Some twin tuner/diseqc questions/problems

[politby]

Greetings, sorry for writing in English - my German is not good enough for this subject.
I've had my 6000PVR now for a while with a single twin-LNB each connected to the Topfield's two tuner inputs via its own cable.

I've now installed a WaveFrontier T90 toroidal antenna with 4 twin LNBs, configured for Thor, Astra 1, Astra 2 and Sirius satellites. I have two Spaun 411WSG 4-way DiseqC switches, both connected this way:

Port 1 - Thor 1W LNB
Port 2 - Sirius 5E LNB
Port 3 - Astra 19E LNB
Port 4 - Astra 28E LNB

with outputs connected to the two respective tuner inputs on the Topfield.
I've configured the DiseqC settings in the Topfield LNB settings with DiseqC 1.0 enabled:

Thor: 1 of 4
Sirius: 2 of 4
Astra 1: 3 of 4
Astra 2: 4 of 4

I believe this is the correct setting?

The problem I have is that the signal quality indicator on the Topfield shows 99% for Thor, but stays at 0% for the other three satellites. I can still search for channels but I just find a small number of all the available transponders. This is identical for both tuners.

My installer says that the signal is very good for all four satellites when measured directly at the LNBs (before the Spaun switches). I also know that the cables are fine; no problems with the long switch-to-receiver cables because the Thor signal is excellent, and the switch-to-LNB cables (all 8 of them) are new.

Should I suspect a problem with the (brand new) LNBs, the switches, or should I find a new installer?

My geographical location is 59.29N 18.22E (just north of Stockholm) so I know Astra 2D reception is unlikely but Astra 1, Astra 2A/2B and Sirius should all be fine.

thanks in advance
P O Litby

[mvordeme]

Greetings P O,

welcome at the board and congratulations to your impressive new dish.

I believe that the problem is caused by the fact, that the twin LNBs as well as the Spaun switches use a DiSEqC 1.0 signal. If you switch to a channel on another satellite, the Toppy transmits the DiSEqC signal to the switch only once. The switch then switches the LNB, but the DiSEqC signal is not re-transmitted. Thus, the LNB is not properly configured. (Geek talk: DiSEqC 1.0 is not cascadable.)

As far as I can see (and I hope someone with more experience in this area will double-check), you will need DiSEqC 1.1 (or 2.1) switches (e.g. Spaun 420 WSG) instead of your current ones. You can then switch between LNBs using the DiSEqC 1.1 setting of the Toppy. Because the Toppy transmits the DiSEqC 1.1 signal first and then the DiSEqC 1.0 signal, the latter would reach the LNB and configure it correctly.

Maybe before you go off spending more money you should check that reception is working in principle by connecting your LNBs to port 1 in turn and running a channel search (with the appropriate LNB setting and network search enabled). And (just in case): You need to disconnect the Toppy from the mains before fiddling with the satellite installation. Otherwise, a short-circuit might destroy the tuner.

Regards,
-- mvordeme

[hgdo]

A twin LNB doesn't use DiSEqC.

[mvordeme]

So does this mean the setup should work with a DiSEqC 1.0 switch? Is the twin LNB switched by means of 14/18 V and 22 kHz and are these signals transmitted permanently? How can this be, if the 22 kHz signal is used for DiSEqC? Could there be a problem with the power supply for 4 twin LNBs from a single receiver?

So, instead of an answer there are four more questions, but I am confident that the answers will be found.

[politby]

[quote=""hgdo""]A twin LNB doesn't use DiSEqC.[/quote]

Now I'm completely confused. Are you saying that it's not possible to use switches when using twin (or quad) LNBs?

I believe my configuration is exactly like this one (same switches, even):

http://satlex.de/en/2participants-type_conf_2p_4s.html

except I don't have 2 separate receivers, rather 2 tuners in the same receiver. Why would this not work?

In any case, I have a good signal strength indication on all satellites - which I would think indicates the receiver has a good connection to each LNB. This would not be the case unless the switch configuration is OK, right?

/P-O Litby

[mvordeme]

[quote=""politby""]Are you saying that it's not possible to use switches when using twin (or quad) LNBs?[/quote]No. I think he is saying that - as opposed to what I presumed earlier - it should actually work. This leaves you with four possible causes of the problem.

1. There is something misconfigured in your LNB settings.
2. The Toppy cannot supply enough power for four LNBs.
3. The switches do not work. I think it is unlikely for both switches to be broken.
4. The LNBs do not work. I think it is unlikely for three LNBs to be broken.

I will have to look through the board for some answers. I know that there is a description, somewhere, but I was not able to find it, last night.

Sorry for the confusion,
-- mvordeme

[mvordeme]

Hi P-O,

unfortunately, I have not been able to find any helpful information. I even started my own thread in German in order to encourage people who lack the heart to answer in English. So far, I got no answers at all.

Currently, I think the most likely source of your problem is the lack of power from your Toppy. (Although the Toppy has two tuners, it only provides as much power as one single-tuner receiver.) Are all four LNBs of the same make and model?

Regards,
-- mvordeme

[Axel]

Hi, I would advise to first test each individual LNB without the use of the Diseq-switches.
Just connect the line from the LNB-otput directly to the line of the first tuner . In this case it is not needed to change the Diseq-settings in the Receiver. Leave them assigned as they are.
Do the search for the assigned satellite on the connected LNB.
Doing so has the advantage to only supply 1 LNB at a time.
Here you should get all stations with max. level and quality.
If not, there is something wrong with the adjustment of the LNB mounted in the dish.
If this work fine, you then can test with the Diseq-switch installed but always only one LNB connected to their assigned input in the switch.
This should also work. If not, you can first check with other diseq-settings 1 from 4 to 4 from 4
One of them should give you the signal from stations, you stored previously.

If it does not work, forget the switches and try with another make and model (I prefer Spaun swicthes)
If it does work with each LNB alone, test with 2 LNB and so on and check, how many LNBs work.

Do not start with the last advised test in reverse order, because for validation you need to know first, that all LNBs work fine on its own and the test, that the switch is OK, and also it is good to have the comlete working station-list before proceeding