Ariva 150 combo problem with combiners

snaps

Just dusted off my 150 combo, strange problem. only one cable feeding it so using combiners. Problem is when ive been watching satellite the terrestrial then doesnt work unless i power the lnb power on/off or reboot.

Checked for short circuits but all seem ok, any thoughts on this? Faulty combiner/splitter perhaps?

Tony

I've seem this once or twice and it was the lnb at fault. It seemed to be sending a harmonic into the UHF band distorting the saorview signal.

snaps wrote: »

Just dusted off my 150 combo, strange problem. only one cable feeding it so using combiners. Problem is when ive been watching satellite the terrestrial then doesnt work unless i power the lnb power on/off or reboot.

Checked for short circuits but all seem ok, any thoughts on this? Faulty combiner/splitter perhaps?

snaps

Tony wrote: »

I've seem this once or twice and it was the lnb at fault. It seemed to be sending a harmonic into the UHF band distorting the saorview signal.

I'm using a diseqc switch too (5, 13, 19, 28east). I've found if I switch to sky news before I switch back to UHF its OK.
It doesn't matter but I'm using emitel dvbt in poland. Channels 34, 36, 43.

Tony

Is sky news vertical polarisation ?

snaps wrote: »

I'm using a diseqc switch too (5, 13, 19, 28east). I've found if I switch to sky news before I switch back to UHF its OK.
It doesn't matter but I'm using emitel dvbt in poland. Channels 34, 36, 43.

snaps

Tony wrote: »

Is sky news vertical polarisation ?

Yes 12.207 v on 28east

Tony

Ok could be the LNB has an intermittent fault when 18v is supplied when you switch to HOR sat channel . Try selecting another vert channel and see if it has the same effect as sky news.

snaps wrote: »

Yes 12.207 v on 28east

Morning Wine

I would have suggested switching between low band & high band channels to see if it made any difference, though I couldn't link this with how the LNB power cycling mentioned in the OP seemed to fix the problem.

I can't see how it would be anything to do with switching polarity.

Tony

It is if it affects the LNB

Morning Wine wrote: »

It certainly isn't anything to do with switching polarity.

Tony

Another idea, try disconnecting the 28 LNB and see if the problem still occurs when you select one of the other satellite positions. If its ok then re connect the 28 lnb on its own without the diseq c switch using a double female f connector ,if the problem re occurs its almost certainly that lnb.

Morning Wine

Tony wrote: »

Morning Wine wrote: »

I can't see how it would be anything to do with switching polarity.

It is if it affects the LNB

Wouldn't any RF interference be generated by the LNB's local oscillators/mixers, & differences observed with different satellite channels selected, you would think would be due to the high or low band oscillators coming into play?

I don't see how switching between H or V aerial probes would have this effect.

Tony

From past experience and going on what Snaps has observed it seems the fault only shows up when 18v is applied to the lnb which is why I think it works ok on lower voltage vertical polarization.

Morning Wine wrote: »

I don't see how switching between H or V aerial probes would have this effect.

Morning Wine

It's not necessarily a fault with the LNB, probably just the combiner isn't good enough at filtering out the "normal" levels of noise the LNB puts out in the UHF TV band, though I believe LNBs vary in this respect.

Tony

If the combiner was faulty then its most likely it would not work at all. Lets wait to see what the OP finds out from trying the suggestions made earlier.

Morning Wine wrote: »

It's not necessarily a fault with the LNB, probably just the combiner isn't good enough at filtering out the "normal" levels of noise the LNB puts out in the UHF TV band, though I believe LNBs vary in this respect.

snaps

Haven't been able to play with TV so far today, its a washout here, kids been watching TV all afternoon. I'll have a look and a potter around when they've gone to bed.

snaps

I haven't had that problem now since, i will see if it returns. Ive left the last channel on various satellite channels (From 5, 13, 19,28 east), both V & H and all seems ok so far???

Tony

Talking about a problem always helps

snaps wrote: »

I haven't had that problem now since, i will see if it returns. Ive left the last channel on various satellite channels (From 5, 13, 19,28 east), both V & H and all seems ok so far???