Quad LNB

[RogerP]

Hi, I guess there's a fault with it, but since changing the LNB to a quad to connect a second box, everytime it starts to rain I lose channels, BBC goes first I've checked the dish alignment and it's fine. The strange thing is although the local BBC 1 goes (101) other areas are still OK. It's a Phillips LNB on a zone 2 minidish in Hertfordshire. Thanks for any ideas before I put my hand in my pocket.

 

[PoloMint]

Did you install the quad yourself?

Quad LNBs are heavier than single ones, it could be that the extra weight of the LNB is pulling down on the LNB, make sure that the arm is secure and at the right angle (sometimes easier said than done).

Do you loose the channels on both boxes?

 

[RogerP]

How do you know if it's at the right angle, I replaced the plastic push in clip with a screw and nut where it goes into the arm as there was a slight movement, and it's all snug now. When it's losing channels the on screen signal test doesn't change, around 90-100 strength, 60-70 quality, which, I think was higher with the single. Of course I havn't tried the obvious of checking the box in the boy's bedroom, but I have moved the cable to different outputs. The main box is a Grundig, which I saw on another post there may be a software problem with.Thanks.

 

[rolfw]

You need to go into the manual tuning menu, pick up the frequency of the missing channels and set that, the FEC and the symbol rate, then press search. The Digibox will then give you the signal strength and quality of the transponder with bad rception.

Sounds very much like the dish needs tweaking and probably the skew of the LNB as well, when looking at the dish from behind the LNB, it should be rotated to around 7 O'clock.

 

[RogerP]

Thanks, I'll get the steps out again and have another go with my trusty signal strength meter. Is a quad more critical than a single, I've not had any trouble before. I tried turning the skew before but it was difficult to tell any real difference unless I really turned it round a lot. It's about in the middle of the scale at the moment I think.
Regards.

 

[rolfw]

If the dish were perfectly vertical then you could set the skew exactly, but it probably isn't, so it really is a case of trial and error.

PS. a quad shouldn't be any more critical.

 

[j.m.]

I shifted from a Thomson Single LNB to a Cambridge Quad.... The Dish Nose dived & to be honest this Cambridge unit isn't a patch on my Sooper Thomson one O-st ............. Sad but true...... I found swearing at it & throwing the remote around helped a little O-Ha

 

[rolfw]

Those little Thompson LNBs are excellent allmost 10% better signal strength than the other minidish LNBs.

 

[j.m.]

Do the do a Quad version thet you know of ?

 

[rolfw]

Haven't seen one.