dual lnb

[alfred_1]

Re: dual lnb

Ok so if i use two single lnb's with an adjustable holder do i then need some sort of switch ?? and how does this set up work?

Yes you just need one Diseqcs Switch (which you can put behind the Dish)and you just feed port A & B from the the two Lnb's and connect a downlead cable from the Disecqs switch to the Receiver, alternatively you can use a Twin (also called Monoblock) Lnb with a six inch seperation angle for say Astra/Hotbird combination. You don't need a Diseqcs switch for this because its already provided in the Monoblock itself. Finally you have to configure your Receiver for this configuration.

[satfan]

Re: dual lnb

I have duo , but only hotbird work good eutelsat work terrible;/ In mono i don't have this problem

Re: dual lnb

Ofcourse with 2 lnb's the picture is only half as complicated.

To explain the picture to Steddie:

In the above picture you see a setup using 4 dishes each supporting 1 satellite, not 4 dishes supporting 4 satellites!! In your case you should think of the 'dishes' as an 'LNB on a bracket'.

The four gray 'blobs' represent the four 'receptors' in one single quatro LNB's. So in your situation the 'dishes' are to be interpreted as one single Quattro-LNB.

Each quatro LNB is connected to a 4-to-1 switch and each 4-to-1 switch then is connected to a Diseqc 1.1 switch. You would need one Disec1.1 switch for each receiver you wish to connect, or a more sophisticated distribution system, but that would be beyond the scope of this thread.

A quattro LNB is used because it offers a seperate output for each of the 4 'bands' that are used for commercial satellite TV in the KU band, (10600 to 11700MHz and 11700 to 12900MHz, both Horizontal and Vertical polarisation) If you would use a simple universal LNB, then you would be bound to one of the four bands by the 'primary' receiver. So if the primary receiver switches to a different transponder on another band, then a viewer on a secondary receiver would suddenly loose the signal.

Note: there are 2 types of quatro-LNBs, ones with integrated switches, which operate as 4 individual universal LNBs, and ones without switch, i.e. each output is limited to a single band. The first you can use on any system, the last you can only use in combination with a switch.

The setup presented may seem a bit complicated, but it allows any individual receiver to pick up whatever transponder from any of the selected satellites at any given time, regardless of what the other receivers are doing. Of course, if you go for 2 LNBs, you could do with half the picture. Also, you could use twin LNBs (yes, Twin, not Duo this time) instead of quattro, if you are happy not to connect more than 2 receivers. You would then run 2 quasi separate installations, instead of one universal one.

Note that if you go for the simplest of configurations, you will need as many 'receptors' per LNB as you want to connect receivers, but never more than 4, which would mean using quattro LNBs. As of 4 receivers you simply change the configuration. You might need another switch, but that's it.

I suggest you pass by the nearest satellite shop and explain the situation before ordering anything. There are many many options when it comes to switches, and some may stretch your budget quite far! It's nice to have a universal solution, like in the above picture, but if you are not running a hotel, that might not be exactly what you want. If you are looking for a simple household-situation, a sub-optimal solution is usually sufficient and less stressful for your bank-account.

Wow nice explanation, indeed the picture is a little to complicated and represents how you can use 16 LNB's with one reciver

But i think he can make an ideea about meaning of Diseq

[astr1d]

Re: dual lnb

Ofcourse with 2 lnb's the picture is only half as complicated.

To explain the picture to Steddie:

In the above picture you see a setup using 4 dishes each supporting 1 satellite, not 4 dishes supporting 4 satellites!! In your case you should think of the 'dishes' as an 'LNB on a bracket'.

The four gray 'blobs' represent the four 'receptors' in one single quatro LNB's. So in your situation the 'dishes' are to be interpreted as one single Quattro-LNB.

Each quatro LNB is connected to a 4-to-1 switch and each 4-to-1 switch then is connected to a Diseqc 1.1 switch. You would need one Disec1.1 switch for each receiver you wish to connect, or a more sophisticated distribution system, but that would be beyond the scope of this thread.

