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Hi guys,
I'm working on some replacement "arms" to hold my scalar ring and LNBF on a 10 foot dish. The old arms are weak and rusting out badly.
Previously when I put the dish up, I simply assembled everything, and adjusted the LNBF in / out of the scalar ring, but I didn't pay attention to the f/D ratio because I didn't measure and calculate it. This time I'd like to do it a little better by measuring things and getting it right. I've measured the dish with a string test (fishing line works well), and come up with a f/D ratio of approximately 0.34 and a focal length of approximately 41 inches.
Knowing that the focal length is ~41 inches, where do I place the scalar ring, and the front lip of the LNBF?
From what I understand, the LNBF should tightened on to the scalar ring at the f/D ratio (0.34) first. From there, the front lip of the LNBF with scalar ring should be placed about 1/4 inch closer than the focal length, so 40.75 inches in my case. Once that's correct, I tighten the new "arms" to hold it all in place, adjusting the arms / scalar ring attachment points to get the focal length correct.
Does this make sense? Am I misunderstanding something?
sgs
I'm working on some replacement "arms" to hold my scalar ring and LNBF on a 10 foot dish. The old arms are weak and rusting out badly.
Previously when I put the dish up, I simply assembled everything, and adjusted the LNBF in / out of the scalar ring, but I didn't pay attention to the f/D ratio because I didn't measure and calculate it. This time I'd like to do it a little better by measuring things and getting it right. I've measured the dish with a string test (fishing line works well), and come up with a f/D ratio of approximately 0.34 and a focal length of approximately 41 inches.
Knowing that the focal length is ~41 inches, where do I place the scalar ring, and the front lip of the LNBF?
From what I understand, the LNBF should tightened on to the scalar ring at the f/D ratio (0.34) first. From there, the front lip of the LNBF with scalar ring should be placed about 1/4 inch closer than the focal length, so 40.75 inches in my case. Once that's correct, I tighten the new "arms" to hold it all in place, adjusting the arms / scalar ring attachment points to get the focal length correct.
Does this make sense? Am I misunderstanding something?
sgs
10 Replies
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3517 views
sgs I think if you get another LNB bracket, which is fixed to the feedarms and allows LNBF to slide inside, than your problem will be solved. Than it is possible to fine tune position of the scalar closer/further from the dish. Something like that
S
Thanks for the replies guys. 
That's what I thought too. However, in the PDF that Brian linked to, it shows the f/D ratio set to the back "lip" of the scalar, not the rear smooth face of the scalar. The picture in the PDF shows the lip at f/D of 36, but if it's the smooth surface of the scalar, then the picture is actually showing a f/D closer to 39 or 40.
So, is the PDF wrong or are we?
sgs
That's what I thought too. However, in the PDF that Brian linked to, it shows the f/D ratio set to the back "lip" of the scalar, not the rear smooth face of the scalar. The picture in the PDF shows the lip at f/D of 36, but if it's the smooth surface of the scalar, then the picture is actually showing a f/D closer to 39 or 40.
So, is the PDF wrong or are we?
sgs
That bracket from picture I posted is not made by me but for me, by friend of mine. Now I also making something similar. And out of the shelf brackets also available on the market, look for star-bracket. There are some examples.
For really big (I mean huge) antennas 4 support arms is an option. In fact, I think, it could be not easy to find > than 10 foot dish with only 3 feedarms. You are right about threaded bars ability to bend, therefore it is better to use pipes with threaded bars adjusted to the ends. That, as a bonus, makes feedarms adjustable in length. Of course, bigger dish - bigger diameter of the pipes and threaded rods used.
Go with the photo. Can't argue, he's right.Thanks for the replies guys.
That's what I thought too. However, in the PDF that Brian linked to, it shows the f/D ratio set to the back "lip" of the scalar, not the rear smooth face of the scalar. The picture in the PDF shows the lip at f/D of 36, but if it's the smooth surface of the scalar, then the picture is actually showing a f/D closer to 39 or 40.
View attachment 110943
So, is the PDF wrong or are we?
sgs
S
Interesting thread. In particular Bert's post on 8/8/98:
1/4 wavelength is not 1/4 inch for C-band, it's more like 3/4 of an inch! So if that's correct, then the LNBF+scalar should be almost half an inch closer to the face of the dish. Can anyone here confirm the correct placement? I've read 1/4 inch in many places, but I could see how people might start thinking 1/4 inch instead of 1/4 wavelength!!
