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Old July 19th 03, 10:33 AM
Ian White, G3SEK
 
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Steve wrote:
The only question I have now is probably a daft one but here
goes....... the plans for this antenna specify that the reflector
should be at position 0 on the boom and D13 should be at 8300mm
relative to the position of the reflector.. Where would one drill the
hole for the reflector ? i.e how far in from the end of the tube, and
how far past the hole for the last director would the boom actually end ?


If the hole is far enough from the end that it doesn't weaken the
element mounting mechanically, that also seems to be OK as regards the
electrical effect of the metal boom.

It's nice to use plastic end caps (most yagi manufacturers will sell you
a few) so the practical distance for the holes is just far enough so
that the end cap will push in without fouling anything inside.

Or make it about pi/2 times the width of your thumb, and then trim the
end cap until it fits... no worries.


--
73 from Ian G3SEK 'In Practice' columnist for RadCom (RSGB)
Editor, 'The VHF/UHF DX Book'
http://www.ifwtech.co.uk/g3sek