MULTYTENNE disecq config

[LeBelge]

I'm strongly considering asking to exchange it for an 85cm dish and 4 LNB's ...

98 cm dish -> 28°E - 19°E - 16°E - 9°E - 7°E

https://prikachi.net/images/2024/03/29/7LNB.jpeg

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110 cm dish -> 53°E - 45°E - 42°E - 39°E - 33°E - 28°E - 24°E

https://prikachi.net/images/2024/10/06/sas7Lnb.jpg

 

[Captain Jack]

(forget Astra 3)..

Do you lock ANY transponders on Astra 3? The one you picked in the screenshot is probably the worst you could have picked. This is because of its extremely low SR of 1000. It takes a good few seconds to get a lock after every adjustment. Also, looking at Lyngsat, it's actually empty, so you won't get anything there anyway.



Try this - strong signal in the UK. You should have few issues locking that.



That said, a T90 would be perfect for you. I have one and picking up most things between 28E and 15W. Some weaker satellites on the edges of the dish are borderline but 13/19/23/28 won't be an issue.

There's also Cahors BIG BISAT dishes, which are much prettier than T90, but come with a narrower range. And a bigger price tag.

 

[D4ftpunk]

There is a specialised dish, for multiple LNB's, called a Wave Frontier 90cm.

If going for 4 LNB's, on an 80cm dish, you might need slim LNB's, also known as Bullet LNB's.

Please post results for 23.5E

Any particular transponder for 23.5E? I think it's the weakest but also is the one I don't care about.
EDIT: just saw 11739V, gonna try after this scan.

Ended up with a 9.0 degree skew in the end for those interested (may even be 8.5, I didn't take a protractor up with me and just used a plank and a digital level). Thanks @a33 for the starting point, it made a HUGE difference.

The stats I posted earlier are holding true, although it's beautiful clear skies here. I guess this dish "will do", but my advice to those who are interested, is... don't. Although it's in theory simpler to mount and align than a multi-lnb or motor setup. In practice it's actually a lot harder and a lot more fussy. For some context, I aligned a 65cm dish to Astra 1 in about 90 seconds, there was a huge margin of swing before I lost signal... this MULTYTENNE dish took me hours and if you move it 1mm out of alignment, it has dramatic impact.

 

[Captain Jack]

I aligned a 65cm dish to Astra 1 in about 90 seconds, there was a huge margin of swing before I lost signal... this MULTYTENNE dish took me hours and if you move it 1mm out of alignment, it has dramatic impact.

That's because you're aligning onto 4 different satellites at once, so it has to be perfect. It took me weeks and weeks to of tinkering to align my T90. In contrast, it takes me 20 minutes to align a motorised dish.

I daresay, T90 is easier as each LNB can be adjusted individually. Here, it's all fixed with little in the way of adjustment to be had. I am surprised it doesn't offer skew adjustment, given the wide catchment area of the satellites the dish is designed to receive.

 

[D4ftpunk]

I'm very much up for a motorised dish to accompany this. Only issue is it'd push my L bracket out (that I use for my main dish) another 20-30cm and I don't have that clearance, if I go for a lower protruding L bracket, I'd probably end up hitting the wall when rotating all the way to the edge. Hence stuck with this setup and some manual re-alignments of my main dish when I fancy it.

 

[Captain Jack]

Motorised dishes on DiSEqC motors tend to sit quite far away from the wall given the bracket + motor length + dish bracket itself. It can easily double the distance of the wall mount without trying. And there's always limits you can set.

 

[D4ftpunk]

interesting. I think my current L Bracket is maybe 30cm minimum protruding from the wall. perhaps I can find a 10cm or similar to replace it with given the extra protrusion a motor would give.

Loading…

www.amazon.co.uk

This is 15cm and looks to be as small as possible. Hopefully still enough space to bolt a dish/motor to.

 

[Captain Jack]

I would really advise something like a T&K bracket - much stronger than the flimsy L bracket and easier to get the pole 100% vertical (a must in motorised systems).

 

[D4ftpunk]

Just to add an update here (for those considering)... Hotbird on this dish (LNB 2) degrades significantly under any rain or heavy cloud cover, to the point the weaker transponders just don't work at all. In clear/moderate weather it works however.

 

[D4ftpunk]

As silly as this looks… I found it on a Dutch forum and it actually works:

 

[a33]

Ended up with a 9.0 degree skew in the end for those interested (may even be 8.5, I didn't take a protractor up with me and just used a plank and a digital level). Thanks @a33 for the starting point, it made a HUGE difference.

Yes, it is nice to have an accurate calculator for that.


I developed it, after noticing that multifeed skew calculators often had rather differing outcomes, with often unknown calculation methods, or clearly incorrect calculation methods (for instance the methods based on azimuth difference and elevation difference).
It took me quite some time to discover this correct calculation method, and work it out mathematically.

If you just want a rough estimate for multifeed skew angle: take the ('theoretical') skew value of the central satellite position (above the arm). 'Theoretical' value in the sense, that you don't take the possible pre-skew (for for instance Astra and Eutelsat satellites) into account.
This estimate works quite well for more or less "symmetrical" multifeed setups, where the central satellite position is about in the middle between the extreme satellite positions. For more "one-sided" multifeed setups, it is a bit less accurate, but still usable.
But now that I have an exact calculator, I don't need estimates anymore!
(Why use an estimate, when you can have the exact value?)

As silly as this looks… I found it on a Dutch forum and it actually works:

Yes, I advised that too: Found an ideal Monoblock, but can't find anywhere that sells it!
And linked it also here in this thread, in #12.


Are you still going to keep the Multytenne, after all you've already experimented with it?

Greetz,
A33

 

[D4ftpunk]

Tbh, I’ve paid for it, so will keep it, am going to supplement it with a 65cm similar technisat square dish on a motor next week for all other sats and reliability. Need to find a solution for “as close to wall as possible” mounting.

It I could start again… I’d probably just have gone 65cm motorised next to my existing old sky dish. You live and learn I guess… I’ll be down to 2 dishes once all done, remounted and tidied up… but they’ll look nice and give me 3-4 inputs into my quad tuner box.