Unfortunately that page isn't clear on exactly how to place the scalar, only that it needs to be set correctly:
The "top edge" could be the flat part of the scalar, but I assume it's the edge with the lip, not the flat back part. Generally that would make sense to me, because we cannot see the markings where the flat back part of the scalar ring is, when installing. 
The reason this is confusing to me is because I've got a bunch of different scalar rings, and they do not have the exact same lip length. I suppose it's because the scalars I have are generally cheap garbage.
Does Chaparral even print the f/D ratios on their feeds like we see on a typical LNBF? I have one not in use, with no f/D markings.
I've read conflicting information from various sources, which is why I started this thread to verify the correct setup. Unfortunately every LNBF I have didn't come with instructions to indicate where to line up the scalar ring to the LNBF's stamped f/D ratios. Hopefully someone reads this and has instructions on it.
As the thread you linked to points out, it comes down to manually tuning it for your use case and particular dish. However I think it's worthwhile to know exactly how to configure everything in the "ideal case (theory)" as opposed to the "real world (practical)".
If the f/D ratio in my previous post with the picture is set correctly at 0.36 and that's what the dish's f/D ratio is, then everything is good. If the f/D ratio is actually 0.39 or 0.40, then it means the scalar ring is not filtering / choking the entire surface of the dish's reflective area, but a smaller portion of it. Likely this would mean more susceptibility to terrestrial interference and/or less overall gain on weaker signals, correct?
As always, thanks guys
sgs
Interesting thread. In particular Bert's post on 8/8/98:
1/4 wavelength is not 1/4 inch for C-band, it's more like 3/4 of an inch! So if that's correct, then the LNBF+scalar should be almost half an inch closer to the face of the dish. Can anyone here confirm the correct placement? I've read 1/4 inch in many places, but I could see how people might start thinking 1/4 inch instead of 1/4 wavelength!!
Unfortunately that page isn't clear on exactly how to place the scalar, only that it needs to be set correctly:
The "top edge" could be the flat part of the scalar, but I assume it's the edge with the lip, not the flat back part. Generally that would make sense to me, because we cannot see the markings where the flat back part of the scalar ring is, when installing. The reason this is confusing to me is because I've got a bunch of different scalar rings, and they do not have the exact same lip length. I suppose it's because the scalars I have are generally cheap garbage.
Does Chaparral even print the f/D ratios on their feeds like we see on a typical LNBF? I have one not in use, with no f/D markings.
I've read conflicting information from various sources, which is why I started this thread to verify the correct setup. Unfortunately every LNBF I have didn't come with instructions to indicate where to line up the scalar ring to the LNBF's stamped f/D ratios. Hopefully someone reads this and has instructions on it.
As the thread you linked to points out, it comes down to manually tuning it for your use case and particular dish. However I think it's worthwhile to know exactly how to configure everything in the "ideal case (theory)" as opposed to the "real world (practical)".
If the f/D ratio in my previous post with the picture is set correctly at 0.36 and that's what the dish's f/D ratio is, then everything is good. If the f/D ratio is actually 0.39 or 0.40, then it means the scalar ring is not filtering / choking the entire surface of the dish's reflective area, but a smaller portion of it. Likely this would mean more susceptibility to terrestrial interference and/or less overall gain on weaker signals, correct?
As always, thanks guys
sgs
Staff member
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Sometimes a thread gets so many posts in it that is can cause issues for the server so that why today we introduce The Song Name Game Part 3!
So let the game continue!
The last song was added by Bobby who posted...
One Meat Ball - Andrews Sisters
CONTINUE ON AND HAVE FUN! WELCOME HOME TO SATELLITEGUYS.US!
Here are the original rules for the game as posted by WebbyDude back in 2006. http://www.satelliteguys.us/threads/68645-Song-Name-Game
Just name a song title and the band who performed it. The next person does the same thing, but needs to list a song title or band name which includes a word from the previous entry. Pick songs from any genre.
Example:
Long Live Rock and Roll -- Rainbow
Rainbow in the Dark -- Dio
Another example:
Ride the Lightning -- Metallica
Lightning Strikes -- Ozzy Osbourne
Get it?
