Ron,
that's right. It would be best to limit the phasing line lengths to 270 rather
than 450 degrees. With changes in frequency the phase error will change faster
with a longer line. If no balun or other reversal is performed things will
still work except the antennas will fire 180 degrees opposite relative to a 90
degree line?
Dave WX7G
----- Original Message -----
From: George & Marijke Guerin<mailto:gmguerin@voyager.net>
To: DAVID CUTHBERT<mailto:DAVIDNNAN@MSN.COM> ;
topband@contesting.com<mailto:topband@contesting.com>
Sent: Tuesday, December 14, 2004 6:11 AM
Subject: Re: Topband: 4-square phasing
See comment below on phasing reversal with a BalUn or UnUn:
----- Original Message -----
From: "DAVID CUTHBERT" <DAVIDNNAN@MSN.COM<mailto:DAVIDNNAN@MSN.COM>>
To: <topband@contesting.com<mailto:topband@contesting.com>>
Sent: Monday, December 13, 2004 11:28 PM
Subject: Topband: 4-square phasing
> Ron,
>
> if I have it figured correctly the 3/4 wavelength lines will cause the two
> extra elements to lag by 180 degrees. You can fix this by doing one of
> these:
>
> 1) adding 180 degrees of line to the two existing element feedlines
> 2) adding 180 degrees of line to the two 270 deg lines to have 450 deg
> lines
> 3) invert the phase of the two 270 deg lines with a choke balun (hot to
> shield/shield to hot)
A regular balun or UnUn will also do the 180 degree reversal job:
Top of first winding to 270 deg line center conductor, bottom to shield.
Top of second winding to shield, bottom of second winding is reversed phase
coax center conductor connection.
The transformer can go on either end of the line!
George K8GG
> Dave WX7G
... snip...
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