THE TRANSMISSION GALLERY
TALES FROM A COLD FIELD
Being fairy-stories told to the author as a young engineer
© Ray Cooper, 2005 (2nd revised edition, Jan 2006)
|Appendix C: The Reserve TV Mast
This 150ft. mast was of lattice construction, square cross-section (unlike the main mast, which was triangular in cross-section) and so had four lanes of stays. It was originally built to support a reserve Band I TV aerial array, to be used if extensive work on the main aerials or combiner became necessary. This array could not handle the same power, nor did it have anything like the service area coverage, of the main array.
When the top of the main mast had to be rebuilt to accommodate the new UHF aerials in 1964, it was deemed that the reserve aerial was not suitable to maintain the service for the extended period of the mast rebuild, and so a new set of reserve aerials were installed on the main mast, at about the 500ft. mark. This left the 150ft. mast empty, but not for long: in order to get BBC2 on-air as soon as possible, before the main mast works were complete in fact, a set of UHF aerial panels were installed on the old 150ft mast, which, fed at lower power, gave a service of sorts to Birmingham and other favoured areas.
y the time that BBC1 and ITV went onto UHF in 1969, the short mast was in the way of the new IBA building, and had to be felled. This was done by the simple expedient of applying an oxy-acetylene torch to the bottom of one of the mast stays. The mast came down quite gracefully and with full regard for tradition, bending sharply at the one-third-of-the-way-up point where most masts seem to give when felled in this manner.
Appendix D >