Gibertini Feedhorn

[Costactc]

I just received my new Gibertini feedhorn C120. This feedhorn will be used in combination with my invacom twf-031 flange lnbf and on my 4' dish. They didn't send me the neck clamp for a 40mm throat so I will have to mod something. It's pouring rain here today so this will have to wait until tomorrow:

 

[Captain Jack]

Will be interesting to see your results.

 

[Costactc]

Slapping on today as the weather has improved. I will post reults.

 

[Archive-8]

Good luck with that :-)

 

[Costactc]

I will have more detailed results but overall there has been an increase in db level from sat to sat from Amc 6 at 72w to Amc 1 at 103w with modded collar as the original is on its way.

 

[Captain Jack]

Is that on the 1.2m Gibby?

 

[Costactc]

1.2m Fortec:

 

[RimaNTSS]

Nice install. Seems that dish has mileage, so, little bit rusty. Couple of provocative questions:
- Are you sure LNB is located in true dish focus?
- Are you positive LNB is pointed to the right spot?
Please elaborate

 

[Costactc]

That dish will be replaced next Spring with a new Geosat 1.2m. The db levels are higher then with my previous invacom lnb so I'm quite sure it's located properly. I'm waiting for its original collar to be sent as it should have been, I modded one by myself.

 

[RimaNTSS]

It might happen that after placing LNB to true antenna's focus and pointing it to right spot, db levels would rise even more! Did you try to put Inverto Black Ultra on this dish?

 

[Costactc]

It might happen that after placing LNB to true antenna's focus and pointing it to right spot, db levels would rise even more! Did you try to put Inverto Black Ultra on this dish?

Yes I did put the Inverto lnb on the dish and this feed is outperforming it. I will wait for the weekend to tinker with it to see if I can elevate those db levels.

 

[RimaNTSS]

Without knowing exact location of focus, it is very hard to experimentally find it. I am trying to say that focus should be calculated and not to be searching by tweaking of system's adjustments (azimuth, elevation, skew, variety of positions of LN.
Example: You have not properly adjusted antenna (azimuth, elevation), and by tweaking of LNBs you are able to find maximal signal. Does that mean you have your LNBs in focus? Change antenna's position and tweak LNBs again, and you will be able to find maximum signal again. And levels of those signals could be same. So, where is focus?

 

[Costactc]

I haven't calculated focus at all just skewing which I will do this weekend when I have more time. The dish is properly aligned and on the arc.