаячная группа | Soviet / russian military instrument landing system |
RSBN | РСБН Rадиотехническая система ближней навигации | Soviet / russian military radio navigation system |
SBA | Standard Beam Approach | Approach system, Lorenz system, predecessor of the ILS |
THR | Threshold | Runway threshold (most often with number of runway) |
transf. | transformed | Coordinates were converted from a different reference system, therefore there may be deviations. |
VAR | Visual-Aural Rnange | |
VOR | VHF Omnidirectional Radio Range | |
W | Watt | (Unit for power) |
WGS84 | World Geodetic System 1984 | (geospatial reference system, GPS coordinates) |
Directory
For historical information only, do not use for navigation or aviation purposes!
Aalborg: Air Base (Flyvestation Aalborg, Aalborg Lufthavn)
Runway 27:
Aalborg: ILS 27
Channel Y. To runway 27 (269°).
Aalborg: NDBN5706 E00955 (approx.), 268°/1.4 NM to field
Google MapsOZJ, 325 kHz
Located about 2 km east of the main runway.
Aalborg: MM 27
Dot Dash, 75 MHz
Aalborg: IM 27
Dots, 75 MHz
Tirstrup: Air Base (Flughafen Aarhus, Tirstrup Lufthavn)
Aarhus: NDBN5618 E01041 (approx.), 284°/1.6 NM to field
Google MapsOZD, 394 kHz
Als: NDBN5452 E00954 (approx.)
Google MapsAL, 323 kHz
(Kegnæs)
Anholt: NDBN5643 E01131 (approx.)
Google MapsAT, 398 kHz
Operated on 30 minutes request.
Billum: NDBN5537 E00819 (approx.)
Google MapsOZR, 355 kHz
On airway Amber Seven (A7).
Dalgas: MarkerN5622 E00827 (approx.)
Google Maps75 MHz
On airway Amber Seven (A7).
For historical information only, do not use for navigation or aviation purposes!
Hanstholm: NDBN5707 E00836 (approx.)
Google MapsOWM, 361.5 kHz
At the intersection of airways Amber Seven (A7) and Red Four (R4).
Jernen: NDBN5524 E01219 (approx.), 043°/16.9 to Copenhagen Katrup
Google MapsJN, 369 kHz
On airway Amber Nine (A9).
Copenhagen: Kastrup Airport (Københavns Lufthavn)
København: Saltholm Flak LocatorN5542 E01244 (approx.), 209°/5.4 NM to field
Google MapsSF, 391 kHz
At Saltholm Flak island.
Runway 04:
København: NDBN5534 E01235 (approx.), 044°/4.0 NM to field
Google MapsOXS, 383 kHz
København: RangeN5535 E01237 (approx.), 044°/1.2 NM to field
Google MapsCH, 267.5 kHz
The four predefined courses to the Range were: 044°, 134°, 224° and 314°.
Runway 12:
København: Amager LocatorN5540 E01226 (approx.), 115°/8.54 NM to field
Google MapsBL, 320 kHz
Previous ident: NW.
København: ILS 12
OXS2, 109.9 MHz
København: OM 12
125°/3.85 NM to THR 12
Dashes, 75 MHz
København: LMM 12N5538 E01237 (approx.), 125°/1.08 NM to THR 12
Google MapsLocator: L, 398 kHz
Middle Marker: Dot Dash, 75 MHz
København: IM 13
125°/0.32 NM to THR 12
Dots, 75 MHz
Runway 22:
København: ILS 22
OXS, 109.1 MHz
København: LMM 22N5538 E01241 (approx.), 227°/1.18 NM to THR 22
Google MapsLocator: K, 398 kHz
Middle Marker: Dot Dash, 75 MHz
At Nordre Røse.
København: IM 22
227°/0.04 NM to THR 22
Dots, 75 MHz

Copenhagen Kastrup Airport with radio beacons in 1951 - The range with its four predefined courses was located southwest of the field. (Source: DoD)
Mygenaes: NDBN6206 W00740 (approx.)
Google MapsMY, 291.9 kHz
Mykineshólmur, Faroe Islands (Færøerne/Føroyar). Operated in clear weather H+00, in fog H+00 and every 6 minutes.
Narsarsuaq: Airport (Narsarssuak Air Base)
Narsarssuak: NDBN611010 W0452545 (WGS84, transf.)
Google MapsBW, 279 kHz
Greenland (Grønland). The location of the beacon was indicated as on the other side of the water in the north of the airfield - I wonder if this is correct.
Nolsa: NDBN6157 W00636 (approx.)
Google MapsNO, 291.9 kHz
Nólsoy (Nolsø), Faroe Islands (Færøerne/Føroyar). Operated in clear weather H+02, 08, in fog H+02 and every 6 minutes.
Odense: Airport (Odense Lufthavn, Beldringe Lufthavn)
Odense Beldringe: NDBN5528 E01020 (approx.)
Google MapsOD, 349 kHz
For historical information only, do not use for navigation or aviation purposes!
Parnas: MarkerN5527 E01136 (approx.)
Google Maps75 MHz
On airway Red One (R1).
Præstø: Presto MarkerN5509 E01159 (approx.)
Google Maps75 MHz
On airway Amber Nine (A9) between Jernen and Rødbyhavn.
Rødbyhavn: NDBN5439 E01121 (approx.)
Google MapsRY, 328 kHz
On airway Amber Nine (A9) between Presto and Michaelsdorf.
Rønne: Airport (Bornholms Lufthavn, Roenne)
Rønne: NDBN5503 E01448 (approx.), 294°/1.6 NM to field
Google MapsOZO, 325 kHz
Operated from 0330 to 0900 and from 1500 to 1900.
Roskilde: NDBN5536 E01205 (approx.)
Google MapsRO, 316 kHz
Simiutaq: NDB
090°/44.9 NM to Narsarssuak Air Base
SI, 359 kHz
Simiutaq: Racon (USAF)
N6041 W04631 (approx.)
Google Maps2-1-1-2, 9310 MHz
Operated continuously.
Greenland (Grønland)
Kangerlussuaq: Airport (Søndre Strømfjord, Søndrestrom Air Base)
Søndrestrom: Racon (USAF)
N6701 W05041 (approx.)
Google Maps2-2-1-1, 9310 MHz
Located at field. Limited to 40 miles in north and south quadrants due to adverse terrain conditions.
Greenland (Grønland)
For historical information only, do not use for navigation or aviation purposes!
Thule: Air Base
Thule: NDBN763229 W0684806 (WGS84, transf.)
Google MapsTL, 321 kHz
Greenland (Grønland)
Thule: Racon (USAF)
N7631 W06842 (approx.), 070°/0.7 NM to field
Google Maps1-2-1-1, 9310 MHz
Operated continuously. Caution: Mast 1,797 feet ASL located approximately 4 miles northeast of beacon.
Greenland (Grønland)
For historical information only, do not use for navigation or aviation purposes!
Maps

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