LNB Weather Protection

[Vipersan]

A very interesting thread ...

Just out of curiosity ...has anyone tried a dedicated water repellant spray ?

The type of thing used on shoes ...or tents ...
I know this stuff is designed more for fabrics ...but would it perhaps work on the plasic caps of lnbs or even dish faces .

rgds
VS

 

[sonnetpete]

Yes, I wondered about rainx as an alternate. It's that stuff you use on helmet visors to repell rain. Don't know how long it might be effective before needing another spray and looking it up online it's a tad expensive.

 

[AlphaOm]

Thanks for this most interesting analysis, St1.

Considering the signal quality I have with Thor 6 on a 1m Orbital dish - about 50% on a sunny day, which I'm already surprised at considering I'm out of the official footprint - there's no doubt that a 120cm dish would provide me with a much better rain fade margin. But since I can't do much about the dish size for now, I am keen to try anything that can help me to preserve as much of the signal as I can in poor weather.

I've already got the best or biggest dish I can get, it's perfectly aligned, and my lnb is a Black Ultra. Can't do much more there, I don't think. I'll try the layer of furniture polish or any other water repellent soon, but I also want to get some rain cover for my lnb (whether I buy one or I use a plastic bottle). The only thing stopping me for the time being is the worry that they would or could make the lnb arm shake unreasonably when it gets windy - which does not do wonders for the signal, as we all know. Or I'd have to reinforce and stabilise the lnb arm somehow, too.

Looks like I'm going to spend more time on the ladder than on the sofa!!! But then again, isn't that the main idea of this hobby anyway?!?

 

[AlphaOm]

Update:
Quite impressed with the results provided in poor weather by the cut plastic bottle that I'd attached to my LNB (thanks AnalogueSat!), I decided to try to improve the aesthetics of the LNB umbrella and bought one of those I saw on the internet. It was delivered in a big, flat box and is made of quality plastic parts, as well as bolts and nuts, of course (still overpriced for what it is, though). Once assembled, the item itself is quite bulky but lighter than you'd expect. It's visibly designed to accomodate two LNBs on a multibracket. It was very easy to attach to the LNB arm and I was surprised to find out that I did not even have to adjust the elevation of the dish - the LNB umbrella visibly does not weigh enough to lower the LNB arm at all. Once fitted, I was quite happy to see that it is far less obtrusive that I'd imagined it would be. We had some heavy rain yesterday, so it was ideal to check how the umbrella behaved, and I have to say that I'm quite impressed. I did lose about 3 to 5% of signal quality, as you would expect in bad weather, but that was nothing compared with the 10 to 12% that usually disappear in similar weather. The LNB cap remained perfectly dry, and my signal stable.
So far, it is behaving really well in moderate wind and does not appear to make the LNB arm wobbly or shaky. Of course, I will have to wait for those severe gales to find out whether that umbrella will turn the LNB arm of my Orbital into a kite or not. If it ends up in Terryl's garden then we'll know for sure it's not a item to be used!

It also remains to be seen how the see-through plastic the cover is made of will behave over time. I'll be impressed if it doesn't yellow or splits within the next few years (hopefully not before that...). I'll keep you posted, of course, but so far it has done wonders for the stability of my temperamental signal from Thor 6 in the rain. Well, pretty much the same as the plastic bottle - just looks a bit nicer according to the wife : )

 

[Terryl]

Not a bad looking piece of hardware, but watch out if you have big snow and ice problems, it may build up on top of that and cause the dish to sag, an inch of ice on that could would weigh about 5 pounds, so keep an eye on it this winter.

 

[Lazarus]

Enterprising!

 

[AlphaOm]

Thanks for the advice, Terryl. What you say makes a lot of sense - as always. I'll keep an eye on it, and will remove it if we get the same kind of winter as last December (here in the UK, I mean). Fortunately, attaching it to the arm and removing it takes about 90 seconds. Takes longer to get the ladder and climb it!

 

[archive10]

Man, this summer sure is one of the wetter ones...

After wiping the LNB a couple of times, I decided to check analoguesat's advice, and created my own rain cover. Inspired by timo_w2s thread elsewhere, I put fashioned one out of a plastic pint glass. (Plastic glass??)

It does makes things much better, especially with light rain, but not ideal. The glass (plastic?) tends to blow off if there's a lot of wind, and that's not unusual here in Denmark, and even if it stays on, you still get droplets sticking to the plastic (glass?) even though it's almost vertical.

As a twist on the discussion earlier in the thread, I'm going to try waxing and polishing the front of the (oh I give up) glass, to see if the drop will slide off easier. Results report to follow...

(Still the like proper cover, I'm tempted to get one myself).

