[Towertalk] 80M vertical bandwidth question

RICHARD BOYD ke3q@msn.com
Thu, 16 Jan 2003 23:14:34 +0000


I'm working on an 80M vertical, fullsize, with two elevated radials.  The 
feedpoint is about 8' above the ground and the radials slope down slightly 
to 5' at the tie-offs.  I cut each of the wires for 70' to start with, to be 
able to prune.  It does, in fact, resonate below the band as I expected.  
I'm getting 290 kHz as the "low SWR" bandwidth -- that is, where the "hi 
SWR" indication does not come on on my FT-847 that I took portable running 
on a battery out to the base of the vertical.  I suppose that's 2:1 SWR 
bandwidth but I guess I'd have to check my FT-847 manual to see.

Two questions:

1.  What is the "high SWR" bandwidth of a radio like the FT-847?  2:1?
2.  Is 290 kHz SWR bandwidth typical?  I was kind of surprised it was that 
good.

73 - Rich, KE3Q



Rich Boyd


KE3Q/W3AO




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