Let's Talk Feedhorns

[PopcornNMore]

Getting on soap box...

Why are today's LNBF's so cheaply built?

The Chaparral (Welcome To Chaparral Communications) feed horns I purchased in the 80's were far superior.

My pet peeves of the LNBF's manufactured today are as follows:

• Very lightweight and cheaply built.
• Set screw moves feed off center and even jerks the feed from not being straight.
• The cap ALWAYS comes off in time and bees then have a nesting place.

Last night while adjusting a WS International single C-band LNBF I became frustrated by how these LNBF's use only 1 set screw to hold it in place within the scalar ring. I found not only does this markup the outer housing which can create rust the screw also moves the center of the feed off center.

Has anyone ever tried using a gasket around the feed before inserting it into the scalar ring to keep it centered and to avoid the screw from marking up the housing? I did this last night and it worked rather well. I'll try to post a picture this weekend.

I also wish the cap was like the Chaparral brand and fitted a lot more securely.

I'm not knocking WS International's LNBF's. In fact they work really well when properly adjusted. It's just that all LNBF's manufactured these days just don't compare to the quality of feed horns manufactured years ago. I guess this is true with most products.

Getting off soap box...

 

[turbosat]

Agreed, Popcorn, but I have a couple of cheapo lnb/feedhorns that are the same way, bought 4-5yrs ago. Set screw will hardly hold the feedhorn straight as you tighten it, aggravating to adjust. Would like to find affordable lnbfs for Cband, that are built a little better.

 

[Mr Tony]

I strill use the older scaler rings to hold the newer LNBF's in....while it still makes a mark the older ones seem to "hold" the LNB in there better

now to find a bunch of those small screws that are on the old school scaler rings

 

[guapoharry]

To avoid tearing up the feed with the cheap-o scalar setscrew, I insert a shim made of steel can to take the abuse.

 

[Mr Tony]

harry
that sounds like a good idea. Since the "port-a-bud" gets aimed at various sats that would come in handy

 

[PANHANDLER]

I also found this prob with the single set screw , very diffacult to keep the lnb centered especialy when aiming for ku . What i found that works for me is to insert 2 shims approx. .100 thick at 120 degrees from the set screw ( 120 - 240 degr. ) By using this method it allows the lnb to me seated at three points instead of two ( set screw and bump on scaler at 180 degr. )

 

[Anole]

To avoid tearing up the feed with the cheap-o scalar setscrew, I insert a shim made of steel can to take the abuse.

Year or so back, I came up with (and thought I posted about), an aluminum shim to use on a Ck-1 or C2 LNBF.
It is captured by the screw head, so it won't fall away if you pull the feed.
Also prevents the concave screw point from making a mark on the feedhorn.
It's about half (?) an inch wide, making for easier 'n smoother alignment.

A big problem with some feeds, is that they taper a bit, from the open end to the LNB end.
So, moving 'em in and out will let 'em wobble.
I didn't come up with a solution for that.


But as for the finish, I'm somewhat underwhelmed by a Chaparral feed I'm working on.
It has paint peeling/bubbling.
I don't think the metal was properly prep'd, and doubt this is powder coating.
The bare metal is somewhat pitted and corroded in areas.
Particularly worried about the interior of the plumbing... it's not so bad, but I want to clean it carefully.
I'm working on some pictures for another thread to show the deterioration.
There, I will ask for suggestions. (not here)
Darned thing doesn't have F/D markings, either, but I found measurements on their site.

 

[PopcornNMore]

I also found this prob with the single set screw , very difficult to keep the lnb centered especially when aiming for ku . What i found that works for me is to insert 2 shims approx. .100 thick at 120 degrees from the set screw ( 120 - 240 degr. ) By using this method it allows the lnb to me seated at three points instead of two ( set screw and bump on scaler at 180 degr. )

I thought about using popsicle sticks.

 

[LocutusOfBorg]

I found that the scalar for my Geosatpro C2 lnbf to be of inferior quality also. I actually managed to break the scalar! That was disappointing. I had an older, sturdier, Chapparal scalar laying around and I'm using it now. I don't know if any of the solidly built scalars are still available but I haven't looked for any lately. I'm disappointed in the quality of my new KTI dish, also, since the ribs are made of aluminum and can be easily damaged.

 

[LocutusOfBorg]

I also found this prob with the single set screw , very diffacult to keep the lnb centered especialy when aiming for ku . What i found that works for me is to insert 2 shims approx. .100 thick at 120 degrees from the set screw ( 120 - 240 degr. ) By using this method it allows the lnb to me seated at three points instead of two ( set screw and bump on scaler at 180 degr. )

I suppose an alternative is to drill and tap another hole for a second setscrew.

 

[Skyscanner]

If the horn was straight like the Chaparral instead of tapered like the newer ones, this would go a long way in fixing these problems. Then a few wraps of electrical tape would be the shim and protect the horn from being marred by the screw. Contact cement hold the cover in place well.

 

[Tron]

The scalar rings that came with my Eagle Aspen B1SAT stacked LNBFs are actually of heavier build than most of the newer rings. Not sure if Sadoun has any more of these LNBFs, but they seem pretty sturdy.

 

[Anole]

The scalar rings that came with my Eagle Aspen B1SAT stacked LNBFs are actually of heavier build than most of the newer rings.
Not sure if Sadoun has any more of these LNBFs, but they seem pretty sturdy.

I ordered my B1sat back when he supposedly had LNBFs but no scalars.
So, I always assumed the one he included was something kicking around the warehouse.
But it was a -brute- ! - :up
Easily the equal (or better than) the few Chaparrals I've seen.

 

[Corrado]

I have tried a few different approaches. This seems to work for me.

 

[caddata]

I thought about using popsicle sticks.

Oh no please don't tell us if you decide to use Popsicle sticks because, if you do, from that point on you'll be "PopsicleNMore" in my mind.

Sorry for the sick humor.

 

[ACRadio]

The scalar rings that came with my Eagle Aspen B1SAT stacked LNBFs are actually of heavier build than most of the newer rings. Not sure if Sadoun has any more of these LNBFs, but they seem pretty sturdy.

I have 2 of them for sale...

 

[eurosport]

I have tried a few different approaches. This seems to work for me.

Wow, hose clamp & all, that bad boy's really sticking out of that scalar!
Mine are about 1/2 inch out at the most.
If I did 'em like that, I don't think they would pull in anything!

 

[GreatFTA]

I strill use the older scaler rings to hold the newer LNBF's in....while it still makes a mark the older ones seem to "hold" the LNB in there better

now to find a bunch of those small screws that are on the old school scaler rings

I do the same thing. I see newer scalar rings so flimsy that if I drop it can bent the outer edge. The older rings are built thicker and hold the newer LNBs better.