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 | 52║ 49.59' N 001║ 11.40' W |
| Rated Range | 20 Nautical Miles |
| Keying | A2A |
| Modulation Frequency | 400 Hz |
| CW Ident | EME |
| Keying Speed | 7 wpm |
| Transmitter | Southern Avionics SA-100 100W cw / 400W PEP |
| Antenna | Jaybeam ISS-12 12-metre tower |
| Earth system | 36-off 15-metre radials |
| Frequency | 393.000 kHz (actual freq is 393.015 kHz) |
| Location | 52║ 49.43' N 001║ 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 |
EME has recently been refurbished and uses a Southern Avionics SA-100 dual transmitter. EMW uses the dual-transmitter ABX400 which is fully solid-state and was 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! An
noticeable effect of this is a phenomena known as "sideband imbalance" regularly
reported by the beacon monitors at Pailton.
A trial off-air monitoring system has been in use since mid-2001 comprising of Fernau MR-110 monitor receivers and Wellbrook ALA-1530 active loop antennas.
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 Calibration Facility, 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 24 June 2004 16:25
⌐ Nick Button 2004
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.