Should I wrap up my LNB for the summer?

[joddle]

Sounds odd but actually I am serious. Every summer from late June to early Sept I return to the UK for about 10 weeks a) to have a holiday and b) to get away from the awfully heat here in Valencia. Last year when I returned my LNB showed signs of having been "cooked" in the sun so I want to avoid this happening again this year so I propose simply wrapping it up in a cloth then putting aluminum foil around it to reflect the worst of the heat. The other option perhaps is to unbolt the LNB body from the feed horn and just keep it indoors. As I won't be touching any of the focal or skew settings by doing this it should go back perfectly when I return! Any views on the best preventative method?

 

[Topper]

Bad move as the heat transfer through the aluminium will cook the lnb electronics as heat will not be able to escape either much the same as a with a chicken. Try shading the lnb from the sun if at all possible whilst maintaining airflow

 

[Robbo]

You could try covering the dish up, then there will be no heat onto the LNB.

Though I think taking the LNB off would be the best option, if you can be sure that you can put it back exactly as it was. Adjustment of the LNB can be critical in fringe reception areas.

 

[ralphmagno]

hello,
wrap it in tin foil shiny part out.
remember do not cover the opening or you will not get any signal through.
that should take care of summer heat.
ralph

 

[Topper]

Ralph he doesn't want signal through he will not be using it during the summer, wrapping in tin foil will reduce cooling not increase it,

 

[Huevos]

late June to early Sept

The heating effect due to solar radiation is no different between late June and September than it is from April to early June. The only difference is the air temperature is a few degrees warmer, not the power of the Sun. Personally I haven't seen any elevated failure rate of LNBs over the summer months.

 

[adonis1]

The heating effect greatest risk from the sun radition for an lnb , it can be happen only during Sun Outage season , mid March -early October with large dish and long time period , following the sun orbit tο observe the satelite effect .
-http://www.satellite-calculations.com/SUNcalc/SUNcalc.htm

 

[Terryl]

Just paint the LNB with a nice flat white outdoor spray enamel, cover the LNB eye with painters tape and remove it after the job is done.

Dishes not only reflect RF but visible and invisible light, In-fared does a number on the LNB even when the sun isn't directly in front of the LNB, internal temps can go way above the 50 degree C design spec during the summer, a quick sun shield can be made out of a plastic coffee can or large plastic soda bottle, just cut to fit, paint it to match.

 

[Channel Hopper]

It might be the heat is being reflected from the roof the dish is installed on. In this case the option would be to install the dish upside down on the pole.

Only offset dishes can be fixed with this technique though

 

[ralphmagno]

hello, sorry i thought he wanted to use it.
ok it is a fact that dark colors absorbe heat and light reflect..
if the lnb is black it will be hot in the summer time and light gray or white will be cooler.
wrapping it in aluminium will reflict the suns rays causing the lnb to stay cooler.
i can not think the sun is hotter where he is than naples italy.
we worry about the salt water rusting the thing out.
ralph

 

[joddle]

Wow so many opinions, thanks - looks like wrapping may be a bad idea, I follow the logic of it adding to the cooking process. I don't want to affect the alignment of the dish as it is 2.4 mtrs and works perfectly at the moment so really don't want to be messing with that. The best options seem to be to either shield it or remove it. I suppose could shield it with a blanking plate mounted on the LNB arms of the dish to stop reflected radiation and heat and some form of shield behind the LNB also to stop direct heat although that may be more tricky to do than it sounds. All in all removing it may be the best option. The four bolts hold the LNB pretty securely to the feed horn and I cant really see that when it's put back it will change anything. I fact thinking about it, when the LNB was changed last year no realignment was needed - the new LNB was simply bolted on the FH using the same holes. A third option is of course just leave it alone?

 

[Huevos]

Joddle, personally I'd just leave it alone. If it is an Invacom C120, or a White-Tech it is a white LNB anyway so won't be so susceptible to heating up in the sunlight. It's not going to be heated by the dish focusing sunlight on it because the sun is so far from the focal point, but anyway even at the 2 times of the year (a few days in the spring and autumn) when the sun does cross the focal point this is just for a few minutes and although this cause signal degradation this is only a selectivity issue and not due to overheating. One other thing, leave the receiver unplugged so you can be sure the LNB electronics are not active (Sky boxes leave the LNB powered even when they are in standby so need to be disconnected from the mains to power the LNB down).

 

[joddle]

Joddle, personally I'd just leave it alone. If it is an Invacom C120, or a White-Tech it is a white LNB anyway so won't be so susceptible to heating up in the sunlight. ).

Hi - its is an Invacom c120 quad and is white as you say so perhaps I will simply unplug everything and leave well alone. The reason I was worried is because last year when I returned from the UK in September and conncted up, many channels appeared to be down or not working and on asking about this on this and other forums the general opinion was the LNB had overheated. However later (only a few days later) the sensitivity seemed to return and it has been working fine ever since with virtuall 24/7 coverage of all channels - so perhaps it was not heat but atmospherics casuing the problem!

 

[Terryl]

I have several installs using Invacom LNB’s down by Death Valley, the temps down there get to about 50 to 55 degrees C during the summer and I have had no problems with those LNB’s.

An over the top sun shade could be made for the LNB if you think that’s the problem, but it should be plastic as to not affect the signals from the satellite. (unless this is an offset LNB type dish)