East Midlands Airport operates two LF NDB's. They are both used as "Locator" beacons to aid aircraft making instrument approaches to runways 09 and 27. Both are located approximately 4 Nautical Miles from the threshold of either runway on the extended centreline.
The NDB's are set up to give a field strength of 70uVm-2 (microvolts per square metre) at their rated range, 20 Nautical Miles for EME and 10 Nautical miles for EMW.
| Frequency | 353.500 kHz |
| Location | 52º 49.59' N 001º 11.40' W |
| Rated Range | 20 Nautical Miles |
| Keying | A2A |
| Modulation Frequency | 400 Hz |
| CW Ident | EME |
| Keying Speed | 7 wpm |
| Transmitter | IAL ABX-400 rated at 100W cw / 400W PEP |
| Antenna | Jaybeam ISF-12 12-metre fibreglass whip |
| Earth system | 36-off 15-metre radials |
| Frequency | 393.000 kHz (actual freq is 393.015 kHz) |
| Location | 52º 49.43' N 001º 27.16' W |
| Rated Range | 10 Nautical Miles |
| Keying | A2A |
| Modulation Frequency | 400 Hz |
| CW Ident | EMW |
| Keying Speed | 7 wpm |
| Transmitter | IAL ABX-400 rated at 100W cw / 400W PEP |
| Antenna | Jaybeam ISF-12 12-metre fibreglass whip |
| Earth system | 36-off 15-metre radials |
Both beacons use the dual-transmitter ABX400's which are fully solid-state and were originally manufactured by IAL. The transmitters also include a fully automatic ATU for base-loading of the Jaybeam vertical antenna and a fault monitoring system which will change over transmitter or shut the system down in the event of a fault. Full remote control and monitoring is available to the Engineers at the airport via a land-line telemetry system.
The antennas are very inefficient at this frequency and the base capacitance of the ISF-12 is in the order of 140 pF. The resultant high Q of this system means that the tuning is very critical hence the need for the automatic ATU!
The beacons are maintained by the Air Traffic Engineers of the airport's Airfield Engineering department. Scheduled on-site maintenence is performed on a quarterly basis with weekly measurements being carried out by the Civil Aviation Authority's Radio Measuring Station, located at Pailton in Warwickshire.
Weekly measurements by the CAA check the following parameters:
EMW is actually operated 15 Hz high of its nominal frequency to allow remote measurements to be carried out by the CAA, due to co-channel interference from another beacon using the same frequency.
No QSL cards exist as such but any reception reports may be directed
to:
Nick Button, Air Traffic Engineer.
Airfield Engineering,
East Midlands Airport Ltd.
Castle Donington
Derby.
DE74 2SA.
Reception reports should be accompanied by a stamped self-addressed envelope for a speedy reply.
Go to EAST MIDLANDS AIRPORT Official web site
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Last Updated 02 Feb 2000 07:25
© East Midlands Airport (Airfield Engineering) 1999
This information is intended purely as an information source for radio listeners and should not be used for air navigation purposes. Fliers should always consult the UK AIP or similar approved documents.