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Hermes Aerial Set

Technical Information

Catalogue No: C0350
Category: Surveillance/Acoustics
Object Type: Sensor/Transducer
Object Name: Hermes Aerial Set
Part No: ?
Serial No: ?
Manufacturer: GEC Avionics
Division: Unknown
Year of Manufacture: Unknown
Dimensions: Width (mm): 500
Height (mm): 780
Depth (mm): 430
Weight (g): 136
Location: Rack RAA06 [Main Store]

[on tetrapod aerial sleeve] 2225
[on whip aerial sleeve] 2122


These three aerials are for the Hermes system; a fourth whip-aerial type is missing.

The given dimensions are for the largest type (the folded tetrapod aerial with the hook) opened out, so the four arms point to the corners of a tetrahedron. This aerial is used with the range-extending Relay Unit and can be hung from a tree branch to maximise range.

The thin whip aerial is 480mm long and its base is 23mm diameter, weighing 40g.

The short helical aerial is 185mm long, and 15mm x 48mm at its base, weighing 65g.

All aerials use TNC connectors (TNC = Threaded Neill–Concelman, named after its two designers; BNC is the bayonet version).

Hermes is a family of VHF radio linked equipment using both seismic and passive infra-red sensors to detect vehicles and men, giving clear indication of classification, direction and numbers. The hand held monitor can simultaneously display the information from a group of up to 10 sensors and can respond to up to 80 sensors in groups of ten. Relay units are provided to enhance the range between sensor and monitor. The equipment was made at Borehamwood (Manufacturer's code: K0978) but was maintained by the Aviation Service and Repair Division at Rochester.

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