Hallo everybody, after many years of smooth PROGDVB I decided to buy a dual lnb (hotbird + astra = one single exit) and the problems started. I read several posts on this subject, but I can´t really sort it out!

The problem: hotbird lnb is the primary. I set up Diseqc 1.0 or 2.0 in Progdvb (order being lnb 1 = hotbird, lnb2 = Astra).
I have 99% strength & 75 % quality for HB, but 0% & 0% for astra, except for 11538V, 22000 where I have 75% & 60%...
I tried all the possible config (mini diseqc, add switch...); no way.
The double lnb says Disecq 2.0 on its stamp.

I read that BSD drivers migth be the problem Vs the WDM drivers for Diseqc management, but
- how do I know what I am using as derivers (BSD or WDM)
- how do I know if the issue is coming from the drivers (see above)

Any help is highly appreciated. Thank you in advance

The drivers of a BDA device normally identify as such in Windows device manager.
A look into the .inf files of the driver installation source may also be quite informative.

However,for many devices with BDA drivers, you have to check device options in ProgDVB, to select a DiSEqC workaround.

BTW, you told to now have a "dual lnb" / "double LNB" now. Should be called Monoblock, normally.
One of the other names is for different hardware, the second one is not defined.
Let's stay precise, to not misunderstand each other.

Did you scan any stations on the one signal on your second position? Do those really come from Astra 19.2°E? Verify on satcodx.com

Hope, you did NOT mount the Monoblock upside down, nor on a dish with subreflector. Won't work then.

Hope, the distance between the feeds equals 6.2° on YOUR dish, exactly. Both size and focal distance (F/D) of the dish can make this fail.

Hope, you took care, to adjust the height of the second feed correctly, if you are not living at 16.1°E precisely. The LNB feed for the position with a higher elevation on location must be positioned a little lower than the other one.

Jürgen,
thank you for your post. You are right I have a Monoblock, sorry about that! I checked and I should have WDM drivers installed (DTVaudio.sys & DTVvideo.sys)
I scanned all positions on Astra, and after checking on satcodx.com I realized that in fact the only channels I find (about 12) in reality are on Hotbird 8... so no Astra 19.2
As far as concerning the installation upside down, I do not think so because the the cable is supposed to be on the lower side. The position of the astra LNB is left of the HB loking face to the dish. I have no idea what is a "dish with deflector" and could not find on google... so I cannot say.
The same for the 6,2° distance on my dish... cannot really say... any help on how tho check?
Finally, if I understand right, the astra feed (higher feed) should be lower than the HB feed. This can be checked as soon as the bad wether is gone... not nice to go on the roof with heavy rain
Your comments are appreciated

Let's get started from indoor, theory based...

Did you read the manual for the Monoblock carefully?
Does it tell, what bird would be first and what second position, for a Astra / Hotbird system?
If made for Germany, it's possible (but not necessarily so), Astra must be the first one on the DiSEqC. If so, you may be heading to Hotbird with the wrong feed.

Also possible, ProgDVB simply does not support DiSEqC for your device (yet). If using BDA drivers, enter device options in ProgDVB, to select and possibly find a working DiSEqC patch for BDA.
If using a WDM device, find supported features described in devise list, once your device in use is marked.


A Monoblock has a fixed distance between the feeds. This means, on a given dish type, it's made for just one dish diameter, normally either 60 or 90 cm diameter. A little smaller or bigger might still be OK, but if a Monoblock would do 6° distance fine on a 60cm, it would try to do just 3° on a 120 cm dish of the same type.
In addition, the offset angle has an influence on the resulting linear distance on multifeed systems.
Rules of geometry...

Relative height of the feeds may be important for fine adjusting, but things should in any case work with the thing being mounted strictly horizontal, to get started. Keep in mind, tilting the Monoblock to a side would also interfere with skew. And there's no skew (polarisation decoupling) adjust on a Monoblock.


Dish types are various.

Most are offset dishes, with the LNB arm below the center of the dish.
In earlier years, prime focus dishes were widely used, with the LNB placed exactly in front of the center of the dish. Those had a different focal distance (f/d), that required different feeds to be used. And those give different distances for multifeed.

Both dish types have just one reflector, by this reverting each direction. South turns into North for the LNB, up into down, left to right. And even a circular polarisation would revert.
Normal LNBs do know about this.

Some modern dishes use an extra sub reflector.
Like toroidal ones do.
On those, the LNB does not look onto the big reflector, but to the sub reflector, almost to the bird, like the dish itself.

Means, with a single reflector, the more eastern bird would have it's feed / LNB mounted west of the other one.
But on a dish with an extra sub reflector, the more eastern bird goes to a more eastern LNB.

Think semi-optical.
If in any doubt, use pen and paper, to visualize the compass rose, birds on the Clarke belt, reflector, LNBs and signal rays.

Please read all this very carefully.
If necessary, more than once.
Perhaps print this page.

I would not like the idea of having to repeat myself.