Can LNB Degrade

[markinstien]

Could anyone tell me if LNBs can degrade or lose sensitivity as when I first installed my dish With pace box 810 could easily pick up AMOS Nilesat 1, 16 degrees on 95 cm dish, I then purchased a TM 6900 and lost Nilesat and AMOS and used it for the last two and a half years. I have now purchased a spiderbox and can barely pick up 16 degrees.Does anyone think the LNB may be needing replacement (Have spare Lemon Universal from purchase of TMate) or is it the boxes just aren,t as good at recieving/sensitive as they once were?

[mahler]

The Spiderbox has an extremely sensitive tuner, and if anything is probably better than older boxes of other makes.

The most likely cause is deterioration of the coaxial cable, maybe due to water ingression especially at the dish termination.

If it's not too great a cable run try a temporary cable through an open window or whatever this will prove the point.

Regards mahler.

[Detlef]

Yes they do degrade.

Several things can happen including an increase of noise and shift in the local oscillator frequencies. Water ingress can be a problem after many years of operation too.

The tuners in a box can degrade but usually other problems occur before that shows. If you are using an LNB switch with 2, 4 or more LNBs then you can compare the performance of one sat with another.

Try the spare LNB - you have nothing to loose. Also before spending real money remake all the "F" connectors on the cable from the LNB to the receiver as the first few centimeters of the cable can suffer water ingress.

Providers also move the beams on the sats so it is possible that the AMOS footprint has changed - I don't use that bird so can't comment.

[satwyn]

as you have also changed your receiver the tuners are also a factor as are the dish and cable

[Burnham]

You can't compare 16°e reception now with your results from two years ago as most transponders are weaker having been switched to a new satellite.

If you want a check on current reception please say where you are located and people near you can say what you can expect to receive with a 95cm dish.

As a guide I am located in SE England and get good reception of all 16°e transponders on a 80cm dish in most weathers with a 5 year old LNB.

[brain]

hi
As has been said above they do lose efficiency.1 The water ingress via the very thin cover. 2. Water via the lead - if the insulation breaks down or was not that good to start with. 3. Some TMs do have problems with upper range of TP's. 4. if not fully secure they may rotate in time and this can also be crucial. Good Luck - Brain

[markinstien]

Thanks guys I am north Manchester area recieving 75% strength 40% on (39E) Bulsat and borderline pick up of supersport transponders 80% strength 38-42% Quality on Eutelsat (16E), Ill try new LNB tomorrow .

[dale094]

i have fitted many 90cm orbitals on 15.8 around manchester and get 75% sig upper 80s qty

So your dish should more than do the job.

[markinstien]

Anyone recomend Motorised dish installer to replace my LNB and maybe trim my dish North Manchester area / not a roof job but wall mounted.

[johnhenry]

markinstien i agree with mahler with regard to the Spiderbox i had a Manhattan on which i had an 80 cm dish with 3 lnb's 19e 13e and .08w when it was cloudy with heavy showers i always lost .08w and winter time was a waste of time on Thor, but since connecting my Spiderbox on to the same dish and lnb's i lose nothing even on Thor during heavy cloud or even snow showers, my lnb's are now coming up to two years old and still working well and just laterly i have been getting the strongest signals i have ever received. Dont know at what time of day you were experiance signal problem but some times the sun gets low in the sky and faces directly into the dish which does cause signal problem. A couple of years ago i was watching a programme on 19e around this time of the year when the signal dropped right off went out side and noticed the sun shinning diirectly at dish, waited about 15 mins and signal strenght came back. But can say Spider good box for strong signal receiption. Noticed others stating problem with signal on 16e. Best johnhenry.

[mahler]

For quite a long time in this hobby we have become obsessed with Lnb noise figures, and some of the manufacturers claims are beyond belief, and clearly aimed at improved sales.

However there are certain very good Lnb's and Lnbf's and they don't always possess 0.1, and 0.2 dB noise figures, and it's very easy to overlook the system overall noise contribution of the satellite receiver front end tuner, which can easily spoil a low noise Lnb.

I believe the recognition of this fact has lead receiver manufacturers to concentrate more on low noise devices in their tuners, and the Spiderbox is a good example of this.

Regards mahler.

[dale094]

Markenstien.

tried to reply to your message dont have enough posts so will bring them up

I do install satellites motorised and any other i will pm you if you still need my services.

[dale094]

markenstien.

Personally if i was you i would go with Inverto ultra to compensate

[johnhenry]

i agree with dale094 my Lnb's are Invento Silver Tech IDL Universal HD Ready got the empty box in front of me now also states 5 year warranty but again would imagine the ultra is a more up-to-date Lnb as i bought mine 2 years back. They certainly are good quality.

[highway1]

an lnb life is 1 day to years of service. but

full sun can cook them /
ice or snow can block sigital .
coax can get water in which cause problems .
wind can move the dish so lnb is ok !!
lnb life is 1 day to years of service i changed to 0.1db 2 years ago been ok so far .

aiso note that satelite in space lower power after 9pm? for night use to stop uk etc watching them . ((( note 5 east does )))