Difference between revisions of "Talk:Installing a TV aerial"

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Perhaps a simpler statement would be in order?  
 
Perhaps a simpler statement would be in order?  
 
--[[User:John Rumm|John Rumm]] 00:24, 5 March 2009 (GMT)
 
--[[User:John Rumm|John Rumm]] 00:24, 5 March 2009 (GMT)
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Note I have added an aerial quality assessment "bullet list" to the CAI section mentioning baluns now. I also took out the gain categories bit since this is duplicated in the gain section anyway.
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--[[User:John Rumm|John Rumm]] 01:05, 5 March 2009 (GMT)

Revision as of 01:05, 5 March 2009

Baluns

why would one delete this:

Baluns

- Nearly all TV aerials are described by the manufacturer as 75 ohm aerials, yet nearly all are really designed as 300 ohm aerials, with construction details reducing this to some degree, but not to 75 ohm. Connecting a 300 ohm aerial to 75? cable causes loss of gain, tendency to reflections, and some degree of degradation of signal quality. - - Better aerials have a small balun inside that transforms the 300 ohm signal to a genuine 75 ohm feed. All CAI approved aerials have this. NT 23:55, 4 March 2009 (GMT)


It did not really seem that relevant since the article already strongly suggests CAI aerials (which will all have a balun when required (i.e. allowing for CAI approved Log periodic aerials which are naturally balanced and have a 75 ohm impedance)). It was also somewhat inaccurate as currently described (see Bill's comments about the effects of parasitic elements on characteristic impedance).

Perhaps a simpler statement would be in order? --John Rumm 00:24, 5 March 2009 (GMT)

Note I have added an aerial quality assessment "bullet list" to the CAI section mentioning baluns now. I also took out the gain categories bit since this is duplicated in the gain section anyway. --John Rumm 01:05, 5 March 2009 (GMT)