Is the solution a Quad LNB?

[clybber]

Hello,

I've currently got a PowerVu 9324 receiver hooked up to a dish with a single LNB for receiving AFN on Hotbird and 13degrees. The 9234 has a switch on the back called "LNB PWR" which I assume sends DC voltage to the LNB for power.

I would like to use this same dish to simultaneously receive the SKY italia package which I understand is also on Hotbird at 13degrees. I would like to get the MySKY HD package which includes a PVR to record. This system requires two RF runs from the dish. My understanding is that I will need a quad LNB. One run from the LNB will feed my 9324 with two others feeding the SKY decoder. My question is about the DC voltage. Does a SKY decoder also send DC up to the LNB. If both the SKY decoder and 9324 are sending DC to the quad LNB, is that a problem? Is a quad LNB really 4 logically seperate LNBs? Will this work?

thanks

 

[satelliteman]

Correct, think of a 'Quad' as four independent LNb's in one housing.
A Quad will give you four separate switched outputs and an Octo LNb will give eight

 

[clybber]

Perfect, thanks.

Could you point me to a piece of equipment that might let me run the 3 LNB outputs on one cable? A triplexor of some sort I guess.

 

[rolfw]

You can use a stacker/destacker for combining two cables, but they are quite expensive, cheaper in most cases to run the extra cables.

 

[clybber]

Cool, thanks. Agreed - a few cables is pretty inexpensive.

 

[eklektofonic]

Hello,

I've currently got a PowerVu 9324 receiver hooked up to a dish with a single LNB for receiving AFN on Hotbird and 13degrees. The 9234 has a switch on the back called "LNB PWR" which I assume sends DC voltage to the LNB for power.

I would like to use this same dish to simultaneously receive the SKY italia package which I understand is also on Hotbird at 13degrees. I would like to get the MySKY HD package which includes a PVR to record. This system requires two RF runs from the dish. My understanding is that I will need a quad LNB. One run from the LNB will feed my 9324 with two others feeding the SKY decoder. My question is about the DC voltage. Does a SKY decoder also send DC up to the LNB. If both the SKY decoder and 9324 are sending DC to the quad LNB, is that a problem? Is a quad LNB really 4 logically seperate LNBs? Will this work?

thanks

An aerial installation mate of mine suggested that the best solution is to install a good signal amplifier near to the dish with a single universal LNB and then configure all receivers downstairs to "LNB power = off".

 

[rolfw]

An aerial installation mate of mine suggested that the best solution is to install a good signal amplifier near to the dish with a single universal LNB and then configure all receivers downstairs to "LNB power = off".

Can't see that working, as there are four different bands on a Universal LNB and most of the receivers wouldn't work for most of the time.

 

[eklektofonic]

Can't see that working, as there are four different bands on a Universal LNB and most of the receivers wouldn't work for most of the time.

But the "IF amplifiers" on the market are designed to provide current for all 4 bands on the LNB, then surely it will work right?

 

[rolfw]

No, wrong, a single universal LNB offers one band at a time, horizontal low, horizontal high, vertical low, or vertical high, not all at the same time, so when different receivers tune to channels in different bands, the LNB can only provide one, hence the need for a quad output universal LNB.

 

[Analoguesat]

No - an lnb can have one of 4 states

horizontal / vertical polarity - switched by a 13/18V voltage on the cable

hi band / low band - switched by a 22khz tone on or off on the cable. Therefore if more than one receiver is connected to one lnb, then as soon as one receiver is sending the correct instructions to go 18V / tone on, then the lnb will switch to that band and nothing any of the others can do can bring the receiver out of that state. The other receivers would only have access to any channels on the same hi band / tone on condition.

Dont even think about trying to run multuiple receivers off one outlet of an lnb - all it will do is lead to confusion and intense annoyance if you want to watch a BBC programme and granny puts one of the shopping channels on in the other room - you immediately lose the BBC!

Edit drat - need to type faster!

 

[eklektofonic]

Many thanks for your advice rolfw and analoguesat, I will grill my mate on this...