I'm searching the formula for
a inverted V diple; the angle
is 60°.

I was wondering if at such
angle the bandwith decreases.

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What would you like calculate ?

What is your definition of 'bandwidth' ?

Are you concerned only with what the SWR meter is supposed to be measuring ?

Bandwidth depends as much on transmission line and matching arrangements, if
there are any, as on the V itself. Changing the apex angle is just as likely
to increase as to decrease bandwidth, depending on what it is before any
changes are made.

Download from following website in a few seconds program INV_VEE and run
immediately. It will estimate most characteristics of a 1/2-wave resonant
inverted-V, including input impedance of the dipole and of the input
impedance, R+jX, of the transmission line at the transmitter end.

BTW, although it may be possible to minimise SWR on the feedline by varying
apex angle, overall result may be a loss in efficiency. Relative to a
horizontal dipole the V has a lower radiation resistance and a higher ground
loss resistance. The effects interact with each other. The program
demonstrates. All dimensions and angle can be varied "What-if ? "
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Regards from Reg, G4FGQ
For Free Radio Design Software
go to http://www.g4fgq.com
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