An additional note: we all know that song titles, sometimes, use profane words. Because this is a family friendly website it is advised that you clean up that title up a bit. This is accomplished by using something like sh!t instead of the real word. Thanks....
So let the game continue!
The last song was added by Bobby who posted...
One Meat Ball - Andrews Sisters
CONTINUE ON AND HAVE FUN! WELCOME HOME TO SATELLITEGUYS.US!
Here are the original rules for the game as posted by WebbyDude back in 2006. http://www.satelliteguys.us/threads/68645-Song-Name-Game
Just name a song title and the band who performed it. The next person does the same thing, but needs to list a song title or band name which includes a word from the previous entry. Pick songs from any genre.
Example:
Long Live Rock and Roll -- Rainbow
Rainbow in the Dark -- Dio
Another example:
Ride the Lightning -- Metallica
Lightning Strikes -- Ozzy Osbourne
Get it?
An additional note: we all know that song titles, sometimes, use profane words. Because this is a family friendly website it is advised that you clean up that title up a bit. This is accomplished by using something like sh!t instead of the real word. Thanks....
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For quite a while now, people with a VIP211k have been losing their recordings on their activated external HDDs... even when there's nothing physically wrong with HDD. I believe this is an intentional and underhanded tactic that Dish is pulling in an attempt to force users away from the VIP211k.
They are obviously regretting that they ever let users have a "non-dvr" dvr in the first place. You would think they would be happy charging you a $40 one time fee... and then be happy letting the customer be the one responsible for HDD failures.
Dish clearly hates the 211k bitter-clingers. This recording deletion problem is intentional (IMO), and I think it is just one more tool that they are using. Hopper and a 2-year agreement... that's what they want you to have. Think about that... a 2-year agreement... with a company $30 Billion in debt (that's with a B). What happens when all that debt causes them to drop the channel that may have been your whole reason for having Dish in the first place? Guess who's stuck with a service that no longer suits their needs... for the remainder of the 2-year agreement.
On top of that, they don't want you to install it yourself. I purchased and installed all my equipment myself. That used to be common. Now, they lie to me and tell me that my dish must be updated to use a Hopper. Funny thing is... they don't even know what dish I have because they didn't install it, and I didn't tell them. If you ask what type of dish/LNBs the hopper needs... good luck getting an answer. All they know is that whatever you have needs to be upgraded by an installer.
It is quite apparent to me that they care much more about staying in their box, than they do working with the customer. That's too bad, because it hasn't always been that way. It's like they are totally unaware of the current business environment that they are trying to compete in.
I have been a customer since 2010. I will be cancelling my service before the next period. Yeah, I know, my $1,200 a year won't make a difference to them. It just seems like they have forgotten who needs who, especially when you consider the competition in today's streaming world. But hey, they will have succeed in forcing me off the 211k.
They are obviously regretting that they ever let users have a "non-dvr" dvr in the first place. You would think they would be happy charging you a $40 one time fee... and then be happy letting the customer be the one responsible for HDD failures.
Dish clearly hates the 211k bitter-clingers. This recording deletion problem is intentional (IMO), and I think it is just one more tool that they are using. Hopper and a 2-year agreement... that's what they want you to have. Think about that... a 2-year agreement... with a company $30 Billion in debt (that's with a B). What happens when all that debt causes them to drop the channel that may have been your whole reason for having Dish in the first place? Guess who's stuck with a service that no longer suits their needs... for the remainder of the 2-year agreement.
On top of that, they don't want you to install it yourself. I purchased and installed all my equipment myself. That used to be common. Now, they lie to me and tell me that my dish must be updated to use a Hopper. Funny thing is... they don't even know what dish I have because they didn't install it, and I didn't tell them. If you ask what type of dish/LNBs the hopper needs... good luck getting an answer. All they know is that whatever you have needs to be upgraded by an installer.
It is quite apparent to me that they care much more about staying in their box, than they do working with the customer. That's too bad, because it hasn't always been that way. It's like they are totally unaware of the current business environment that they are trying to compete in.
I have been a customer since 2010. I will be cancelling my service before the next period. Yeah, I know, my $1,200 a year won't make a difference to them. It just seems like they have forgotten who needs who, especially when you consider the competition in today's streaming world. But hey, they will have succeed in forcing me off the 211k.
