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MTJR
12-04-2011, 09:34
It occurred to me that whilst there is quite a lot of information on the net about the physical side of setting up a dish (hanging it on the wall), there's very little about the technical side (tuning).

What I noticed when doing my own recently is that getting the dish pointing at the right satellite can be extremely difficult even with a Satellite Finder. What a Sat Finder won't tell you is what satellite you're actually pointing at and the apparent variances in the strength of signal don't help either.

Would I be correct in this analogy?

Let's assume that a shower head is the signal coming from the satellite and a bucket is the satellite dish. Dependant on the placement of the bucket (dish) you may or may not catch all of the shower water (sat signal). As you move the bucket (dish) you catch more of the water (sat signal).

If we assume this to be correct then dependant on what channels you are NOT receiving should give an indication as to which direction your dish needs to be moved.

Have I got this somewhere about right?

John

Kymmy
12-04-2011, 09:41
You also need to be aware that it depends on what group of sats you're trying to find.. Also I've noticed that sat finders react differently dependant on the polarity of the LNB as you're measuring a combined output and the transponders on lets say V might have a weaker signal than those on H. Also be aware that for example Astra 2 isn't just one sat but a group of sats all manoeuvring inside of a box shaped area in space, if you get the edge of one sat it doesn't mean to say that you'll get all the sats..

MTJR
12-04-2011, 10:54
Of course, I forgot the fact that when people refer to Astra 2 we're talking about a cluster of satellites as opposed to just one, which gives a bit more credibility to my "shower" theory.

I think I now need to do some cross referencing with the channels I'm missing and to which satellites in the cluster they refer to.

I feel a tutorial coming on.

John

nodrogd
14-04-2011, 16:35
Sky & Freesat use the Astra 2 cluster at 28.2E and Eurobird 1 at 28.5E. The dish needs to be optimised to receive both.

MTJR
14-04-2011, 22:24
Yeah. I know that. I was just trying to cobble something together so that, let's say someone manages to get BBC1 HD but not Zone Horror for example, so knowing that satellites they ARE receiving and which ones they're not they would then know to move the dish more to the east or west. It's a rough example but that's the general gist.

John

Chris
14-04-2011, 22:41
<pedant>

It's just called 'Horror' these days. They dropped the 'zone' when CBS re-branded the whole package. There's no Zone Romantica or Zone Thriller any more either ... there's CBS Action, CBS Reality, CBS Drama and, for some reason, Horror with no CBS prefix.

</pedant>

Anyways ... the CBS channels are on Eurobird 1, which has a far larger footprint than Astra 2D (as used by the BBC). I would have thought your scenario would be more likely reversed, i.e. you could get Eurobird channels like CBS and find you're missing the BBC.

IIRC the advice when the BBC started moving to the more narrowly-focused beam on Astra 2D was that people with less than perfectly aligned dishes risked finding their BBC reception compromised. I don't know how wide a problem this turned out to be though.

MTJR
14-04-2011, 22:59
Hmmm. That's a bit odd then.

The "normal" UK stuff (BBC, ITV, 4/5) are my best signals. Although for reasons known to someone much wiser than I am BBC4 only ever seems to broadcast a black screen (very arty) even though the signal quality is as good as BBC3 (which is on the same transponder I believe).

CBS Drama and CBS Reality do show up (bit low on quality but very watchable picture) but CBS Action and Horror are a no-go.

It's not that I particularly want to watch any of this stuff. I just like the kit to work properly so I can prove to myself I can actually do it without getting a bloke in. In addition, I'd like to pass something on to the people who come along after me and think (like I did) what a good idea putting a satellite up would be.

John

Chris
15-04-2011, 09:34
No CBS Action? :Yikes: That means no original, digitally remastered Star Trek. How do you cope? :p:

I really couldn't say what the reason for your variable reception is ... could do with a radio-communications expert to show up.

/waits for Kymmy to reappear ;)

Kymmy
15-04-2011, 10:47
Sounds like the HI-LO band switching via the 22Khz tone might not be working..

How long is the Co-Ax? What type is it? And have you recently cleaned up the conenctors. And most importantly have you got the LNB tone settings right on the box..

Chris
15-04-2011, 10:48
:wavey: Good morning! :D

MTJR
15-04-2011, 12:16
No CBS Action? :Yikes: That means no original, digitally remastered Star Trek. How do you cope? :p:

Surprisingly well! No adverse affects to date although I do find myself making strange wooshing noises when I get close to a door.

---------- Post added at 12:16 ---------- Previous post was at 12:13 ----------

Sounds like the HI-LO band switching via the 22Khz tone might not be working..

How long is the Co-Ax? What type is it? And have you recently cleaned up the conenctors. And most importantly have you got the LNB tone settings right on the box..

The cable is a 10m white one I got from B&Q.

When you talk about connectors do you mean the little strand of cable that pops out of the end? Either way, the answer would be no,

I've no idea what a LNB tone setting is or what I'd do with it. It would be the same setting as the one it came with. Next time I get a chance I'll see what I can find in the menus.

John

Kymmy
15-04-2011, 13:17
The LNB has two things controlling it..

1# Is the voltage which not only powers the LNB but also switches the LNB polarization (13v for Vertical and 18v for Horizontal) If broken then you only get half the channels.

2# 22Khz tone (used on Universal LNBs). This switches the Internal oscillator from 9.75Ghz (no tone) to 10.6Ghz when the tone is switched on. If the tone is broken or degraded by the cable/connectors then you will not be able to receive channels on higher frequencies (11.7Ghz and above). In your sat menu you should be able to set the LNB for Auto Tone and 9.75Ghz/10.6Ghz