help with a fault

geoyou

Member
Hi all, bit of a long story so I will try and be brief.

Box A (SKY HD) in main living room has for some time been getting "your box isn't getting a satellite signal" message. I checked back of box and yes both of the cables were shonky. They needed reterminated correctly. Thought that was all that was wrong. A few days later the issue emerged.

Called the aerial guy out (to move my terrestrial aerial) and got him to reterminate the rear connectors and I noticed that one of the connectors at the LMB needed redone.

He did and I thought that was that, job done. Nope two days later the message pops up again.

1. pulling hair out, swapped Box A with Box B (upstairs bedroom skyhd box). Fault remained downstairs, box a worked upstairs b box b now shows fault.
2. keeping boxes where they were, swapped LMB ports 1 and 2 with ports 3 and 4 and vice versa.
3. fault remained box A or B downstairs. The only common point being the cable that runs for LMB (now position 3 and 4) and into the box directly.
4. Services menu, signal indicator has intermittently now shown input a NO SIGNAL, input b no signal, BOTH no signal and both normal.

I believe I have proved, its not the sky hd box, its not the LMB so it looks like this is a cable fault.

I have a detached house its unlikely that someone has cut the cable, could there somehow be water ingress that sometimes shorts the cable out?

Would a break/short due to corrosion say of the main conductor in say cable A cause BOTH channels to show no signal?

I posted on the Samsung forum thinking with my covid brain that it might even be an issue with one connect, but I think we can safely discount that theory the shotgun cable goes direct from LMB to my downstairs sky hd box, and the second feed (for completeness) goes to the upstairs SkyTV box.
 

logiciel

Moderator
It’s LNB.:)
 

leasty

Standard Member
I agree with Logiciel - it's more likely to be the LNB. How old is the it? They are exposed to the extremes of the elements and don't last forever. Intermittent faults are not uncommon in old LNBs especially when there are extremes of temperature - cold/frost overnight and bright sun during the day. I would have expected the aerial guy would have noticed if the cable was in poor condition - potentially another job for him! Get your aerial guy back if he does LNBs, if not call Sky or an independent.
 

geoyou

Member
Thanks All, I will pre-empt the possibility of the aerial guy arriving, saying its the LMB and the response "I don't do those, you will need to contact... "

Thanks all, the thing that made me think it was NOT the LMB is that ports 1 and 2 were originally connected to downstairs and on swapping over to ports 3 and 4 the fault did not move to with the ports.

Logically if ports 1 and 2 were duff then surely connecting the upstairs tv to ports 1 and 2 I would have seen the fault move to the upstairs bedroom?

The LMB isn't that old really maybe 5-6 years (when we got the multibox connected).

So its cable (unlikely unless water ingress somehow has screwed with it) or the LMB... its not exactly rocket surgery really but thank you for focussing my thoughts.
 

logiciel

Moderator
It’s still an LNB!:)
 

geoyou

Member
Sorry to drag this out, but is it likely that an LNB fault would give symptoms like this?
Quad core: feed 1,2 to downstairs, feed 3,4 to upstairs. NO ISSUES upstairs at all noted, although it isn't used that often.

1, downstairs intermittent no signal on input 1.
2. downstairs intermittent no signal on input 2.
3, downstairs intermittent total loss of service on 1 and 2.
4, upstairs no issues noted.
5, I have swapped LNB pairs 1 and 2 with 3 and 4. No change in symptoms.

It can go several hours operating correctly then one of the above conditions will appear.
 

geoyou

Member
Just for the sake of completeness. The LNB was replaced. Terminal 2 looked dark at the core, looked like there had been arcing or water ingress.

Aerial guy arrived late unfortunately and it was dark, so he reterminated connections at the rear of the sky HD box and at the LNB and as above replaced the LNB itself.

Any further issues and we will replace out the whole length of the shotgun cable. All good for now, thanks to all for your help.
 

The latest video from AVForums

Podcast: LG C1 OLED First Thoughts + JBL Synthesis SDR-35 Review, TV Show & Disc Reviews & more
Subscribe to our YouTube channel
Support AVForums with Patreon

Top Bottom