 

[archive10]

Also, while contemplating timo_w2s's discussion of his 1.8m dish in Finland, it occurred to me that the prime focus dishes do have an advantage here, since the LN is actually pointing downwards. This means that at least rain doesn't fall straight onto the LNB cover. If you stick one of those little caps (satellitesuperstore seems to be jolly pleased with their design) on the LNB, you can even protect it from wildlife. and with a small perspex cuff, you may even avoid anything flowing down at all over the surface of the feedhorn. As the cuff would only obscure a small part of the incoming signal, less signal loss would result.

What's more, we could get the same effect mounting the dish upside down (like some people seem to do in the middle east). This would mean that the LNB would be pointing somewhat downwards, achieving the same thing, but no signal shadowing. Of course snow on the dish could be more of a problem, as would bird droppings etc...

 

[timo_w2s]

Also, while contemplating timo_w2s's discussion of his 1.8m dish in Finland, it occurred to me that the prime focus dishes do have an advantage here, since the LN is actually pointing downwards. This means that at least rain doesn't fall straight onto the LNB cover. If you stick one of those little caps (satellitesuperstore seems to be jolly pleased with their design) on the LNB, you can even protect it from wildlife. and with a small perspex cuff, you may even avoid anything flowing down at all over the surface of the feedhorn. As the cuff would only obscure a small part of the incoming signal, less signal loss would result.

I don't think satellitesuperstore sell those little caps on their own though? Wouldn't want to change my feedhorn as it's matched to the dish. Also, what are the chances the plastic is enough to kill the Astra 2D signals? ;)

 

[martinuk]

On fringe satellites (such as Nilesat) raindrops on the LNB cap can definitely degrade your reception. In my experience it can knock your SNR down by 5 or 6 percentage points. I have no doubt that rain on the dish will have it's affect too but it seems less able to adhere to the dish surface.

I don't have an LNB cover, though I have seen a couple of designs for sale. I tend to use a 'Vileda' extendable floor mop to remove excess overnight rain on the LNB cap when it's good reception conditions the next morning. Other than that I just put up with it if it's raining!!

Edit : I think this is the sort of thing you've seen

_http://www.amazon.fr/Indipc-SAT-PARAPROT-Protection-pour-LNB/dp/B000R3P2YE/ref=sr_1_1?ie=UTF8&qid=1309332944&sr=8-1

hi ive got cover for lnb on my channel master but got no lid goes over feed horn end rain cover know were can get one from

 

[Terryl]

I don't think satellitesuperstore sell those little caps on their own though? Wouldn't want to change my feedhorn as it's matched to the dish. Also, what are the chances the plastic is enough to kill the Astra 2D signals? ;)

Any clear plastic will do, but be sure it's not one that will block IR or UV (like some window films) as that has a mico-thin coating of metal and would attenuate the signal.

Also any plastic that is black or very dark in color as that might have carbon in it, that would block the signal also.

 

[Terryl]

hi ive got cover for lnb on my channel master but got no lid goes over feed horn end rain cover know were can get one from

Saran wrap with a rubber band will keep things dry till you get a proper one.

 

[AlphaOm]

Sorry to revive my old thread but I thought I'd let everyone know that the rain cover I fitted over my lnb a few months ago behaved surprisingly well in the amazingly strong gales that hit the country a few weeks ago. It didn't move at all, and never made the lnb arm wobble like mad - which always was my main concern. I've found it to be a very good piece of hardware so far, and overall has allowed me to retain a relatively stable signal quality level, regardless of the weather.

 

[Robinson74]

And here is my do-it-yourself cover.

 

[Terryl]

Those 1 or 2 liter clear plastic soda bottles make good covers, and last a long time, I have one sitting out on the back fence, it's been there for ten years, it has not cracked or aged yellow at all, it does have a few bullet holes in it (a good 100 yard target) but would make a good cover if cut right.

 

[Captain Jack]

They always do say that after everything on this rock is dead after billions of years, the only thing that will remain is plastic that never degrades....

 

[Terryl]

I can see some alien archeologist 3 billion years from now, digging through a Hollywood graveyard and finding nothing but Boob implants, it thinking that these are eggs for the future race, then trying to hatch one.


Oppps sorry one too many beers, it getting hot today.

 

[daro2096]

Sorry to revive an old thread. Are those heating things that go on the back of satellite dishes worth the time and effort for UK locations? They are the ones that heat your dish up and melt the snow that has covered it.

 

[Terryl]

Well I'm not in the UK but I have installed several dishes that were heated in the Lake Tahoe area, they keep the ice buildup to a minimum, they also sell heated LNB's.

A cheaper way is to use a good high quality black lawn/leaf bag big enough to fit over the dish and be closed up at the bottom, this will help shed the snow, anther thing to add to this is a low wattage drop light, you put the drop light inside the bag out of the way of the LNB.

Also I used an external rated thermostat rated to handle the AC power and wattage needed to run the drop light.

A plumbing supply house may also have pipe heating tap, these tapes may also have a thermostat as part of the setup, it will come on below freezing and go off above freezing.

Pipe heating tape....https://www.amazon.co.uk/Easy-Heat-AHB-130-Heating-Cable/dp/B0000DGAJS