We thought the Aliens had landed …

[Michael GilliganParticipant @michaelgilligan61133]

Driving from Matlock to Ashbourne this afternoon … We suddenly saw this:

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I’m very impressed !

MichaelG.

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Ref. https://atchistory.files.wordpress.com/2015/08/dvor-project.pdf

Edited By Michael Gilligan on 18/07/2021 20:05:51

[Michael GilliganParticipant @michaelgilligan61133]

[Speedy Builder5Participant @speedybuilder5]

Yep, that's a small one, Google "Chicksands radio Ariel"

[Robert Atkinson 2Participant @robertatkinson2]

It's a standard Dopper VOR (VHF Omnidirectional Range) aircraft navigation beacon. It transmits a radio signal with two 30Hz tones. The phase shift between them is the bearing from the station. The original (non Dopper) ones used a physically rotating antenna. Later ones had a rotating transformer and 4 fixed antennas. The doppler ones have lots of fixed antennas switched electronically.

Nomally located under the intersections of airways or near airports (terminal VOR).

Robert G8RPI.

[Michael GilliganParticipant @michaelgilligan61133]

Thanks for the detail, Robert …

I only posted because it was such a surprise to see it in a field, just beside a B Road

MichaelG.

[RobinParticipant @robin]

We have one of those up on Seaford head. It hums to itself and miraculously causes aircraft to turn 90 degrees as they pass overhead.

[OldMetallerParticipant @oldmetaller]

I've often driven past that and wondered what it was, thanks Michael!

John.

[old martParticipant @oldmart]

There's another one west of Gatwick airport in the village of Northchapel in West Sussex. The outgoing aircraft used to switch off their landing lights when passing over the beacon. I believe the morse code was MID, for Midhurst.

[Michael GilliganParticipant @michaelgilligan61133]

OldMetaller in particular may be interested to know that I have ‘rationalized’ the surprising location of the TRENT DVOR

It is very close to the Madge Hill triangulation point and is only three metres lower … and it has good vehicular access.

…All things considered; this seems a jolly good place to put a beacon.

MichaelG.

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[HacksawParticipant @hacksaw]

There's one in Buxted , East Sussex too , just off the A26 , in our horses old field ..

Edited By Hacksaw on 20/07/2021 13:01:13

[OldMetallerParticipant @oldmetaller]

Posted by Michael Gilligan on 20/07/2021 10:58:21:

OldMetaller in particular may be interested to know that I have ‘rationalized’ the surprising location of the TRENT DVOR

It is very close to the Madge Hill triangulation point and is only three metres lower … and it has good vehicular access.

…All things considered; this seems a jolly good place to put a beacon.

MichaelG.

.

I did wonder why they called it Trent, surely it's nearer to the mighty Derwent?!

John.

[Michael GilliganParticipant @michaelgilligan61133]

Posted by OldMetaller on 20/07/2021 21:48:06:

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I did wonder why they called it Trent, surely it's nearer to the mighty Derwent?!

John.

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Probably because of that big expanse of Carsington Water [owned by Severn Trent]

MichaelG.

[SillyOldDufferModerator @sillyoldduffer]

Posted by Michael Gilligan on 20/07/2021 21:57:35:

Posted by OldMetaller on 20/07/2021 21:48:06:

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I did wonder why they called it Trent, surely it's nearer to the mighty Derwent?!

John.

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Probably because of that big expanse of Carsington Water [owned by Severn Trent]

MichaelG.

Is it because it's callsign is TNT?

Sadly, this is another technology going the way of the misericord :

 

Been pondering why they're positioned where they are. Is it because they steer aircraft clear of airfields, or help steer them in? Turn left at TNT for Manchester. Biggles flew along railway lines while Algy took star sights and they never got lost!

Dave

PS Failed to think up a banging good joke about Trinitrotoluene…

Edited By SillyOldDuffer on 21/07/2021 16:58:31

[Michael GilliganParticipant @michaelgilligan61133]

Posted by SillyOldDuffer on 21/07/2021 16:57:03:

[…]

Is it because it's callsign is TNT?

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Vice Versa, I would think

MichaelG.

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… and I win a coconut 

http://www.pilotfriend.com/flightplanning/flight%20planning/beacon_decodes.htm

Edited By Michael Gilligan on 21/07/2021 17:26:40

[roy entwistleParticipant @royentwistle24699]

Could the fact that there is only one river Trent but several Rivers Derwent have anything to do with it ?

