Sunny Day Musings...

[Vipersan]

Hi friends ..
Currently sat in the shade of my 1.8pf ...enjoying the indian summer ;)
Gawd knows we deserved it ..

Idle musings caused me to think about the practicalities of receiving both Linear and Circular polarities on on lnbf 'lump' at the focus of the 1.8 ..
It occurred to me that this item doesn't exist ..
Next question is ....why?
Here is a much simplified drawing of what my musings led to ..
effectively 2 complete c band lnbs joined in series with a dielectric prate seperating the 2 halves ..the rear lnb responsible for circular depolarization ...the front lnb ...linear..
Obviously a switch would then be employed to select one or t'other...with the first lnb in the chain retaining its lnbf feed ..

My question is simply ...why
..why has this not been tried before ?
Can anyone see why this would_not_ work ..
I'm happy to be shot down in flames ...and am also open to ideas and discussion ..

I'm also wondering why ..IF..this was practical ..why has no one produced it commecially ...
A bit like the Cband/KU combo used in the sates ..
That one only suitable for BUDs but obvious why ku would suffer ...but since the dual C unit would use a common correct sized waveguide..??
rgds
VS

 

[Analoguesat]

Hi friends ..
Currently sat in the shade of my 1.8pf ...enjoying the indian summer ;)
Gawd knows we deserved it ..

Its trying to rain up here . No sun seen at all so far today

 

[Vipersan]

Its trying to rain up here . No sun seen at all so far today

If its any consolation AS ...
Its starting to cloud a little here ..and I suspect more cloud and a little rain in the NorthWest by tomorrow ..
Them Londoners will have it persist till at least monday ...
Typical..

 

[Analoguesat]

No consolation at all

Enjoy the sun VS

 

[Lazarus]

I kid ye not, but it is beyond roasting here ............ even hotter than yesterday.

As for idle musings, most folk are rather more concerned with what flavour Ice Cream to have!

 

[Vipersan]

Make the most of it Gordon ...a little cooler here today than yesterday ..but then I am a little further west..
As to Ice cream ..
I'm old fashioned ..and only like the yellow lyons maid vanilla flavour ...
..anything else is just a perversion.. ;)

Had to open the shop ..but am sat outside ...
..not expecting any customers ..but can't afford to take the chance and close.
rgds
VS

 

[Llew]

I'm old fashioned ..and only like the yellow lyons maid vanilla flavour ...
..anything else is just a perversion.. ;)VS

Yuk. Had a Lyons Maid ice-cream in the cinema when I was a nipper. A god-awful oily-tasting cylinder job that sat on the cone. Made me sick and had to leave in the middle of Wizard of Oz. First Technicolor film I saw ( matched my Technicolour vomit)

 

[aceb]

If its any consolation AS ...
Its starting to cloud a little here ..

Cloud, wassat?

 

[Huevos]

Cloud, wassat?

I bet that pool is freezing.

 

[nelson_b]

Hi friends ..
Currently sat in the shade of my 1.8pf ...enjoying the indian summer ;)
Gawd knows we deserved it ..

Idle musings caused me to think about the practicalities of receiving both Linear and Circular polarities on on lnbf 'lump' at the focus of the 1.8 ..
It occurred to me that this item doesn't exist ..
Next question is ....why?
Here is a much simplified drawing of what my musings led to ..
effectively 2 complete c band lnbs joined in series with a dielectric prate seperating the 2 halves ..the rear lnb responsible for circular depolarization ...the front lnb ...linear..
Obviously a switch would then be employed to select one or t'other...with the first lnb in the chain retaining its lnbf feed ..

My question is simply ...why
..why has this not been tried before ?
Can anyone see why this would_not_ work ..
I'm happy to be shot down in flames ...and am also open to ideas and discussion ..

I'm also wondering why ..IF..this was practical ..why has no one produced it commecially ...
A bit like the Cband/KU combo used in the sates ..
That one only suitable for BUDs but obvious why ku would suffer ...but since the dual C unit would use a common correct sized waveguide..??
rgds
VS

hi -
i,m sure it will work -- but just how "well" - ????
only one way to find out i think---

i played around a little making my own - Cband/KU combo - 18 months or so ago - using a pauxis and a
darkgold and it gave better results than the DMX741U i bought from the USA --
but it still wasn,t up to much , to be honest

one thing i noticed with the DMX741U when i removed the K/u part from the back the C band performance went down until i blanked the back off with a disc of thin aluminium

i had to do the same with the pauxis after i,d finished experimenting -- as without a back it also gave a decreased performance .

that all i can contribute to the idea it would be interesting to try


cheers nelson.b.

 

[aceb]

I bet that pool is freezing.

22C today, was down to 18 last Monday but I've been letting the cover heat the top 6" and then circulating it. I'm surprised there's so much power left in the sun at this time of year.