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UK Broadcast Transmission |
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THE TRANSMISSION GALLERY
BARROW
| Photos by Martin Brown | Page last updated: 2021-11-30 |
| Band III DAB aerials have been added to the mobile phone tower at Barrow. BBC DAB entered service at Barrow on the 27th August 2015. These pictures were taken in the morning from a footpath that runs next to Mill Beck, a small river to the east of the site. A rather overgrown footpath that runs northeast of the site placed the masts with the sun directly behind. A site best photographed later in the afternoon. |
| Two tiers of band III dipoles for DAB radio at the top of the mobile phone tower. Ofcom data indicates that these aerials produce a cardioid pattern with maximum ERP to the east. |
| Top of the southern mast. |
| The centre of the wires strung between the two masts. I had expected to see two vertical wires attached here, but not in this instance. Clearly Barrow MF is not at T-aerial. Dave Porter writes: There's a note on the pics of Barrow MF re the connection via two wires from the mast top out to a section of two spaced wires on each mast to an insulated centre section. A doubt was expressed on the piece as to why are they there? The answer is that they are conversions to make the mast radiators effectively longer by the addition of top loading, turning each mast radiator into an inverted-L antenna. With the typical 45m masts freqs below 850 kHz are not adequately catered for as the masts are a bit short versus the wavelength. For Preston MF 855 kHz and the Notts site Trowell MF, this technique was used as well as power splitting and feeding different powers and phase to each mast to achieve directionality (normally a required null rather than an directional enhancement) The disadvantage with inverted-L operation is that unwanted skywave can be produced. |
| Top of the northern mast. |
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