Or should that be River Derwents

Roy

Edited By roy entwistle on 21/07/2021 19:34:07

[roy entwistleParticipant @royentwistle24699]

double posting

Edited By roy entwistle on 21/07/2021 19:33:05

[SillyOldDufferModerator @sillyoldduffer]

Posted by Michael Gilligan on 21/07/2021 17:14:59:

Posted by SillyOldDuffer on 21/07/2021 16:57:03:

[…]

Is it because it's callsign is TNT?

.

Vice Versa, I would think

MichaelG.

.

… and I win a coconut

**LINK**

Edited By Michael Gilligan on 21/07/2021 17:26:40

I see your coconut and raise it with my pineapple. The real Trent is in Germany,

Dave

[MeunierParticipant @meunier]

Saw MichaelG's first picture and expected rotating/flashing multi-coloured lights to the sounds of ELO's 'Turn to Stone' rather than 'turn left to Manchester'
Suppose that dates me somewhat….
DaveD

[not done it yetParticipant @notdoneityet]

I thought that perhaps it was aliens and they had come to take him home.

[Robert Atkinson 2Participant @robertatkinson2]

Posted by SillyOldDuffer on 21/07/2021 16:57:03:

Posted by Michael Gilligan on 20/07/2021 21:57:35:

Posted by OldMetaller on 20/07/2021 21:48:06:

.

I did wonder why they called it Trent, surely it's nearer to the mighty Derwent?!

John.

.

Probably because of that big expanse of Carsington Water [owned by Severn Trent]

MichaelG.

Is it because it's callsign is TNT?

Sadly, this is another technology going the way of the misericord :

Been pondering why they're positioned where they are. Is it because they steer aircraft clear of airfields, or help steer them in? Turn left at TNT for Manchester. Biggles flew along railway lines while Algy took star sights and they never got lost!

Dave

PS Failed to think up a banging good joke about Trinitrotoluene…

Edited By SillyOldDuffer on 21/07/2021 16:58:31

The DVORs and DMEs are not being removed completely, just rationalised. NDBs (low frequency beacons that use a direction finding receiver on the aircraft are going.

VORs were placed at the junctions of airways and sometimes near airports if not already in covereage. This came from the use of the original VHF Radio Range that only had 4 "beams" that were aligned with the two airways. The O in VOR is ommidirectional, effectively an infinite number of "beams" giving 360 degree coverage.

Can't get rid of VOR and DME completely until there is a backup for GNSS.

Robert G8RPI.

[SillyOldDufferModerator @sillyoldduffer]

Posted by Robert Atkinson 2 on 22/07/2021 08:45:18:

Posted by SillyOldDuffer on 21/07/2021 16:57:03:

Posted by Michael Gilligan on 20/07/2021 21:57:35:

Posted by OldMetaller on 20/07/2021 21:48:06:.

…

…

…

Been pondering why they're positioned where they are…

Dave

…

…

The O in VOR is ommidirectional, effectively an infinite number of "beams" giving 360 degree coverage.

Robert G8RPI.

In which case they can be put almost anywhere convenient that provides adequate coverage. On an airfield, or a hilltop with a handy road as Michael suggested,

Clever stuff. Years ago I was impressed by the Lorenz blind landing system (later adapted into Knickebein and used to bomb Coventry) Lorenz used two overlapping beams, one transmitting Morse dashes, the other sending dots timed to fit into the gaps between dashes. A navigator flying along the beam hears strong dots if the plane veers to the right, and strong dashes if it veers to the left. (And this can be displayed visually for the pilot.) The dots and dashes merge into a balanced continuous tone when the centred on the beam. The clever bit was the inventor understanding that the tone is about 100 times more accurate than the dash and dot lobes.

Dave

[Andy CarruthersParticipant @andycarruthers33275]

Similar structures are (or were) found on RAF bases, an elevated ground plane with 18 cones – Digital Resolution Direction Finder (DRDF) used UHF receivers to phase compare signal and derive bearing which was fed to AR1 Mk5 displays producing a strobe line intersecting blip on the screen, I recall a variant also used VHF with different / co-located antenna

Those were the days… having left the RAF 30+ years ago was almost amused to hear my service described as "Cold War RAF" – I guess it was in hindsight

[Author]

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