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Re: LF: 472kHz TX without an antenna: it gets better (701km with around

To: <[email protected]>
Subject: Re: LF: 472kHz TX without an antenna: it gets better (701km with around 5mW ERP)
From: "Graham" <[email protected]>
Date: Sun, 6 Jan 2013 18:10:43 -0000
Importance: Normal
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That's a  good  start  then Roger,  !
 
I  think it  could be visualised  as a    gradual  / gradient  , so the   top  wires  have the  max  current  in free  space  and the  return  path is  some  form of  diffused  large  cross  sectional  area     , you  could  model  it  on 2  meters  ..using  what  for  the  ground ... cardboard box , bin bag , water  and jar of cooking  salt , add  to  increase  conduction   ?
 
Could  be  simply  gain is from the  increased  amps  in the  top  radiator , so  the  model  would  be  quite  small  for 2  mtrs , kitchen  table  job !
 
.G..
Sent: Sunday, January 06, 2013 5:53 PM
Subject: Re: LF: 472kHz TX without an antenna: it gets better (701km with around 5mW ERP)

Well this is just about the only explanation that will make any sense Graham.

If so, I would expect some directivity and when I analyse the results after an overnight run we'll see if stations off the side of the "loop" are statistically weaker (compared with the Marconi vertical) than stations in the line of the "loop". If so, this would tend to support loop like operation. The DL-SWL and PA reports are roughly in the plane of the wire, but there are plenty of reports from other directions too.

Of course, here in the UK we have highly saturated ground - I have NEVER known East Anglia to be so waterlogged - so the effective loop area cannot be that great.

Anyone care to offer other suggested modes for this "non antenna"?

73s
Roger G3XBM





On 6 January 2013 17:42, Graham <[email protected]> wrote:
R,
 
I thought  it  was  established  that  the  ground  did  not  'exist'  for  some  20/40  feet  or more from the  surface  and  as  such, your  using a  loop  with the  bottom  wire   40  feet  lower than the  top  wire ?
 
This was the  principal  of  ground lying   Ae  .would  not  work  on  salt marshes  , but  for  normal  ground , lossey but  capable  of  supporting  radiation ?
 
G..

Sent: Sunday, January 06, 2013 5:28 PM
Subject: LF: 472kHz TX without an antenna: it gets better (701km with around 5mW ERP)

OK, now I am totally amazed....

Just got a WSPR spot from DL-SWL in Germany (JO52hp) at 701km using just the earth electrode system on TX. Please someone, explain why this works as well as it does, especially considering my ERP must be around 5mW at best.

Incidentally G3XIZ is a colossal +7dB S/N on WSPR and I think Chris would be easily workable on CW using the earth electrode system.

73s
Roger G3XBM



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