[TEST REPORTS] Dual Band C/Ku Band LNB Combo LNBF With Best Performance?

empb

SU Team: It's All Good (Fausto v1.45/Newcamd/vplug
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I've seen a few of these over the past few years.

LNBF's that do C and Ku Band, and Linear (H/V) Circular (L/R) Polorization.

But because they still needed the Dielectric plate for switching linear plarisation to circular polarisation have bad reports on one side of the reception (K-Band or C-Band). [Anybody seen any electrical Linear/Circular switching ones?]

But this is usually because most Ku-Band signals are Linear H/V - which I think only 36°E has Circular L/R reception from NW Europe, UK reception area.

And a lot of C-Band signals are Circular L/R in the same reception area.

So leaving the plate in gives normal C-Band L/R reception, but weakened Ku-Band H/V reception and without the plate gives poor C-Band L/R reception, but normal Ku-Band H/V reception.

I still think it sounds like a sound idea to help alignment on smaller dishes (using weaker Ku-Band H/V reception to peak the dish for C-Band L/R reception).

Anybody out there had success? And with which model/s? (as some are rebranded)

I intend to give this a go, as my C-Band dish has definately moved in the high gale force winds we had the last two years (Winter 2018/9 and 2019/20). And with C-Band now leaving 5°W with it now being in inclined orbit. I only have stable reception from a few channels at 40°E, 20°E, 10°E at the moment, with occasional signal catches from 2.9°E, 3.1°E & 5°E at the moment.

lnbf1-jpg.118913
 

Ratzvan

Feed Hunter
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22,693
Hi,
I gave a look at your equipment and just let me do some considerations, before speak about your request.

Basically as I see you've two same size (110cm) moveble dishes, the upper one exclusively dedicated to ku band, the lower one with a C/ku band dual system.
Both seems to have a standard reception in ku band and of course low efficency in C-band (too small dish).
So with your system you can check two different satellites at the same time :thum: and occasionally have some passages in c-band and check situation.

I've pointed out this, because often we created habits and it's better if possible to not change them if the gains aren't worth the losses.

Unfortunatly your gains in C-band won't be ever enough :mad:
This to be clear.

Coming back to your DBS621 C/KU band lnb issue, this kind of lnb has been released just as older corotor replacement when satellite market has changed and receivers could no longer control polar rotor.
Same corotor had a high loss in ku band, but a good hold in c-band, while this new dual c/ku band lnb works really worse in boths :rolleyes:

As I know it seems to have been for many users only just a temporary solution before different choices.
I too bought one of them many years ago when I have to motorize my c-band dish only to have a more correct pointing on the central ku band satellite (at time I hadn't any good signal meter).
It was really very bad in both bands, so I remove it immediatly as useless.

So basically my suggestion if you want to keep the same equipment is to set a dual feed system on your lower dish, with a c-band dedicated lnb on the central focus and a ku band one on a secondary one.

You would have the disadvantage of double motor memories for ku/c-band same positions, but the advantage a dedicated lnb can give you more gain in c-band, while ku band lnb loss on the secondurary focus could be very low or zero, because you could susbstitute your loosy actual lnb with a more performant one (as an inverto ultra)

Eventually, if you adopt a dual feed, you've not to be worried about dielectric plate H/V lost.
In fact, your c-band system now would be for C-band only, so absolutly to be with a dielectric plate inside, because all satellites in your reception range have circular polarity (except 46°E and 38°E impossible for your too small size dish and 3°W, yet too arduous and of low interest).

Cheers
 

empb

SU Team: It's All Good (Fausto v1.45/Newcamd/vplug
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I was receiving a lot more in C-Band 3-4 years ago... the C-Band dish has definately moved. And Only has a standard C-Band LNBF on it at the moment, but is only getting regular stable C-Band from 40°E, 20°E, 10°E, 5°W.

The Technomate LNB I am using on the Ku-Band dish performed better than the Inverto Ultra I tried, but I am using it with a Technomate receiver.

Yes we did use a Ku-Band LNB to set up the C-Band dish originally, but the dish has always been too low and ajacent walls/buildings reduce its line of sight significantly. So it needs to be higher up the wall.

If 36°E Circular Ku-Band is still UK fringe receivable then too me the same brand C-Band LNBF, I am using now with added Circular Ku-Band may be worth the test while the price of these LNBF's has dropped.

I can still switch LNBF to C-Band only if that terrible (but Im not after a LNB that rocks in Ku and C Band, as long as it performs in C-Band and gets some Ku-Band).

The idea of being able to record from 28.2°E, 39°E, 19.2°E, 13°E Ku-Band from one dish whilst being able to look at a 2nd channel from any 54.9E to 30°W (which should be 45°W that cladding on the wall needs to be trimmed back as well) Ku-Band satellite appeals to me.

Whilst catching fringe C-Band from 40°E, 20°E, 10°E, 5°E, 3.1°E, 2.9°E, 1°W, 8°W, 11°W, 18°W, 27.5°W, 34.5°W(I don't think theres any C-Band active on Europe/Mediterranean Beams atm), 40.5°W, 45°W appeals.

With the dish as it is, only getting fringe C-Band reception from 40°E, 20°E, 10°E and thats just a waste of a dish.

Don't get me started about Ka-Band as well..... :D

But dont have a dual C/Ku Band LNB at the moment the DBS621-2 picture was the first dual LNBF picture I found on google, so which version of the dual LNBF you recommend? Or just to mount a 2nd Ku-Band dish on it (eg a offset Inverto?).
 

Rentakill

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Dual C/Ku Lnb Feed

Hi Guys.

I bought one of these exact feeds a few months back for use on a 3.8m Orbitron Dish fitted with Micromesh for KU.
For years i have used the 3.8m at different stages for C and Ku band - but never both at the same time.
Anyway after installing the Combo i found that C band performance was pretty much the same as with a dedicated C Band Feed.
The Ku Performance was where it struggled.
It would receive all your High power Transponders - but would not even show a snif of any lower power Transponders that my dedicated Invacom Ku feed would.
In my case i was looking at Intelsat 19 C/ku Services.
On Ku there is a 16APSK Service which my Invacom would resolve 18db when fully CrossPol/Nulled... The Combo C/Ku would not even see those services.

So in a nut shell... If your after out of Zone Transmissions The C/Ku probably wont cut the mustard.. Then again - what do you expect for $25...


Cheers:
 

bunkoknotty

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25
I have been trying to locate a dealer for their circular model as well.If you have any luck locating a dealer,please let us know.Thanks
 

Saphfire

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Is it worth it to RE install my old C BAND system here in Cyprus?
Any luck with the feeds?
I ve been away for may years from my hobby so i love to be back again
 

ro_54

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673
Is it worth it to RE install my old C BAND system here in Cyprus?
Any luck with the feeds?
I ve been away for may years from my hobby so i love to be back again
Take a look at the Oscam forum, to see the progress.
 
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