Question - Invacom QPH lnb - broken protective brown film

[mxxuk]

I have a question related to my good and trusted so far Invacom lnb.

All working like a charm until today when the brown semi-transparent film that is covering the horn's end/entry (pointing to the dish focal center) was broken. Do not ask how or when ... I suspect it was some hungry woodpecker because looks like it was hit mutiple times by some kind of spike.

Now my signal is gone. Does the film plays any role ? I suspect it does because on some transponders I get over 95% signal quality and on some none. I tried readjusting the antenna slightly and the I get another transponder really strong ... and so on. Dos anyone knows for sure if the protective film has any role. I suspect it was acting like a lens focusing the signal ....

Just to be sure I don't spend 100$ just because I don't know...

What to say ... Stupid bird !!

 

[qwert1515]

It only protects the dipole inside (and keeps moisture out). Make sure it is dry inside the LNB and then you can tape (Electric or Duct) the LNB up, I once had a plastic trash container covering my dish and I didn't see any signal drop

 

[rv1pop]

It only protects the dipole inside (and keeps moisture out). Make sure it is dry inside the LNB and then you can tape (Electric or Duct) the LNB up, I once had a plastic trash container covering my dish and I didn't see any signal drop

I would not use duct tape as many of them are metalic. Box (packing) tape might be better, or plastic wrap (Saran wrap or equivalent) held in place by good electrical tape.

 

[Anole]

is that Kapton film ?

Yes, it's just there to keep the bugs 'n weather out.

Some time ago, we joked around about using plastic lids off liquid washing detergent, or caps off aerosol deodorant.

Whatever plastic you choose, it's easy enough to test if it affects your signal.
Get a signal without the plastic, then hold the plastic in place by hand.

I may be wrong, but what I see over the face of my Invacom LNB, looks to be Kapton plastic film.
Looking down inside Dish Network bandstacked FSS LNBs, I thought the same thing.
You can read about it on the DuPont site, or Wikipedia may have an [ame="http://en.wikipedia.org/wiki/Kapton"]Kapton - Wikipedia, the free encyclopedia@@AMEPARAM@@/wiki/Fileoly-oxydiphenylene-pyromellitimide.png" class="image"><img alt="" src="http://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Poly-oxydiphenylene-pyromellitimide.png/220px-Poly-oxydiphenylene-pyromellitimide.png"@@AMEPARAM@@commons/thumb/8/8f/Poly-oxydiphenylene-pyromellitimide.png/220px-Poly-oxydiphenylene-pyromellitimide.png[/ame].
See Google for Kapton tape, with adhesives for all applications.

If in fact they do use Kapton, it may be because it will hold up in all sorts of conditions, and handle the UV bombardment of outdoor use.
Whatever you choose to use, put a second piece out in the elements where you can easily inspect it.
From time to time (every few months), check the sample for deterioration.

Hey, you know who might know what they used?
Maybe Brian of SatelliteAV.
I wonder if replacement discs are available?

 

[mxxuk]

Here is an update - after few hours of antenna orienting. I never had such a headache pointing a dish in my life which really makes me believe something is really wrong with my LNB.

Just for record, I was in a 2 weeks vacation, I left everything in good condition and when I got back I found the film broken and signal partially gone.

My setup is: Fortec 120cm antenna, STAB HH120, Invacom QPH-031 and Pansat receiver + a DVB Twinhan card.

I still get signal on two TP's on Echostar 7 (119) but nothing else works (not even 1% quality). Level is 98% ... On the two TP's I get the quality is 97-98% ... so I point straight into the satellite no question about it. Something similar happens on Echostar 8 (110), two TP's with awesome quality and the rest gone. Echo 8 is almost in the true south (2.7 degrees off) - I am in Phoenix AZ.

I cannot lock on linear Galaxy 25 (the old T5) in any way. All gone.

Also tried the card and receiver ... same results.

All this after 4 hours or double, triple checking everything. No matters what I try, still no signal.

I have an old universal LNB (linear only) - I-ll try to lock on G25/T5 ... if that one works then my Invacom is gone. Probably the dipole is misaligned ... these stupid woodpeckers are really strong
BTW .. the same two transponders were working before starting to re-align the antenna.

 

[Anole]

Yes it's possible you have mechanical damage.
I would armor up the new one with one of the plastic lids described above.

But it could also just be moisture inside the unit.
See if you can dry it out completely, perhaps with a hair dryer, as a last resort.

 

[Cadsulfide]

the cover from a old dbs lnb can be used