Comparison of LNBs on Channel Master 1.2m -- with and without feed horn -- Invacom, Inverto, SMW, Sm

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felixg

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Franky
Thanks a Lot!
I ordered invacom twin LNB from England Regarding your recomandation and comparation report.
Will Try and update you.What are you suggest regarding depolarasation plate for my FH?and what the demantion from your point of view?
Best Regards
Felix
 
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felixg

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felixg said:
Franky
Thanks a Lot!
I ordered invacom twin LNB from England Regarding your recomandation and comparation report.
Will Try and update you.What are you suggest regarding depolarasation plate for my FH?and what the demantion from your point of view?
Best Regards
Felix
Click to expand...
Hello Franky
After one month of preparations and lot of mechanical defines and dish cleaning,today i am ready to start my tests.In the first stage i installed the dish on huge tripod due to i would like to test all combinations with LNB on the ground, before wall installation.
I will ready today night and will appropriate to receive from you couple of recommendations:
  1. What frequency of local oscillator i need to define in my receiver using Invacom TWF-031 (right now i am using 10750)?
  2. What the right way to install depolarization plate insight the FH relation the LNB(there are two pins insight the LN:cool:?And how deep the plate should be in the FH.My feed horn has a special grooves for depolarization plate.
Will very appreciate for you recommendations
Best Regards
Felix
 

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Analoguesat

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Its a universal lnb so the LO should be 9750/10600
 
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As I'm new on here ..... I thought I would post my LNb test results .....recently ....changed fron a Opticum octo 40mm LNb ......to a raven feedhorn and invacom c120 quatro lnb ....connected to a Opticum 12 output multiswitch .......and got a signal quality improvement of about 20 %.....quite a surprising increase ....!
 
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Steve Steve said:
As I'm new on here ..... I thought I would post my LNb test results .....recently ....changed fron a Opticum octo 40mm LNb ......to a raven feedhorn and invacom c120 quatro lnb ....connected to a Opticum 12 output multiswitch .......and got a signal quality improvement of about 20 %.....quite a surprising increase ....!
Click to expand...


Exalant.Did you connect to 36E sat or deferent?
 
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Steve Steve

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sorry ..I should have made that clear.....on the Astra 2F at 28.2....the signal here drops alot at night and can be a prob 8pm-12.......
 
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Steve Steve said:
sorry ..I should have made that clear.....on the Astra 2F at 28.2....the signal here drops alot at night and can be a prob 8pm-12.......
Click to expand...
OK are you use linear polarisation?
 
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Yes he is. Circular ku band can only be found on 36e Russian beam. No-one in western Europe gets it due to footprint.

Sent from my HTC One X using Tapatalk 4
 
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Captain Jack said:
Yes he is. Circular ku band can only be found on 36e Russian beam. No-one in western Europe gets it due to footprint.

Sent from my HTC One X using Tapatalk 4
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I'm new on here.....but ...sorry ...what are you replying too...???...it makes no sense to me....?
 
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It's refering to post 27 where felix asked if it was linear polarisation.
 
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Steve Steve

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Can you explane "linear polarisation"... in satDIY,ers English .....?.....thanks in advance....
 
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Captain Jack said:
Yes he is. Circular ku band can only be found on 36e Russian beam. No-one in western Europe gets it due to footprint.

Sent from my HTC One X using Tapatalk 4
Click to expand...

Hi what about Franky?He compare signals with diferent LNB on 36E.....
Best Regards
 
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Franky_D said:
Hi felixg,

I checked the footpring of 36E for your area and it does not look very promissing. Just need to give it a try to see how good of a signal you can get. I can suggest to start checking liniar signal from 36E with the hardware you've got already, based on that you can get a basic idea if circular will be any good, you can find measuments for both circular and liniar in my tests - for relative comparison. If that would give some positive results, there would be space for experiements to optimize the circular signal reception - from my expereince good/optimized depolarizing plate inside a feed horn can give significant difference.

I've tested various plates with CM matching feedhorns: original SMW plate, Inverto plate (actualy in combintation with both Inverto c120 and Invacom c120), tons of self made one. The best results were achieved with self made plate from a circute board 0.2 mm thick (by etching a layer of copper). :) It is a bit manual and complicated technology. I can send you one for your tests.

I forgot to attach pictures last time, see attached now.

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Cheers
Click to expand...

Dear Franky.I actually installed the dish and provide couple of tests with deferent plastic plates .Right now the signal is not so strong .I have 1,2m dish with circular LNB and today its look like the same signal level for 1.8m .
Could you please send me your plate to test it ?Will very appreciate you
Thanks a lot
Felix
 
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Steve Steve said:
Can you explane "linear polarisation"... in satDIY,ers English .....?.....thanks in advance....
Click to expand...
Linear is horizontal or vertical. Perhaps an analogy...

Imagine two people with a skipping rope between them. If they shake the rope up and down to set up a wave - that's vertical; from side to side it's horizontal.

Now imagine them waving their arms in a circle that's the equivalent of circular polarisation. This also comes in two varieties depending on whether they rotate their arms clockwise or anti-clockwise.

Any help?
 
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Steve Steve

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cheers .......i think i see what you mean......so i don't have linear polarisation....then..!!.....lucky me........because it sounds like a bad medical condition....:))
 
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Nowadays circular polarisation is mostly confined to C band transmissions, the few in Ku band that exist are mostly beyond our reach in Europe.

As a matter of interest circularly polarised transmissions (either type) can be received on a linear LNB and linear transmissions (either type) can be received on a circular LNB. The problem is that the "wrong" type of LNB can't discern between the other two different types so it loses about half of the signal. In a nutshell it performs very badly.
 
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