C-band parts search

[bubby-joe]

I'm looking for a C-Band dual scale ring, one that will take 2 c-band lnbf's or 1 c-band and 1 KU lnbf side by side for a prime focus dish, not a ku mount for multi KU satellites. Shape not real important just not bent or cut up to bad, paint not a problem. I can't find anything local, meaning North America. All the local shops look at me like I've got 2 heads and ones out of sight, guess where.

 

[pipino]

I'm looking for a C-Band dual scale ring, one that will take 2 c-band lnbf's or 1 c-band and 1 KU lnbf side by side for a prime focus dish, not a ku mount for multi KU satellites. Shape not real important just not bent or cut up to bad, paint not a problem. I can't find anything local, meaning North America. All the local shops look at me like I've got 2 heads and ones out of sight, guess where.

check your PM ;)

 

[bubby-joe]

Thanks , but both of the links you PM'ed me are not what I'm looking for, it's just the scale ring but it's a dual to take two c-band corotors at the same time. I'll attach a picture it's very small and very close from a magazine but it shows what I'm looking for. With this I should be able to use a corotor in one hole and a prime focus Ku band lnbf in the other at the same time. I hope there not to fuzzy. Again just the scale ring is what I'm after.

 

[Channel Hopper]

From those pictures it does look like somebody has machined one corotor ring to slot next to the other. There are two possibllities for its use;
1) to catch two satellites simultaneously no more than a couple of degrees apart.
2)to be able to retain a reasonable signal by switching LNB every twelve hours on one inclined orbit satellite.


I can see the advantage in terms of cost, no motor required, and certainly no second dish. This would most likely be at a cable headend. I doubt very much if it is something that comes from a manufacturer.

 

[pipino]

Thanks , but both of the links you PM'ed me are not what I'm looking for, it's just the scale ring but it's a dual to take two c-band corotors at the same time. I'll attach a picture it's very small and very close from a magazine but it shows what I'm looking for. With this I should be able to use a corotor in one hole and a prime focus Ku band lnbf in the other at the same time. I hope there not to fuzzy. Again just the scale ring is what I'm after.

ahh now i seen what are you looking for!!! i know a place where to get them from ,i will resend you a PM ,,,the unit is made by a chinees company called gospell and the model is GCF-D22C ..cheers

 

[bubby-joe]

It's available commercially mostly in Asia/ China but it probably is someone made one and someone else copied it. But it's not available in North America that I know of. And a picture is better than a thousand words.

 

[pipino]

With this I should be able to use a corotor in one hole and a prime focus Ku band lnbf in the other at the same time. I hope there not to fuzzy. Again just the scale ring is what I'm after.

or may be this better for your application???

 

[bubby-joe]

I don't want to use a DSS lnbf, as there not matched to a prime focus dish and will only see a small portion of the dish, approx 1/3rd of a 10/12 foot dish is OK for signal quality but a 6 footer falls short, equal to an 18 inch dish but no more. limits Ku to 5 satellites all DSS birds and linear satellites to Zero.
I'm putting it on a 6 ft andrews solid spun aluminum on an Orbitron SX spin mount and for it to work it requires the PHF-031 and the ADF-120 scale ring plus a c-band scale ring to give adequate performance from the Ku side. the c-band digital and the 6 ft dish is more than adequate for good signal quality this is why I'm looking for this particular scale ring.
Driven by a V-box III and a 24 inch Von-Weise actuator controlled by a Pansat 2500a FTA box and DiSeqC 1.0 or USALS commands.

 

[pipino]

sorry from your first request it was not clear for me what do you have exactly and what you wanted to do!!¿ ,now after few PM exchange i understand the full picture ,i got realy confused at first when you mentioned LNBF ,the definition on LNBF is LNB+feed in one block (like used in offset dishes),in your PM you told me that you have an invacom with adf120 feedhorn ,that´s not an LNBF thats a Flange LNB +C120 feedhorn,anyway we know now what type of scalar ring you need so i wish you luck to find it somewhere ,,by the way using that scalar ring will still give you some problems holding the adf120 unless you have another idea to hold it,,all the best..cheers

 

[bubby-joe]

Close, difference between an LNB and an LNBF is how there polarity is switched, an LNB is single polarity and requires some form of servo motor or extra device to switch from vertical to horizontal and an LNBF usually has built in switching by line voltage, 10-13 volt for vertical and 14-18 volt for horizontal in the coaxial cable from the receiver but in the end they both do the same job they convert TP frequency to something you either see or hear. The QPF-031 does both linear and circular KU basically 2 LNBF's in one and has dual polarity voltage switching making it 2 LNBF's and the ADF-120 is what it uses to properly concentrate signal on a prime focus dish. This married to a C-band LNBF in a dual scale ring on a motorized prime focus dish gives me the world with only 2 LNBF's and 1 4X1 DiSEqC switch, FTA receiver and a V-Box. I suppose I could cut up 2 C-band scale rings and have them welded back together after playing with the angles. If one's not available in North America then that's my last option build it from the scrap pile. I plan to hold the ADF-120 in the scale ring with a machined hockey puck, or a rear mounted 40 mm collar clamp, hockey puck very similar to what I use to hold a 40 mm throat LNBF in a 39 inch starchoice dish instead of there stacked LNBF. Same as my gun sight laser is mounted to center the scale ring on the dish only 40 mm mount hole.

