LNB & Feedhorn Question

radical

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My Satellite Setup
150 Cm Focal Nokia Dish.
Topfield TF-7700 HSCI.
LNB: Invacom C120 single.
Feedhorn: SMW-XM 140
Cables: Edison >120
My Location
Sweden
Hi,

I have some problems with the reception on my motorise sat-system, after a while of watching..the picture jumps out of signal.

It seems to me there is some interference between the V&H signals?

I have the Invacom Single SNF-031 C120 LNB combined with an older SMW XM-500 Feedhorn.

Does anyone know if these combination could be the cause of this problem?

Thanks
 

Llew

cerca trova...
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My Satellite Setup
Triple Dragon, Dreambox 8000, Echostar AD3000ip, TBS6522,6925,6983 PCie cards.
Gibertini 1.25m motorised dish driven by the AD3000, with either Inverto BU Quad or Norsat / XMW Ka LNBs . SMW 1.05m + 3 other dishes. Speccy: Promax HD Ranger+
My Location
The Flatlands of East Anglia
Thh XM-500 is a circular feedhorn ideally mated with an SMW dish. This is almost certainly why you are experiencing polarisation problems.

How have you coupled it to your Invacom?

Llew
 

radical

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My Satellite Setup
150 Cm Focal Nokia Dish.
Topfield TF-7700 HSCI.
LNB: Invacom C120 single.
Feedhorn: SMW-XM 140
Cables: Edison >120
My Location
Sweden
Llew said:
Thh XM-500 is a circular feedhorn ideally mated with an SMW dish. This is almost certainly why you are experiencing polarisation problems.

How have you coupled it to your Invacom?

Llew



Yes the XM-500 feedhorn is circular and for focal dishes, but so is the Invacom SNF 031 Single LNB.

The flange is C120 and it is fitted to either the older XM-500 or the never SMW XM 140 without problem.

What i get out from the spec of the feedhorns F/D. there shouldn't be a problem really?

What i don't get is what combination of feedhorns and LNB are compatible then?

The Invacoms feedhorn are to thin in diameter, but of course a handyman like me could always fix that :)

I just want the best reception for all channels

Any recommendations of compability?

Thanks
 

Llew

cerca trova...
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My Satellite Setup
Triple Dragon, Dreambox 8000, Echostar AD3000ip, TBS6522,6925,6983 PCie cards.
Gibertini 1.25m motorised dish driven by the AD3000, with either Inverto BU Quad or Norsat / XMW Ka LNBs . SMW 1.05m + 3 other dishes. Speccy: Promax HD Ranger+
My Location
The Flatlands of East Anglia
So you had no problem fitting the feedhorn to the Invacom? I found my XM-604 4-hole fixing didn't align with the Invacom perfectly, and had to leave one screw out. Still a good seal though on the O-ring.

Don't know the best feedhorn for your PF dish, only have offset ones.
 

Robbo

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Your XM-500 hasn't got the integrated RHC/LHC integrated depolariser by any chance, as I imagine this would affect performance?

_http://www.smw.se/res/pdf/feedhorn1.pdf

Robbo:)
 

radical

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My Satellite Setup
150 Cm Focal Nokia Dish.
Topfield TF-7700 HSCI.
LNB: Invacom C120 single.
Feedhorn: SMW-XM 140
Cables: Edison >120
My Location
Sweden
Robbo71 said:
Your XM-500 hasn't got the integrated RHC/LHC integrated depolariser by any chance, as I imagine this would affect performance?

_http://www.smw.se/res/pdf/feedhorn1.pdf

Robbo:)

Ok thanks all satpros.
I was thinking of fitting the XM-140 with the Invacom C120 SNF-031.

What LNB,s would be better then Invacom SNF 031 if.. i'm after a better performance for all freq ?

My current dish gives me about 38 Eirp in KU-band from where i live.If i could get it better in performance with a better feedhorn and LNB it would always be appreciated.The F/D on my dish is 0.4. Amplifing 11.3Ghz is 43,3dbi.

The offset dishes is said to get better performance then focal ones. How much difference % are e talking about here with the same size dish?

Is a wider feedhorn like invacoms give better reception&performance if fitted correctly then the XM-140?

I thought i might get it to fit my feedhornholder with some special made adapter.

Thanks
 
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