ARLA/CLUSTER: Christmas Lights ou como fazer da sua antena uma Arvore de Natal

[João Gonçalves Costa]

Here is a novelty way to use up old sets of Christmas lights - as a HF vertical antenna !

The site has an animated picture.
http://g8jnj.webs.com/

This animation shows changes in current distribution along a 5m tall base fed vertical, consisting of a string of Christmas lights with approx. 40 bulbs connected as four parallel strings of ten and fed with an auto tuner at the base.

The frequency in use increases gradually from 7MHz (most current at base) up to 50MHz (two current peaks with a null in the middle).
The lights are brighter where the antenna current is greater.

Note that the lamps have a non-linear response, as their resistance changes as they heat up. So the current distribution shown by the lights is not quite correct, but it does provide a good indication.

Martin G8JNJ
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