i put my bullseye II c/ku dual feed on

[truckracer]

I had decided to put the bullseye back on after running the corotor for a year or so.
i have some agile channel modulators and thought i would modulate a couple more channels into my antenna stream so i needed to be able to run a multiswitch to accmodate a couple more receivers.

to my surprise..the bullseye had been laying around in a storage building-it had all this white oxidation crud inside it. i removed the lnbs and tried cleaning most of it out.
put the lnbs back on and put it on the dish.

reception was not nearly as good as my corotor II. Ku and c was both down quite a few points over the corotor. I thought in the past when i used that feed it was as good or better.

could that chaulky white crud cause poor signals?

 

[Anole]

glad you brought this up

I have a used ortho with a similar problem.
Not sure how to clean the inside, and uncertain what I might put on those surfaces to protect them.
This may sound odd, but I have contemplated using a light coating of aerosol furniture polish on a rag, then rubbing it into the porous surface.
. . . but I'm looking for a better answer.

The paint on the outside has flaked off in areas, and the aluminum (?) is chalky underneath.
I don't think regular flat gray primer will really stick, but at least the outside is far less worrisome than the inside. -

Maybe one of our metal masters will have a better idea, but I thought the one and best way to protect aluminum, was with a zinc chromate coating.!.?.
As a primer, that is... if you want to hard anodize, that'd be far better.
Why the hell are these feeds not coated or protected better.?.!

Mine's a C-band only, Chaparral.

 

[truckracer]

i put it on and my signals were awful. starz on G1 was down to 84% with my best tuning. 99% with the clean corotor II!
Ku band was also bad. i was getting poor ku signals on AMC-21 and poor c band on G14. TBN HD was 60% quality...its 90% on my corotor II. PBS was down to 39% quality where as its usually 80% on corotor. I just couldn't get it to work well and the only thing thats changed is the white crud!!

 

[FaT Air]

cruddy white stuff I believe is aluminum oxide. aluminum rust if you will. I know GE had trouble back in the 80's with a line of radios. The helical resonator cavities would do this and detune them. Sometimes the corrosion would grow into "whiskers". Can't remember what they supplied to "paint" them with after cleaning. I want to say it was just a clear lacquer. Wouldn't doubt the corrosion also is internal and not just in the throat, detuning the LNBF passband.

 

[truckracer]

It is all the way through the ku waveguides too. I am going to try to clean it out with a dremel polishing tool and spray the inside with a light coat of non metalic laquer or some finish.

 

[truckracer]

Today using steel wool and a sharp knife I scraped and polished all the white oxide out. It's pretty shiney aluminum now. I also disassembled the ku waveguides and cleaned them out too. Reassembled the four lnbs and waiting til late tonight when I get off work to try it out!

The ku lnbs had heavy aluminum oxide buildup on the "window film" tha covers the openings of the ku lnbs. Thick and white!

 

[beavs2112]

cruddy white stuff I believe is aluminum oxide. aluminum rust if you will. I know GE had trouble back in the 80's with a line of radios. The helical resonator cavities would do this and detune them. Sometimes the corrosion would grow into "whiskers". Can't remember what they supplied to "paint" them with after cleaning. I want to say it was just a clear lacquer. Wouldn't doubt the corrosion also is internal and not just in the throat, detuning the LNBF passband.

i forgot about g.e. receivers having that issue. forget the model but we used them at a paging (beeper) company i used to work for. cleaned them with steel wool and sealed with clear laquer in a spray can.

I have a used ortho with a similar problem.
Not sure how to clean the inside, and uncertain what I might put on those surfaces to protect them.
This may sound odd, but I have contemplated using a light coating of aerosol furniture polish on a rag, then rubbing it into the porous surface.
. . . but I'm looking for a better answer.

The paint on the outside has flaked off in areas, and the aluminum (?) is chalky underneath.
I don't think regular flat gray primer will really stick, but at least the outside is far less worrisome than the inside. -

Maybe one of our metal masters will have a better idea, but I thought the one and best way to protect aluminum, was with a zinc chromate coating.!.?.
As a primer, that is... if you want to hard anodize, that'd be far better.
Why the hell are these feeds not coated or protected better.?.!

Mine's a C-band only, Chaparral.

i gonna go with money being the answer to why they're not protected better. surprising though for chaparral.

 

[truckracer]

Chaparal may not have intended on those units being in service so long! We have all continued to maintain most o our equipment beyond it's life expectancy. Just like our 4DTV receivers...I am sure motorola never expected users to change the CMOS battery.

 

[truckracer]

Put the bullseye back on after cleaning-it works much better