RE: LF: EA in LF soon

[VIGILANT Luis Fernández <luis@vigilant.es>]

Hi Stefan

 

Unfortunately, even with bucket facing sky ..... rain will not be a problem here !

Hardly 95 litres per square meter collected since january 1st. And only thanks to rain during last week

 

I prefer to set it appart. It is a truncated cone, so would have a natural tendence to "unwind" just by gravity

In the hot summer I would surely find the cable messed down at the base of the pipe :-)

 

73 from the tree!
Enjoy :-)

 

73 de Luis

EA5DOM

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De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de DK7FC
Enviado el: lunes, 11 de abril de 2016 18:25
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: EA in LF soon

Hi Luis,

Turning the bucket will solve your problem. Its like a variometer where you can add or substract L by turning the coil.
But don't collect to much water in the bucket ;-)

73 from the tree!
I forgot to take my netbook up here so now i cannot program the GPS module :-/ :-)

Am 11.04.2016 16:48, schrieb VIGILANT Luis Fernández:

Hi Dave, Stefan, LF ! :-)

 

Well, the big coil (double layer) is wound in the right sense, as CCW. Just as the other coils

But unfortunately it is wound top to bottom, and the coils in the pipe are wound bottom to top

Reversing the plastic bucket I would place both coil winds bottom to top but in opposite senses (inner CCW outer CW)

which I'm afraid would not work either. Right ?

 

Effectively this makes the fields to cancel when you get one into the other. Already tested !   :(

 

Taking the last coil appart will be probably the best option. Can rewind the second coil, which would be the easier way to get

both coils coupled, but Q will reduce with coupled coils and seems I do not need so much inductance to reach LF

 

73 de Luis

EA5DOM

 

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De: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org] En nombre de DAVE PICK
Enviado el: lunes, 11 de abril de 2016 15:24
Para: rsgb_lf_group
Asunto: Re: LF: EA in LF soon

Luis

Good job!

But if the top coil is wound the wrong way it will be subracting from the main coil.

Move it away from it, maybe stand it on something else a metre away, this will reduce the mutual coupling and increase the total inductance.

If it had been would the same way, as Stefan said, moving it closer would increase the inductance - but as it is the wrong way it decreases!

73

Dave G3YXM

On 11 April 2016 at 10:05 VIGILANT Luis Fernández <luis@vigilant.es> wrote:

Hi LF

 

My progress to get access to LF:

 

Added a coil on top of the 300mm pipe. With this in series can reach resonance at 270KHz

https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/IMG_20160409_183709.jpg

https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/sark_029.bmp

 

Then added another coil. Two layers winding, reaching 152KHz

https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/IMG_20160411_093327.jpg

https://dl.dropboxusercontent.com/u/7162072/Fotos%20varias/MF/sark_031.bmp

 

I'm afraid I winded "the wrong way" to get it working as yougurt cup over the top coil. Will try to

reverse it. Anyway a convenient fixing (not the one shown in picture) can be made keeping one over the other

 

Next is to play with top load capacitive wires to increase capacity and get it down to 137KHz

 

.....keep tuned ! ;-)

 

73 de Luis

EA5DOM