 

[bubby-joe]

Channel Hopper the picture came from an ad in TelleSatellite International from a couple of years ago from a dish manufacturer, the item came originally out of Indonesia. And Pipino sent 2 URL's for one similar item from China and something different that used a side mounted DSS LNBF and will not work for what I'm trying to do. But after going thru my satellite scrap pile I found 2 identical c-band scale rings so I may be able to cut both and hold them back together with an aluminum plate from the rear side for now I'd like test this mount idea.

 

[starman345]

. Same as my gun sight laser is mounted to center the scale ring on the dish only 40 mm mount hole.

Got a picture of your gunsight laser? I've been trying to figure out a mount for my laser pointer to center my lnbf in the dish. Hockey puck with a hole in the center for the laser might work!

 

[bubby-joe]

Got a picture of your gunsight laser? I've been trying to figure out a mount for my laser pointer to center my lnbf in the dish. Hockey puck with a hole in the center for the laser might work!

Coming up ::: The small silver tube has a dollar store tiny laser in it. Some of the best tools are homemade. White plastic holder goes to the bottom of the scale ring without touching the lnbf. I originally used a hockey puck cut down to fit the scale ring fairly tight and used an auto sectional collapsing radio antenna in the 1/4 inch hole where my mandrel mounted to the drill press, went to the laser for over 36 inch focal depth to the dish face.

 

[starman345]

Great stuff! Thanks for posting those pictures. I have a GeosatPro Ck/1 lnbf that fits very sloppily in the supplied scaler ring. Being a c/ku lnbf I am trying to set it up accurately on the 10 footer to get decent ku. It is working now but I think I could get more signal......I always seem to think that
I like your plastic insert, I think getting the lnbf at 90 degrees to the scaler would come first, then center the whole unit with the laser should get things lined up pretty well. I should be able to do that by adjusting the scaler with the bolts in the slotted support arms of the dish. So many things to get right, f/d, focal distance.
Thanks for the pictures, you've given me more to think about

 

[Channel Hopper]

Coming up ::: The small silver tube has a dollar store tiny laser in it. Some of the best tools are homemade.

Nice piece of kit there, and agree with you, homemade often beats what you get in the stores.

(By the way, has Canada broken off from the large lump and drifted over this way ?)

 

[starman345]

(By the way, has Canada broken off from the large lump and drifted over this way ?)

Just a matter of time, we'll be taking over Actually Canada IS the "large lump", the rest of North America is hanging on to us and won't let us go.

 

[bubby-joe]

What starman 345 said, your all welcome the pictures explain a lot better than I can verbally. The reason I'm looking on your side of the pond is that no satellite shops here know anything but the little pie plates any more.. I had to teach myself to install the c-band setup from scratch, parts here are free I use a homemade atv winch setup to remove the dish from the pole then recycle what I can, right now prices are down so I have 5-10 footers a 12 and lots of pie plates in the scrap pile, Oh yah and an aluminum boat and a huge pile of analog receivers under 6 ft of snow.
Starman the scale ring is more important to be right on than the lnb in the mount, just use small metal shims to keep it square and don't over tighten, I had a geosat and gave it away to a machinist friend that made a tapered split ring adapter to shim it straight, he taps the tapered ring in from the rear to align it, kind of like a tapered wheel nut lock on a military truck, the scale ring that came with the geosat lnbf was tapered the opposite way to the lnbf tube taper making for an impossible fit the scale rings in the scrap as well, the focal distance and scale ring alignment is critical and the Ku linear skew adjustment to your true south satellite are some my little hints to better performance.

 

[starman345]

The tapered split ring adapter sounds like a good idea, never thought of doing it that way. I found an old feedhorn in my basement this morning, just an old cband I used 20 years ago but the scaler is a perfect fit for the geosatpro, nice and thick so the lnbf will sit square in it, and it has two "real" set screws...allen wrench type. I'm going to build a laser pointer holder using some of your ideas. I have a hole saw that will cut a piece of wood the exact diameter of the lnbf throat so I think I'm going to go that route for now and see how it works out. Now I just need to set up my drill press so everything is at 90 degrees.

 

[bubby-joe]

The one I had was so tapered that to align it in it's own scale ring would have been a nightmare. I swapped it for another lnb. I went with the BSC-621 way better finish quality and no problems with alignment in a chapparral scale ring, it also has 2 tension screws. You be careful with the C-band barrel on most of them is quite tapered making alignment very hard and don't forget you can't tighten very much you still need to rotate for the final skew adjustment to the Ku linear on your true south bird and you could still wind up with a misalignment. Try a hose clamp around the lnb to bottom out when you set the skew and keep the focal depth,skew and final dish alignment kind of makes me think I should have 3 extra hands but I know that would look weird. Another thing is to use tapered wooden tooth picks as temporary spacers to hold the alignment until all setup. You can't use the wooden plug or hockey puck idea on a chapparal c/Ku corotor as the little platic Ku skew control comes out to far but the plastic alignment tool worked because it didn't touch the lnb corotor combination

 

[bubby-joe]

We got a little off track here but I've decided to make my own scale ring from 2 older astrotel scale rings with a new metal plate backing so I can try to get both LNB's aligned to the center of the dish. I figure to dish the joined scale rings to get both to see the center of the dish. Gives me something to do till the snow pack starts to go. Lucky me we have 5-6 ft of white stuff and winter just started snow usually slows in mid April/May, somebody toss in a long rope in late February