You are drawing a conclusion without knowing all the information needed. The
disk on the antenna acts like a capacitor to the rest of the antenna.
Read a little on how an antenna works. It depends upon the capacitance
between ends for return current.
Placing the disk in line only looks like a fatter element at that point
which means more capacitance.
73
Gary k4FMX
> -----Original Message-----
> From: amps-bounces@contesting.com [mailto:amps-bounces@contesting.com]
> On Behalf Of pc5m, Carel
> Sent: Sunday, March 21, 2010 1:03 PM
> To: amps@contesting.com
> Subject: Re: [Amps] placement of RF choke bypass cap.
>
> Bill,
>
> You are right !
>
> Changed my setup and to summarize the results:
>
> #1. With the disk, Fres = 480 MHz
> #2. With disk connected parallel to horizontal wire (see
> www.pc5m.com/skineffect2.jpg ). Fres = 260 MHz
> #3. With disk connected in between (no through wire at all) ( see
> www.pc5m.com/skineffect1.jpg) . Fres = 260 MHz
>
> I suppose I can only conclude that the RF current will/must go through
> the
> disk and not follow the long path (due to alleged skineffect) around the
> disk.
>
> Again a myth busted ?
>
> Gl, Carel.
> ---------------------------------------------
>
> ORIGINAL MESSAGE:
> >
> >Try this: Measure the spacing from the bottom edge of the disk to the
> >ground plane, then re-solder the disk at the edge of the disk,
> >maintaining the same spacing. Now the disk is acting as just a
> >capacitor, without having the wire's RF flowing through it.
> >
> >73, Bill W6WRT
>
>
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