Advice Needed Loosing fringe reception

[Spiff]

Good evening Gentlemen.

I have had this happening for a while with 7 and 8 West.

These are both lower signals with me, but will drop in quality or disappear completely over a short time frame.

I have in the past used a soft brush into the horn as far as the plastic membrane across the LNB itself.

A spider sometimes came out and all was back up.

The last couple of times though no spider, I think condensation is forming on that membrane, as a quick turn with the brush and signals are up.

The Lnb is an Inverto white C120, it is new but the same happened with the single output one the twin has replaced.

I had noticed in the past when I fitted a cap to the horn, that if it got wet attenuation occurred, so I stopped using one.

But the problem now happens further in on the LMB membrane.

Has anyone else had this problem ?

God Bless Spiff

 

[Spiff]

I have tried various covers for the horn, Selotape being OK, but ended up with Clingfilm which appears to be a favourite for low loss.

Time will tell if it helps with condensation further in on the LNB membrane.

God Bless Spiff

 

[nelson_b]

Good evening Gentlemen.

I have had this happening for a while with 7 and 8 West.

These are both lower signals with me, but will drop in quality or disappear completely over a short time frame.

I have in the past used a soft brush into the horn as far as the plastic membrane across the LNB itself.

A spider sometimes came out and all was back up.

The last couple of times though no spider, I think condensation is forming on that membrane, as a quick turn with the brush and signals are up.

The Lnb is an Inverto white C120, it is new but the same happened with the single output one the twin has replaced.

I had noticed in the past when I fitted a cap to the horn, that if it got wet attenuation occurred, so I stopped using one.

But the problem now happens further in on the LMB membrane.

Has anyone else had this problem ?

God Bless Spiff

Hi
I,v removed the membrane on the l.n.b. as it tends to steam up (sometimes on the inside) and indeed - cause issues on weak signals ... i have instead relied on a good cover on the Feedhorn ... on my Channel master offset dishes in the past
On Prime focus - you just need something to keep the spiders out of the feed ... or just leave open and de - spider it now and again .. ;-)
Cheers.

 

[Spiff]

Good evening Nelson_b,

Thank you for your reply, I may well remove the membrane from the LNB and fit it to the feed horn instead, in such a way that it can be removed if it mists up there.

I have tried various bottle tops an so on, on the feed horn over the last couple of days, selotape and cling film gave the least attenuation.

Leaving it open in our location is not an option, we are 50 metres from the sea due West.

The salt air is very destructive, I left a C band LNB open for a year or two and it was badly corroded inside.

The Spiders just love the dishes : )

God Bless Spiff