LNB Universal linear + Circular?

[enb141]

I would like to know if there's a LNB that have Universal Ku (10.70 - 12.75) and also Circular (12.2 - 12.7)


The invacom QPH-031 and QPF-031 doesn't has Universal Linear (11.7 - 12.2) (correct me if I'm wrong)

The Digiwave DGL-1189L and DGL-1189S doesn't seems to have quite good their specs on their website

http://www.invacom.net/documents/Quadpolardatasheetwhite.pdf

Digiwave Satellite Wholesale Distributor - MPEG2 Digital Receivers, LNBFs, Digital Equipment, Stab Motor, Moteck Motor, Switch, CCTV Camera - Wholesale Satellite Distributor - Wholesale only

Digiwave Satellite Wholesale Distributor - MPEG2 Digital Receivers, LNBFs, Digital Equipment, Stab Motor, Moteck Motor, Switch, CCTV Camera - Wholesale Satellite Distributor - Wholesale only

 

[enb141]

Can an Linear LNB catch circular signals?

I would like to know if is possible to grabb Circular signals with an Universal Linear or Linear LNB?

 

[harshness]

No.

The ability to discriminate between the various polarities (horizontal, vertical, circular) is what makes polarity useful. The same frequency can be reused with a different polarity mostly without interference.

 

[brentb636]

I would like to know if is possible to grabb Circular signals with an Universal Linear or Linear LNB?

Yes, you can receive circular signals on a linear lnbf. The problem is that the level will be lower, and you can't discriminate between Right and Left polarity, so you can get a lot of duplication. I used to do it frequently when there were unencrypted DISH channels in the freq range of a linear lnbf ( 11700-12200) . Right now, if I were to blindscan 83W Ku, I'd also pick up the 12224 tp from neighboring 82W, the Canadian circular polarity bird.

 

[Mikey11]

yes a linear lnb can pickup some circular signals/TPs....but not reliably....i have done it in the past

 

[enb141]

Ok, now I got it, so in the opposite way (Circular LNB getting Linear Signals) I think is the same principle right?

 

[Mikey11]

no...there is no such thing on the market....the invacom is the only linear/circular lnb out there but will only do the high band linear 11.7-12.2....the digiwave 1189 series are circular lnbs ONLY!!....do not be fooled by their advertising they will NOT pickup any linear signals AT ALL!!!

 

[Mikey11]

Ok, now I got it, so in the opposite way (Circular LNB getting Linear Signals) I think is the same principle right?

no its not the same....a circular lnb will not pickup linear signals....

 

[brentb636]

Maybe ? I've never had a circular lnbf in the North American linear frequency range to try it out. Remember that the circular birds put out a lot more power than the linear satellites. Capturing a linear signal, with a mis-matched lnbf would be much more difficult than the earlier example. Perhaps with a 1.8M offset dish , you could experiment .

 

[FaT Air]

I pick up a strong circular C band TP on I-707@53°W without the dielectric plate installed in the feed (DMX241) It scans it in on both H and V polarity. So it is possible, But the chance of an opposite polarity signal interfering is high as there's no way to discriminate between polarities. Install the dielectric plate and that problem is solved.
EDIT: I type too slow and edit too much, 5 or so replies in the time I composed one. wow.

 

[enb141]

I see, so with an offset dish the only LNB available right now is the Invacom QPH-031 so that means that getting circular and linear signals is limited due to the lack of LNBs because most LNBs are or circular or linear but there's only one circular + linear LNB that is the Invacom.

 

[brentb636]

I have an Invacom qph-031 and it works fine within it's range. It's actually a dual circular and a dual linear packaged in the same housing. I'm not sure that somebody hasn't tried to clone it, though, so there might be a different mfg one out there somewhere.
If you actually had a circular satellite that you wanted to concentrate on, you could simple use a Dish 500 with circular lnbf and scan the bird. The situation becomes more complex if you want to motorize a single dish and get both linear and circular signals. That's where the Invacom quad polar, is useful.

 

[enb141]

Totally agree with you, the problem resides when you try to use a motor or pick another satellite that needs linear LNB so now the question is if is possible to mod the invacom to get Universal linear signals as well?

I got an invacom SNH-031 so maybe joining this two lnbs to get the real universal LNB + circular that would be cool, not cheap but at least an option.

 

[enb141]

After reading a while I've found that the DG are only circular with higher range than normal Circular LNBs and as you said it doesn't gets linear signals.

By the way I'm wondering how hard could be to mod the invacom and make it universal linear + circular.

 

[Mikey11]

If the dish is going to be motorized, then you could use a universal linear lnb in the dish holder (center position) and mount a circular lnb next to it, I have done that before, USALS will not work for the circular lnb though

 

[SatelliteAV]

It would be beyond the average person to modify the QPH-031 for universal band reception.

We had originally discussed making the unit available as a universal, but decided against it as the LNBF was originally developed for simultaneous usage with DSS/DBS and FTA receivers. I exited the project after the QPH-031 production and the product line was not developed further.

If you require both universal and circular, side mount a circular to the left or right side of the centered universal and modify the satellite position in the satellite list to continue USALS positioning. The circular signals are so strong that the slight offset will have negligible effect on reception.

 

[Pixl]

If you require both universal and circular, side mount a circular to the left or right side of the centered universal and modify the satellite position in the satellite list to continue USALS positioning. The circular signals are so strong that the slight offset will have negligible effect on reception.

Brian,

If I am West of my true South sat, do you also have to mount the sidecar slightly higher or lower than the centered lnb? And then what happens if I go East of TS?

 

[brentb636]

"The circular signals are so strong that the slight offset will have negligible effect on reception." An excellent point. You can practically put in circular with a coffee can !.

 

[mikekohl]

On a motorized system, you would put a circular LNBF at the same height as the center LNBF, and move east or west to peak the circular signal. I have used a hose clamp lots of times to make this happen. Now if you are on a fixed system, think like a mirror. If the offset satellite has a higher incoming elevation, and is east of you, put the circular LNBF lower and west. It may require spacers to get things perfected, but at least circular is forgiving in polarity---it doesn't matter.

 

[enb141]

About using two LNB, one at the right or left side of the other well as far as I know the minimum distance is like 4° in other words if you stick each other the distance in satellite measures is 4° (Correct me if I'm wrong) but since I'm too far away I think the signals will be to weak so maybe is not gonna work.

I also tried picking two Linear satellites with a ESX521U-AM but I had no luck (those two satellites have pretty high signal here).

So that's why I was thinking about modding an LNB to get both Universal Linear + Circular but not sure if is so hard.


[LNB Linear][LNB Circular] = [61°W][65°W]

So in other words I have to options:

1) Get a stick play around and put the circular closer to the linear LNB that is on the center
2) Modify the Invacom or any other LNB to get both signals in one.