3 lnbs,1 dish, diseqc,transponder confusion

**leecovuk** · 05-03-2005

hello everyone,

I have upgraded my sky minidish system using an ADT PIXX 3500 receiver and an exisiting Panasonic sky digibox.
The installer has used a monoblock lnb and another lnb on a 90cm eliptical dish. I _assume_ they are universal lnb's. The receiver is using diseqc to switch the feed externally down to one coax cable. I have set up Astra, Astra 2 and Hotbird on 3 different antenna ports in the receiver.

I am experiencing various troubles and confusion which presumably may be related:

1) The transponder arrangement and frequencies shown by the PIXX after channel scanning are out of step / wrong with respect to what is shown on frequency/transponder charts such as those on lyngsat.

2) I don't seem to be receiving all the signals I originally was when just working with my sky minidish setup. For example, I currently can't see E4 or Sky News anywhere in the PIXX's channel findings.

3) My plan to use loopthrough to the digibox for sky viewing is not working, because the digibox is saying 'no default trasnponder set' or 'no signal found'. This is after selecting a 'sky' channel on the PIXX and putting it into standby.

So, am I right in thinking the alignment of the new lnb install is probably wrong on the Astra 28.2E satellite?
How can I check/manually force the PIXX to try to tune correctly to all the transponders available?
What about Eurobird? Do those channels 'just get included' through the Astra 28.2E scanning?

I have tried my best to read up on all this, but I am further confused by the various voltage settings and other options in the PIXX and digibox 'hidden' installer menus. I just fail to understand them and how they may be central to my problems.

Please share any help or experience you can here, if you think 'ah I think I see what's going on'. If I'm sure I need to, I'll complain to the installer and get him back out.

Many thanks ..... help .... ! ....

lee

**rolfw** · 05-03-2005

I have not heard of many successful setups using a receiver with loopthrough, DiseqC switch and Sky digibox. You need to make sure that the 28.2 LNB is cabled to the A port on the DiseqC switch, as putting the receiver into standby probably relinguishes control of the switch and the switch will default to port A.

**leecovuk** · 05-03-2005

thanks Rolf,

What concerns me as well, is the issue that the PIXX isn't showing (receiving?) all of the Sky package channels. Presumably it should, even though it won't be able to view them?
This makes me suspect that the (monoblock) lnb hasn't been aligned properly, meaning certain needed frequencies aren't being received. However, the signal strength on all received transponders seems good to very good.

**rolfw** · 05-03-2005

Just looked at the setup again, are you saying that there is a 2 way switch and then a monoblock?

It would not be unusual for the receiver transponder list to be missing certain transponders, you may need to add them manually. Is there any reason why you want the Sky channels on the PIXX, a better solution would be to have a dedicated feed to the digibox and let the Pixx deal with the other two sats.

**leecovuk** · 05-03-2005

hello again rolf,

The switch is a 3 way switch; 3 lnb feeds in total which the installer told me to tune to ports a, b and c on the pixx.

The plan was to do the switching externally on a diseqc switch and keep just the one coax run.

**rolfw** · 05-03-2005

As far as I have experienced, monobloc LNBs have a built in 2 Way switch, I am a little confused by your explanation of the setup, can you supply pictures?

**leecovuk** · 05-03-2005

I didn't realise that; I was assuming based on how I understood things. Sorry, don't have any pictures.
All I really know about the outdoors set up, is that I was told to set up for 3 different ports in the pixx. I can see physically that the installer has used a monoblock and 1 further lnb.

I am currently doing a factory reset and rejig of the ports, just in case I got A and B reversed.

**leecovuk** · 05-03-2005

hmm

I was vaguely concerned about the issue that the receiver might either be faulty or in need of a software upgrade.
For eg, during and after the initial channel search, it shows sky channels under the hotbird menu along with many actual hotbird channels. The initial search on one of the astra ports also finds almost nothing, until I later do a further manual search.

The way this receiver works, is it has predefined satellite 'names' which I am associating onto 3 'antennas' using ports a, b and c. Am I right in thinking that the 'names' I choose really make no difference? (although I am trying to stick to a logic of astra, astra2 and hotbird)

Presumably the satellite v port issue is only a problem if the receiver causes a default to A when in standby, regarding the loopthrough problem you mentioned may be happening.

