You have the answer at the end of your e-mail. Multiple vertical
wires are good for broadbanding, but provide additional capacitance
to ground at a low height, thus reducing the effective height.
Broadbanding may have been important in an efficient commercial
station, but is unnecessary when ground resistances of 100+ohms make
the antenna broad enough.
Mike, G3XDV
==========.
> I remember seeing a multi top wire LF antenna with multi wire vertical
> conductors somewhere & I found it in the 'Low Frequency Experimenters
> Handbook' in an article written by Peter G3LDO. He shows a 4 wire top
> with a 4 wire vertical feed & describes it as a 'Traditional T LF
> Antenna'. What I am curious about is that if it is detremental to have
> this multi wire vertical arrangement as you stated, why has Peter
> shown it in his article? I have an Admiralty book 'Handbook of
> Wireless Telegraphy' (1938) which shows the same type of T antenna
> with a multi wire vertical section. I have also seen articles
> elsewhere (maybe on internet) regarding multi wire verticals & tops
> were the wires are in a circular arrangement/format & are presented
> as 'Cage Antennas & Cage Dipoles' although I believe to increase
> bandwidth.
>
> The reason I am interested is that I have thought about a similar
> arrangement because of my small garden area like Dick.
>
> Comments invited please.
>
> Gary - G4WGT.
>
>
>
> -----Original Message-----
> From: [email protected]
> [mailto:[email protected]]On Behalf Of Rik Strobbe
> Sent: 11 August 2006 22:10 To: [email protected] Subject:
> Re: LF: Re: antenna: how to get max. capacity
>
>
> Quoting captbrian <[email protected]>:
>
> > Make the vertical of three parallel conductors , each to the centre
> > of
> each
> > top wire
>
> Using multiple vertical wires will increase the antenna capacitance
> but also decrease the radiation resistance. I guess that a thing you
> don't want.
>
> 73, Rik ON7YD - OR7T
>
>
> Disclaimer: http://www.kuleuven.be/cwis/email_disclaimer.htm
>
>
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