Quote:
Originally Posted by Andrew2
Quote:
Originally Posted by rambo1152
The bit I have difficulty with is "The far end of the wire pointing towards the TX". Wouldn't that be a null point?
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If the wire was several wavelengths long, it would become more 'end fire' than 'broadside', a la Beverage (although without the end termination). I doubt most ordinary people would have room for it though! |
Yes, it would be operating as an end-fire antenna. The Moxon book has some polar diagrams, for antennas up to 2-lambda long and some longer; there's even acknowledgement that the directly end-on null is probably a lot less in practice than the equations would predict.
I've been looking around at places like
http://www.earlytelevision.org/ which has some good examples of pre-and post-WWII TV antennas, and looking at the 1930s records of amateur experimentatioin on the then-permitted 56/MC/s band; several operators in the famous Snowdon trials were using end-fed antennas but I haven't been able to fond evidence of my V Long-Wire.
[An incidental question: all the photos on earlytelevision.org show the US VHF antennas to be horizontally-polarised, but the UK ones are vertically-polarised. Why did the UK adopt vertical polarisation
]