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Old 6th Dec 2014, 3:39 pm   #220
SteveCG
Nonode
 
Join Date: Jun 2009
Location: Herefordshire, UK.
Posts: 2,495
Default Re: 405-Line VHF Aerials in 2013-2014

Valve'n'vinyl

May I suggest that you cut down the existing elements for your Band II aerial. Antiference elements were made out of good material - nothing a clean up with a Brillo pad would not fix for appearances either.

Three points for you:

1) The aerial is a director-dipole design, with the dipole being the rear pair. So remember that the highest frequency is determined by the length of the director (front pair).

2) The design is nearly omnidirectional at the bottom end of the frequency channel. So in its 405 line use the sound signal was picked up from all around. There was directivity though at the higher - vision - end of the channel.

3) Radio amateurs use 50 Mc/s these days. So you could attempt to re-commission the aerial to its full size glory and use it if you were so interested... Although I do see that a couple of the elements are broken near the junction box.
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