Re: Fwd: Re: LF: VK1OD's analysis of the MiniWhip antenna

[pat <g4gvw@aol.com>]

Hi Jay,

That still leaves us with the anomaly that in the context we are discussing here viz. 'LF', the "spacecraft" might be an awfully small piece of real estate compared to the wavelengths we are dealing with :>)
It's the proverbial "isotropic" source problem isn't it?

73


On 10/07/13 13:04, jrusgrove@comcast.net wrote:

Pat

 

Don't believe they are 'loading up' the spacecraft itself against the universe ;~). Antennas take the form of monopoles (spacecraft is the 'groundplane'), dipoles, quad helix etc.

 

Jay W1VD  WD2XNS  WE2XGR/2 

----- Original Message -----

From: pat

To: rsgb_lf_group@blacksheep.org

Cc: edgar

Sent: Wednesday, July 10, 2013 5:51 AM

Subject: Re: Fwd: Re: LF: VK1OD's analysis of the MiniWhip antenna

I don't know if my previous posts arrived but I still prefer to think that a "small" antenna is one plate of a capacitor and the rest of the universe is the other. This then enables the spacecraft antenna to work. The universe is not a great big empty space!

73 de Pat



On 10/07/13 08:58, edgar wrote:

I sent this message two days ago and I did not see it arrive.

Although the subject is now out of context, I would like some comment on my question.

Regards, Edgar
Moonah, Tasmania.


-------- Original Message --------

Subject:	Re: LF: VK1OD's analysis of the MiniWhip antenna
Date:	Mon, 08 Jul 2013 00:06:50 +1000
From:	edgar <edgarjtwining@virginbroadband.com.au>
To:	rsgb_lf_group@blacksheep.org

Hi Pieter-Tjerk,

If that is the case, and all the parts are at the same potential, how 
does a space craft, radio controlled model aeroplane

get their signals?

Surely every conductor in the unit will have a difference in potential 
due to being in a electromagnetic field.

Even in the legs of the FET. Although the potential will be extremely small.

Surely it is only necessary to have a change of the Vgs voltage of the FET.

So the geometry of the antenna has to be made to allow this to occur.

Regards, Edgar
Moonah, Tasmania.

-- 
73 de pat g4gvw
es gd dx
qth nr Felixstowe
East Coast UK

-- 
73 de pat g4gvw
es gd dx
qth nr Felixstowe
East Coast UK