168 Replies
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Has anyone subscribed to NBA League Pass for 2026-27 and try to link their account to NBA.com to stream League Pass? I purchased it for 2026-27, and when I linked, I got a message saying success, but then I receive an error that my linked subscription does not include the preseason games for NBA League Pass. Is that how it has always been? I know satellite doesn't have the preseason games on the NBA League Pass channels, but I thought that I was able to stream the preseason once I linked my account on NBA.com?
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Supporting Founder
Really excited for this season with Kentucky having a new coach and some really exciting recruits. Probably won't last long, but here's hoping this season is great.
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Nah, you just don't understand how ignore works, which is why you made your own NFL thread thinking there wasn't one
For some reason, the satelliteguys.us site is loading a lot slower than usual on both Chrome on my Asus laptop and Safari on my iPhone.
I'm also seeing longer appearances of the blue bar at the top and the "3 blue bars" loading symbol.
Is anyone else also having the same problem? Thanks in advance.
I'm also seeing longer appearances of the blue bar at the top and the "3 blue bars" loading symbol.
Is anyone else also having the same problem? Thanks in advance.
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Remember folks... just like DNS... its always Foxbat. 
WTF… …What the Foxbat!Remember folks... just like DNS... its always Foxbat.
S
wow what a kick in the balls!!! the wife blames you when things don't work now scott's blaming youWTF… …What the Foxbat!
I know. Here's what Scott has in store for me if I get out of line:wow what a kick in the balls!!! the wife blames you when things don't work now scott's blaming you
S
OMG to freaking funny
You're no fun.
I thought I would come here and find lots of complaints about the update to the dish anywhere mobile app, but am not seeing any. It used to look just like the desktop webpage. Now you can no longer filter by sports channels or movie channels. Plus that they made it look like a big button telephone and you see fewer channels in the screen which requires more scrolling. Yes I realize you can look at sports then select which sport you want to look at, I just liked being able to see all sporting events in the guide with all other channels being filtered out. Am I alone in the wilderness on this?
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Lifetime Supporter
Apple has finally released their Apple TV 4K with built-in Siri and a microphone so it can respond to your queries even if you don't have the remote. It also increases in price, to $299. I had been planning on updating my current Apple TV 4K streamers, but that's $600 for the two of them, and that's a pass at this point.
At $299, it had better come with 256 GB of Storage, Gigabit (or better) Ethernet, the latest HDMI tech and standards, and one year of free Apple One. But it probably won't…
At $299, it had better come with 256 GB of Storage, Gigabit (or better) Ethernet, the latest HDMI tech and standards, and one year of free Apple One. But it probably won't…
Apple TV 4K
Apple TV 4K. New Siri AI and hands-free control. Stunning picture and immersive HomePod surround sound. Works with your Apple and smart home devices.
www.apple.com
20 Replies
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298 views
S
. apple's been making money off of software and not hardware for a while
they all do that anyways.. ever notice your cell phone slows down when you come up for an upgrade..
. apple's been making money off of software and not hardware for a while
You should have looked in the APP STORE instead.
Supporting Founder
Several Dish offers showed up today in my account. Once you choose one the rest are removed. Offers were Showtime, Starz, AMC and others.
35 Replies
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1684 views
Not for me, mines has no mention of how long aka the offer period and the Terms and conditions the $0.00 is good for. All I see is one can lose $5.00 if you decide to remove it before day 31 after you add it to the account.
You have a different offer that is free for a shorter timeframe which is different than the one that I and bnewt saw without defining the promotion period as I sent the question to DISH Care via Facebook Messenger and this is the response I got back 20 minutes ago.
TWiT Tech Podcast Network
Time for another AWESOME video from the TWIT Network!
View: https://www.youtube.com/watch?v=Y4Edq2eavsQ
Direct YouTube Link - This Week in Space 232
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View: https://www.youtube.com/watch?v=Y4Edq2eavsQ
Direct YouTube Link - This Week in Space 232
TWIT's Website
TWIT Live Feed
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TWiT Tech Podcast Network
Time for another AWESOME video from the TWIT Network!
View: https://www.youtube.com/shorts/oRVxjGm0qtE
Direct YouTube Link - Tim Cook, Elton John & King Charles: A Royal Tech Event
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View: https://www.youtube.com/shorts/oRVxjGm0qtE
Direct YouTube Link - Tim Cook, Elton John & King Charles: A Royal Tech Event
TWIT's Website
TWIT Live Feed
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