A quattro LNB is used because it offers a seperate output for each of the 4 'bands' that are used for commercial satellite TV in the KU band, (10600 to 11700MHz and 11700 to 12900MHz, both Horizontal and Vertical polarisation) If you would use a simple universal LNB, then you would be bound to one of the four bands by the 'primary' receiver. So if the primary receiver switches to a different transponder on another band, then a viewer on a secondary receiver would suddenly loose the signal.

Note: there are 2 types of quatro-LNBs, ones with integrated switches, which operate as 4 individual universal LNBs, and ones without switch, i.e. each output is limited to a single band. The first you can use on any system, the last you can only use in combination with a switch.

The setup presented may seem a bit complicated, but it allows any individual receiver to pick up whatever transponder from any of the selected satellites at any given time, regardless of what the other receivers are doing. Of course, if you go for 2 LNBs, you could do with half the picture. Also, you could use twin LNBs (yes, Twin, not Duo this time) instead of quattro, if you are happy not to connect more than 2 receivers. You would then run 2 quasi separate installations, instead of one universal one.

Note that if you go for the simplest of configurations, you will need as many 'receptors' per LNB as you want to connect receivers, but never more than 4, which would mean using quattro LNBs. As of 4 receivers you simply change the configuration. You might need another switch, but that's it.

I suggest you pass by the nearest satellite shop and explain the situation before ordering anything. There are many many options when it comes to switches, and some may stretch your budget quite far! It's nice to have a universal solution, like in the above picture, but if you are not running a hotel, that might not be exactly what you want. If you are looking for a simple household-situation, a sub-optimal solution is usually sufficient and less stressful for your bank-account.

Re: dual lnb

Ok so if i use two single lnb's with an adjustable holder do i then need some sort of switch ?? and how does this set up work?

Yes you do, look for Diseq Switch, looks something like this :

[peremacedonia]

Re: dual lnb

Near here the wind peaked at 172Km/h the other day...

it was storm before 2-3 weaks here and in te morning motor was ok,sat possition was ok but lnb was in my neighbor yard

[steddie2.5]

Re: dual lnb

No, only that if you have a duo LNB with the heads separated at 6 degrees, that decides the birds you can combine.

If you use a bracket like on the picture posted by yselim you can get satellites as far apart as your dish and bracket allows, but generally speaking 30 degrees would be the maximum, as the 'virtual size' of the dish has, by then, been reduced by a factor 2.

I think I explained it all in my reply to steddie2.5 in my first post in this thread. There is no general answer to this matter, all depends on where you are and what you want to get. The only 'universal' solution is a motorized dish.

@Conax, the effect you describe is caused by the fact that the extra LNBs are not used in the prime focus of the dish. On bigger dishes the angular positioning is of more importance than on smaller, where sometimes you might get a better response if you are slightly out of focus. However, if you put both LNBs out of the main focus, the angular distance should be independant of the dish size and only depend on the distance between de satellites and you geographical position.

All in all the difficulty of properly aligning a dish is proportional to the power of the number of LNBs mounted on the dish. If you have difficulty pointing a single bird, you should be aware that you will need to double your effort to get 2 birds from the same dish, and quadruple it to get 3.

Ok so if i use two single lnb's with an adjustable holder do i then need some sort of switch ?? and how does this set up work?

Re: dual lnb

Near here the wind peaked at 172Km/h the other day...

That is not wind that is quite a storm , anyway who will collapse the motor rotating the dish or the gauge between the dish and motor, i think if you got this issue you know exactly what happened

Re: dual lnb

Well, with my toroidal dish I use now 8 different LNBs for 9 satellites (position 9°E and 10°E work with a single LNB). But that's what toroidal dishes are for. Motors are not an option where I live because there are often very, very strong winds.