What I really need to do I suppose is somehow guarantee the external switch outputs are wired so that the sky astra ('astra2' presumably) is definitely destined for port A; if it is, presumably I should be able to select an astra2 channel on the pixx and then get a successful digibox performance by plugging the incoming coax directly into the digibox?

What I'm trying to do here is determine whether I or the receiver are at fault / wrongly set, before I contact the installer to check his external work.

**rolfw** · 05-03-2005

To test which sat is set on which port, you can do a manual search on a single transponder for each port. Pick a good transponder for Each sat on www.lyngsat.com, one with several unique channels and then search that transponder, if it finds the right channel, then you have the correct port and satellite allocation.

If Astra 28.2 is cabled to port A, then you should simply be able to plug the coax straight into the digibox and it should work, have you tried this?

PS. The receiver allocated satellite names should also include a transponder list pertaining to that satellite, so best to use them, even if they are incomplete.

**leecovuk** · 05-03-2005

thanks again;

yes, part of the reason why I suspect that some transponders are not being received is that when I select a sky channel on the pixx to select the right port, I still fail to get a signal reponse on the digibox when then directly plugging into it. It says 'no default transponder found' or 'no signal'.

What you say about the satellite names and transponder list is interesting; I thought the transponders shown by the pixx would be what it actually received, however the frequencies and respective transponders bear little or no similarity to that shown on lyngsat.
When I try to change a transponder to as shown in lyngsat, I get 'no channels found' when searching.

Does this suggest my PIXX software is out of date? Possibly causing all my problems?

Also, if most of the transponders I seem to be receiving have good or very good signal strength, does this rule out that the monoblock may be subtly misaligned? I don't know if a slight misalignment can totally knock out some transponders whilst others are fine.
I am using a 90cm elyptical dish.

**leecovuk** · 05-03-2005

just to add, the installer has confirmed that the 28.2 astra is destined for port B. He says the switch should not default to A when the pixx is in standby.

However, when I ask him if he's totally sure and maybe my monoblock has been misaligned, he currently goes quiet.

**rolfw** · 05-03-2005

Have you tried with the digibox connected direct to the input?

If you take the Pixx out of the loop, use the add channels function on the digibox and type in the information below, see which satellite it finds.

10,773 H 22,000 5/6 Astra 28.2E Channels found should be BBCs

11,597 V 22,000 5/6 Astra 19.2E Channels found should be DW TV, Sky News International etc

11,034 V 27,500 3/4 Hotbird 13E Channels found should be The God Channel, CCTV9 etc.

I am still at a loss as to how your system is set up, if it has a monobloc LNB, this has one output with an internal 2 Way DiseqC switch, you then need to switch between the single and MonoblocLNB which would require a 2 Way switch and complex DiseqC commands to use secondary commands to switch between monobloc outputs. By nature of the available monobloc LNBs, the monobloc should be set to 13 and 19 East, so would be B and C.

Unless a second cable run is impossible, you really would be better off with a separate cable run direct to the digibox, perhaps even with a twin LNb to feed the Pixx as well.

**leecovuk** · 05-03-2005

thanks again rolf;

Yes, I was wrong / forgot which satellites a monoblock is designed to get. I've been confusing myself here as I increasingly lose the will to live.
Therefore the single lnb must be for astra 28.2. The installer has however confirmed I should be using Port B for 28.2.
I have the other astra on port A and hotbird on port C.

I am currently checking with the installer whether he used 3 new universal lnb's. I believe my old minidish lnb will not work on my new dish; is that right?

I also see what you're saying about the switching involved; however, it does seem to be working successfully for all 3 satellites in the pixx.

I will now try the digibox channel searches you mentioned.

It still concerns me that my pixx may be out of date, regarding the 'fictitious' transponders and frequencies it shows.
I'm looking around for a possible upgrade, but I'm currently caught in a trap here generally, between doubting myself, the installer and the receiver.

**rolfw** · 05-03-2005

Don't be too concerned about the Pixx updates, they are probably available and the links are probably in our receiver Software section.

Don't know your viewing habits, but if you are used to recording channels from your Sky digibox, then everytime you switch on the Pixx, it will disrupt the recording to the digibox.

I will see if I can dig out a DiseqC switch tomorrow and have a play to see if it always goes to default when the receiver is in standby, if it does, then your setup will always be problematic.

