Astra 2E: Iberia & Balearics Reports

[joddle]

I assume you mean "Invacom" for the LNB - which actually should be about as good as its possible to get - but they don't like long leads so if the cable runs are big that could be part of your problem! Next issue is the feed-horn - are you using the correct one for that dish? I know many people like the Invacom adjustable version although I don't use on myself - but you can't use any old one - it has to be properly matched for the dish. The feed-horn is critical as it is responsible for ensuring the whole dish gets illuminated by the LNB. I have seen people use a so called "universal" Invacom on a PF dish and wonder why results were bad! - I trust your installer has used the correct PF kit! The final adjustments are the focus and skew also absolutely critical in Spain - a fraction of a degree making all the difference.

 

[PaulR]

Probably an Inverto LNB. But it does depend on which model, of course. And, as said, whether it's an off-set variety or a correctly set up prime focus assembly. The post seems to imply that the horn is part of the LNB so possibly not.

 

[Camping]

No the make is Inverto - just looked at it myself.
I see you have a 2.40 dish as well - how are you finding the UK terrestials?

 

[PaulR]

Camping, can you tell us what model the Inverto is and whether it has a separate feedhorn? If the feedhorn is an integral part of the LNB then it will be the wrong type for a prime focus dish and underperforming compared to a correct type.

If you are not sure you can upload a photograph here so we can look.

 

[joddle]

Yes I do have a 2.4 and get 100% SS and 100% SQ BUT I am in a much easier area than you. Please note the previous 2 threads as it does sound like you may be using the wrong type of LNB and feedhorn for your dish. The feedhorn and the LNB should be separate components and the feedhorn should have several concentric and perfectly circular scalar rings all at the same level. If your LNB and feedhorn are all one piece they are not correct for the dish - many people get confused by the term "universal" which describes offset systems not PF ones.

 

[altman]

on a multiswitch system, signal power is basically useless as a measure of comparison, quality is the goal here
think of it like having low power/low quality on a transponder(measured at the lnb), then adding a signal booster inline.. the result will be more power, but less quality than before.

I agree with PaulR on the feed issue as I experienced it myself, an old 0.6db lnb outperforming the champion IBU because the latter was designed for 0.7 F/D
and my primefocus dish is nowhere near that.
so the IBU was only "seeing" a portion of my 1.2m dish and the old one was using all of the dish.

your lnb should look like this (or white/red) with a feedhorn bolted to the front

the offset version looks like this:

BTW, Universal only refers to the band switching arrangement, as before one would need two LNBs, one for each band H/L and a polorotor for the polarity

 

[joddle]

Nice one Altman - the pic clearly shows how a C120 should look - i.e. have the ring of bolt holes on the front - if Camping's set up does not have that its not right.

 

[altman]

you guys type way too fast for me, no time to edit ;)

 

[joddle]

you guys type way too fast for me, no time to edit ;)

But the downside is I missed your added photo of the offset!!!! Nice one.

 

[Camping]

My techie says he gets better quality and hence less pixellation with the 1.80 dish than he does on the new 2.40 (2.30). I don't reckon the build quality is very good on the Farmaval compared to the Channel master, the arms are very flimsy.
Have included a photo of the old LNB as well

 

[PaulR]

Well, that's definitely the correct feedhorn. Have you tried positioning the LNB closer to the dish? The feedhorn may be too far back and losing signal. Don't lose your skew setting though, assuming that it's at optimum of course.

 

[Camping]

It is about as far back as it will go - he's tried various positions. I am a bit worried it is not aligned with the centre of the dish. How critical is that? As I said the arms flex quite a bit.

 

[joddle]

The alignment is critical - the LNB must point directly to the centre of the dish - if it does not you will lose loads of signal and get more noise. If the arms have been bent then there could be an issue - a quick way to check is to remove the lnb and replace it with a cylindrical torch pointing at the dish - if the torch beam is centred over the dish then the arms are fine but if not then you could have an issue. Also which feedhorn is being used? is it adjustable or fixed? and if fixed is it the correct one for that dish? If fixed it seems a bit long to be correct for a 2.4M dish to me but that could be the way the photo is taken. The issue is if the scalar rings are too close to the dish they cannot then "see" to the edge of the dish so you only get reception equivalent to a smaller dish. When I had an issue many years ago on 2D I tried an adjustable feedhorn and found it improved reception greatly. However I have never used an Inverto nor a quatro - LNB only a quad steup.

 

[altman]

It seems Inverto doesn't even produce that version any more, still available through distributors tough
I think the most correct one should be: http://www.inverto.tv/products/product.php?section=1&id=84

and the feedhorn should be none other than the Famaval, as feedhorns should be mated to the dish

EDIT:
on offset dishes, any one is a "sat tech", you buy the right size dish, get a good lnb, align and bobs your uncle.
on PF, there is a lot of "black magic" involved to buy the correct components, then set them up properly.
I've installed thousands of dishes over 20 years, but I'm still learning new things every day, and consider myself an "apprentice" on PF

 

[kota]

@ camping : that feedhorn does look too far back indeed. Also, the aluminium arms can be easily setup. Simply tighten/untighten all the three fixing bolts at the dish edge until you've reach max signal.

This is the right famaval feed for the 1.80m PF dish which I still use. Photo taken while experimenting with an offset lnb I c120 butchered some years ago

 

[joddle]

@kota: is the 1.8 feedhorn the same as the 2.3? I would have thought not but cant see any info on the Famaval website to say
one way or the other.

 

[Huevos]

Take a photo of the feedhorn looking up it so we can see the scalar rings.

And TBH I can't believe it. 900 euro satellite dish with a 20 euro lnb. Say no more.

 

[joddle]

Re the LNB - why was that one chosen? And what would Huevos have used? I have always stuck with the Invacom.

 

[kota]

@kota: is the 1.8 feedhorn the same as the 2.3? I would have thought not but cant see any info on the Famaval website to say
one way or the other.

I'm afraid so. This is the same feedhorn that came with a 2.30m dish I also used to own years ago. I also have one of these IRTE ones lying around which I still have to try on my present 1.80m. I'll report back once the weather improves.

 

[Huevos]

Got to say reading about this 2.4m Famaval install is pretty depressing.

Camping, I have set up more than a thousand of those dishes and even more Famaval 1.8m. And I can tell you the Famaval 2.4m dish out performs the 1.8m CM by a country mile. If your dish isn't I wouldn't be looking for a fault with the dish.

Absolute best feedhorn is the latest Famaval with 5 concentric rings. Same feedhorn for 2.4m and 1.8m because they both have the same f/d ratio. The 2.4m dish needs the feedhorn pulled out all the way almost touching the black plastic holder. Sometimes even that is not far enough and they need a stack of washers under the holder to get it further from the dish. In my opinion the only LNB to use is the Invacom (quattro for a multiswitch setup). And lastly sometimes the 2.4m dish need shimming in places between the backring and the dish to get the last drop of performance out of it.