Linear\circular LNB Question

[Mr Tony]

In doing more reading on these L/C LNB's most are designed for circular signals only and wont work on linear

They work on the DBS sats and 118.7......so we know what market they want

 

[Anole]

Yea, good point, 118.7° uses 10750 LO, but is circular!
I really can't think of much use for one of those, other than as you said: convert it to linear and forget it. -

I guess what I was thinking about may have been the clone of the Invacom QPH-031.
(Which actually works quite well as linear/10750 and circular/11250)
There were some LNBs sold by ignorant or unscrupulous dealers AS the real Invacom part.
Seems like those didn't live up to their claims so well , either.
All the more reason we need little reviews to point to, so we make sure we all get the right stuff! -

 

[Mikhel]

Yup, it has a noise figure of 0.5, while most of recent ku lineal LNBs have 0.2 or even 0.1, a universal Ku LNB usually has 0.3 db.

It should be clarified that your statement is made from "Published Specs" and not something you know or have tested.

My experience with that LNB left much to be desired, A LOT, it was marketed as a Lineal/Circular LNB and until now that i've read Iceberg's post from early this year, i've figured it's not a Lineal/Circular.

I tried to get the channels with it at 123ºW but it was pretty much awful.

I just decided to tell the store were i bought it that it didn't work as specified since i could not get a single lineal channel, the guy at the store contacted his dealer and the response they gave him was "oh it's not a lineal/circular, the package was wrong, we sent you low frequency circular LNBs designed for people who get tv circunventing DN's security to watch channels at 118.8ºW" (as in h@ckw@re).

They offered my money back so i ordered an Invacom Lineal/Circular and it was good, then again, it's a good brand, and the installation is running really well, or at least that's what i've been told.

Before that I compared the Digiwave to a 0.1db Eagle Aspen, a 0.2 db Chaparral, and an older 0.5 db Chaparral Quad, the Quad had a very poor response, while the other two were really good.

So in restrospective, in my experience using commercial grade LNBs:
0.1db > 0.2db > 0.5db

Nowadays i've been hearing a lot about a spitfire lineal LNB but i had not tested that one.

In the other hand, a friend told me about this same LNB, he was interested in catching 118ºW, and what i heard from him is that he configured it as 10500 instead of 10600 or 10750, you know, like those directv latino LNBs, and alas, he got what he wanted.

M.

 

[GreatFTA]

Yea, good point, 118.7° uses 10750 LO, but is circular!
I really can't think of much use for one of those, other than as you said: convert it to linear and forget it. -

I guess what I was thinking about may have been the clone of the Invacom QPH-031.
(Which actually works quite well as linear/10750 and circular/11250)
There were some LNBs sold by ignorant or unscrupulous dealers AS the real Invacom part.
Seems like those didn't live up to their claims so well , either.
All the more reason we need little reviews to point to, so we make sure we all get the right stuff! -

Anole, what about the Invacom SNH-031? Would it so circular as well?

 

[GreatFTA]

Would any of those old Primestar LNBFs work on circular as well? I got few of them laying around.

 

[1ADAM12]

Would any of those old Primestar LNBFs work on circular as well? I got few of them laying around.

My P* lnbf is linear.

Their is a vendor on eBay from canada that sells a circular lnbf for under $15 and works very good for me. I offset it 6 degrees on a motorized dish and can jump from 119 to 125 via switch setting. I believe it is advertised as 119 & 118 lnbf.

 

[1ADAM12]

My experience with that LNB left much to be desired, A LOT, it was marketed as a Lineal/Circular LNB and until now that i've read Iceberg's post from early this year, i've figured it's not a Lineal/Circular.

In the other hand, a friend told me about this same LNB, he was interested in catching 118ºW, and what i heard from him is that he configured it as 10500 instead of 10600 or 10750, you know, like those directv latino LNBs, and alas, he got what he wanted.

M.

?

 

[Anole]

Anole, what about the Invacom SNH-031? Would it so circular as well?
...Would any of those old Primestar LNBFs work on circular as well? I got few of them laying around.

The QPH-031 is the only Invacom designed and sold for operating circular (so far as I know).
It does circular, and Standard linear
All the other Invacoms are Universal linear. (I like the SNH-031 )

As for any linear getting some circular, yes, because the signal levels are so high, some linear LNBs can get some of the lower channels.
You might have to blind scan, but some can get the signal.
Not a reliable nor repeatable method, so not recommended, of course.



edit: Probably Too Much Information (tmi) -
Well, if you wanted to modify a Primestar LNBF, I suppose you could shove a bit of teflon or few layers of credit card down its throat, at a jaunty angle, and increase the circular performance.
I can't imagine anyone actually doing that, but technically it's possible.
As for the wrong LO frequency, I won't get into changing that.
(Search for a discussion of modifying a circular DirecTV or DishNetwork LNB to linear, for more info, if you are a masochistic. )

 

[Mr Tony]

most folks just find an old DirecTV LNB and use it for circular

 

[Mikhel]

My experience with that LNB left much to be desired, A LOT, it was marketed as a Lineal/Circular LNB and until now that i've read Iceberg's post from early this year, i've figured it's not a Lineal/Circular.

In the other hand, a friend told me about this same LNB, he was interested in catching 118ºW, and what i heard from him is that he configured it as 10500 instead of 10600 or 10750, you know, like those directv latino LNBs, and alas, he got what he wanted.

M.

?

There are low frequency circular LNBs, those were made for Japan and 'Latinoamerica', those low frequency LNBs work at 10500.

So if you want to catch 118.8ºW just for the sake of it and see if there's something ITC, and also get 119ºW, you'd need to get ahold of one of those DTV Latino LNBs, they do have less gain than a normal circular LNB. And from what a friend told me, that same Digiwave was working fine at 10500, don't have a way to confirm it except what he told me.

If your question was regarding the first part of what you quoted, well, i posted that just to let you know that my statement had basis on tests i made, after 20+ years in this hobbie i've came to test newer things just for the sake of it (the exception being DVB-S2 until a receiver catches my interest AND it's MLB season again).

M.