**leecovuk** · 05-03-2005

thanks again - I do appreciate your support here.
I hope shortly I get / find a flash of inspiration one way or another.

btw I always knew my type of install would be restrictive, but the plan is to use the non-sky satellites as a casual option from time to time, rather than routinely wanting fully functional access to 2 or 3 feeds at once.
I just didn't expect my planning to result in not being able to use my digibox since thursday !

Can I possibly split the coax input locally near the receiver(s) and send one feed to both boxes? If I could, this however wouldn't have any further use than the loopthrough concept anyway, would it? ie i would have to use the pixx to detect astra 28.2 initially anyway.

**rolfw** · 05-03-2005

You could use an AB switch to connect both units, but whether that would solve the DiseqC problem, I don't know. I'm still pretty convinced that the 28.2 LNB needs to be on output A.

**leecovuk** · 05-03-2005

a little progress here maybe ...

I selected a sky channel from astra2 (CNN) on the pixx and then, having plugged the coax directly into the digibox, I can see a very strong signal strength and quality reading on the digibox display with the 10,773 frequency.
However, a search then is fruitless due to 'no default transponder found'.
I tried setting the suggested 10,773 as the default transponder with the settings shown earlier, but same problem.

So, does the signal strength and quality suggest that the switch is indeed still offering the wanted port B when the pixx is in standby / bypassed after selecting a port B channel? It seems so to me ? ....

The issue now seems to be setting the default transponder for the digibox. Any ideas why this apparently needs to change and what to?

Many thanks, as I get a little closer here.

**leecovuk** · 05-03-2005

just to clarify;

when i set the 10,773 as the digibox default transponder, the channel search goes on forever and doesn't seem to stop.

When I use the digibox default settings for default transponder, I get 'no default transponder found'.

Searching on the apparently strong 10,773 frequency gives 'no channels found'.

The digibox lnb settings are currently as per default as well, but I don't understand what impact they may have.

**rolfw** · 05-03-2005

I think that probably confirms what i am saying, if you do a search for other channels on the digibox using that frequency, it will probably come up with a data channel TDSL, that is on Astra 1, so the switch is defaulting to A.

PS. Don't change the default transponder from the one already set, use the find other channels option and search with that frequency.

**leecovuk** · 05-03-2005

I see; I will look into trying for the other satellites too.

Strange turn of events just now though;

coax back into pixx, loopthrough to digibox;
pixx kept turned _on_;
successful digibox install with default settings, but about half of the channels I usually receive are just blue screens;
when pixx goes into standby all channels go to blue screens with 'no satellite signal is being received'.

So this probably suggests a mixture of:
wrong 28.2 lnb alignment;
the port a/b issue

??

**rolfw** · 05-03-2005

If the Pixx is controlling the LNB, then it will be locked in either Horizontal or Vertical state, so you will lose a lot of channels on the Sky digibox. I hate to sound like a cracked record, but port A needs to be 28.2E.

Did you search for other channels on 10,733 on the digibox?

**leecovuk** · 05-03-2005

ok; sounds like i need to convince the installer to peel away his waterproofing and change the ports as you say. Presumably the lnb alignment may well be otherwise fine?

Yes did the search on that frequency before, but haven't done it again yet; must try to rush off to tesco.

btw I didn't expect the loopthrough to work at all when the pixx is active, but apparently some/all receivers allow loopthrough when on?

**leecovuk** · 05-03-2005

btw a temporary fix for me is probably to find a sky channel on the pixx which has the opposite polarity, so I can watch the missing digibox channels? This would presumably also rule out the lnb misalignment possibility.

**rolfw** · 05-03-2005

Yes correct.

List of FTA channels here http://www.lyngsat.com/28east.html

**leecovuk** · 05-03-2005

many thanks, rolf.
I will ask the installer to come and change those ports.
I doubt he will complain but I always expect the worst.

You see, it's things like the horizontal/vertical polarity causing lack of channels that I would probably never have worked out;
things like that and potentionaly more complex issues just leave me lost when it comes to lnb's etc. I haven't even managed to understand what the switching does or how an lnb works. eg the high and low frequencies ? ...

anyway, maybe it'll make sense one day although i have tried to read up myself.
I never learn well though unless i have someone to ask and put it into context for me.

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3 lnbs,1 dish, diseqc,transponder confusion Information exchange on LNBs, Single satellite, motorised and multi-satellite systems. DiSEqC switches, positioners, motors, actuators, dish-alignment etc.