Do you know how strong it has to be to manage to disrupt a motor based system. Is first time i hear that a motor system can be disrupt by the wind.

The motor is not capable to turn the dish or the dish is moved when is in static position because of wind and motor grip system ?

[powerman]

Re: dual lnb

I think the motor have disaster if you use of dishes seperate is better

[astr1d]

Re: dual lnb

You are sayng that if you have between satellites more then 5 degrees it won't work using separated LNB's ?

No, only that if you have a duo LNB with the heads separated at 6 degrees, that decides the birds you can combine.

If you use a bracket like on the picture posted by yselim you can get satellites as far apart as your dish and bracket allows, but generally speaking 30 degrees would be the maximum, as the 'virtual size' of the dish has, by then, been reduced by a factor 2.

I think I explained it all in my reply to steddie2.5 in my first post in this thread. There is no general answer to this matter, all depends on where you are and what you want to get. The only 'universal' solution is a motorized dish.

@Conax, the effect you describe is caused by the fact that the extra LNBs are not used in the prime focus of the dish. On bigger dishes the angular positioning is of more importance than on smaller, where sometimes you might get a better response if you are slightly out of focus. However, if you put both LNBs out of the main focus, the angular distance should be independant of the dish size and only depend on the distance between de satellites and you geographical position.

All in all the difficulty of properly aligning a dish is proportional to the power of the number of LNBs mounted on the dish. If you have difficulty pointing a single bird, you should be aware that you will need to double your effort to get 2 birds from the same dish, and quadruple it to get 3.

[peremacedonia]

Re: dual lnb

being inexpensive musnt be the issue. there is an important difference betwen usage of motor and fixed lnbs. when you use two fixed lnbs you will not wait to switch to another satellite. on the other hand if you are using motor you have to wait antil motor rotates the dish right position. if you frequently switch between astra and hotbird or another satellite, it is better to use fixed lnbs rather than motor.

personaly I would prefer two dish .one with several fixed lnbs to watch my favourite satellites and another one with a motor to watch others.

and how many lnb's need to watch from 42e-30w?

Re: dual lnb

It also depends upon the dish size. For two different satellites, distance is less with a smaller dish and you have to increase the distance on a bigger dish to recieve the same satellites. That is something interesting.

Dish and also area were you are, the size of the dishes varies on diffrent zones of the globe

Re: dual lnb

Yes. A duo has a fixed separation between its heads and that decides which satellites you can combine. If you have one with 6 degrees, it would serve -say- Astra 1 (19E) and Hot Bird 13E, but it would be quite useless for Astra 2/Eurobird (28.2) because there is not much going on on either 34 or 22 degrees east. If you have one with 4 degrees, it helps out at Astra 1 (19.2E) and Astra 3 (23.2E) or Astra 2 (28.2) and Astra 3, or any other pair that is between 3.5and 4.5 degrees apart (closer to the horizon these numbers will be different.)

Best sites to look for these LNBs would be Ebay! Or ******

However if you want best flexibility, most channels and your geographical situation allows for it (free view from horizon to horizon) go for a rotor!

You are sayng that if you have between satellites more then 5 degrees it won't work using separated LNB's ?

[astr1d]

Re: dual lnb

Yes. A duo has a fixed separation between its heads and that decides which satellites you can combine. If you have one with 6 degrees, it would serve -say- Astra 1 (19E) and Hot Bird 13E, but it would be quite useless for Astra 2/Eurobird (28.2) because there is not much going on on either 34 or 22 degrees east. If you have one with 4 degrees, it helps out at Astra 1 (19.2E) and Astra 3 (23.2E) or Astra 2 (28.2) and Astra 3, or any other pair that is between 3.5and 4.5 degrees apart (closer to the horizon these numbers will be different.)

Best sites to look for these LNBs would be Ebay! Or ******

However if you want best flexibility, most channels and your geographical situation allows for it (free view from horizon to horizon) go for a rotor!