F/D Ratio .278 LBN Seeking

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Robert_W;
Take Pendragon's advice on the lnb, way easier for a 1st time setup.

Like Ku, try to hit just one bird like 99W for the networks first, just to check out the equipment, get used to adjusting the lnb, etc.

As for the jack and the mesh, if the mesh is ripped and dented, don't worry too much either for the 1st dish. A good, sturdy, perfectly plumb post can host another, better dish later on....

If the jack moves with a car battery, it can probably be restored. Rebuild it before running it a lot. Many threads here for that. The Gbox from Sadoun rocks for moving a BUD.
 
After looking at your feed pictures, I'd really recommend tossing it and starting with something else. It appears you have a LNA instead of LNB with an inline downconverter to 70 MHz. That's not going to work with any FTA gear capable of DVB or DVB-S2. It also looks like the f/D is set wrong on the feed itself. The rotor will be an issue even if it works.

A feed like the DMX you mentioned, a Geosat or even a BSC would get you started with a minimal investment. A lot of people here swear by them. My primary concern would be getting something where the feedhorn mouth can be set to project beyond the scalar rings by about 1.4" (this is the f/D setting), and still allow you to move the whole assembly in and out to get to the correct focal distance (which will probably end up 1/8 to 1/2" inside the feed). This might require some ingenuity with either or both of the scalar rings and/or your buttonhook. Failing to get this correct will cause the feed to 'see' only the center part of your dish, which would be a waste of a 10'. For example setting the feed's f/D to 0.3 instead of 0.278 will give you a loss of around 0.7 dB, which is the equivalent of using only a 9' dish instead of a 10'.

If you want to go all the way, a single ortho feed plus separate LNBs should get you the best signal. How much better I cannot say. I'm using mostly single ortho Chaparral feeds that cost around $60 and Norsat 8115s that are about $100 apiece. Going that path also means you would have switching and powering issues to solve. In addition this feed cannot do a f/D of 0.278 out of the box. Although a hacksaw can cure that problem, I'm still suggesting an integrated feed approach to start.
 
Notice the Dish Mover housing was rusted up at the throat of the shaft,,, might think of investing in a new actuator,,, but is there any that run off the new recievers? Or are they all analog?

A GBOX should run old and new actuators just fine. Best to get a 36V actuator.
 
yeah, I thought it might not be good to continue with same set-up. I wonder if I was to cut the weld on the buttonhook, and extend the buttonhook out from reflector. I wonder if this would help or move it closer into the reflector.
Or I can hack at the ribs, and flatten the dish to make it work?
I really do not know which way to go>
 
yeah, I thought it might not be good to continue with same set-up. I wonder if I was to cut the weld on the buttonhook, and extend the buttonhook out from reflector. I wonder if this would help or move it closer into the reflector.
Or I can hack at the ribs, and flatten the dish to make it work?
I really do not know which way to go>

My Winegard doesn't have a buttonhook, so I'm not familiar with the mechanical aspects of what you are dealing with. If you set the scalar ring as shown in the attached diagram, do you have a problem with the feed mouth being too close to the dish center, or too far? Whatever you do don't hack the ribs or flatten the reflector.
 

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  • Scalar f:D alignment.pdf
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the buttonhook is a j-rod. it extends from the core of the dish straight out then j's. this one is welded to it's lenghth of 33-5/15, looking diriectly into the center of the dish.
So I would have to set the f/d of 28 of the tube of feed (i think) to be at my f/D.
I think to give it even more support, the brackets could be placed. but this j pipe seems to be a sch 40 or 80 pipe used.
I will take a picture of it tommorrow to show you what it is. Plus it canrotate for a degree setting needed,,, I do not know but if I use a 20 degree lnb I would have to turn this pipe to have the degree needed.

Edit:
I do not have it up yet. I was concerned about this lnb,,,, or as you said "LNA". That is one reason why I did not get it all hooked up.
once get this cleared,,,, I just need to buy the LNB, and the wire, Then get my ground work going.
 
I'll wait for the pictures tomorrow, but looking at my manual for the Pinnacle (I posted this in the FTA Manuals if it is of any help), it claims there is a U-bolt clamp on the backside of the dish that allows you to move the buttonhook assembly in and out. Does that give enough range of adjustment?
 
http://www.satelliteguys.us/fta-manuals/137668-winegard-10-foot-antenna-mount.html

Iceberg has specs,,,, and the next member has the whole instruction manual. (which includes the buttonhook) except on these instruction the buttonhook is secured via a clamp,,, this used unit was set and welded.
As far as the 1.4" so from the feed month to the center length has to be 33-5/16???

dfergie is the other member.
 
http://www.satelliteguys.us/fta-manuals/137668-winegard-10-foot-antenna-mount.html

Iceberg has specs,,,, and the next member has the whole instruction manual. (which includes the buttonhook) except on these instruction the buttonhook is secured via a clamp,,, this used unit was set and welded.
As far as the 1.4" so from the feed month to the center length has to be 33-5/16???

dfergie is the other member.

Only the moderators can post manuals so dfergie did it for me. Yes to your 33 5/16" question, but that's only a starting point. Don't be surprised if it works better a little closer.
 
LNB, Chaparral 20º
Well this is what I purchased. I do not know if there will be any wiring require,,, exception of the coax to run to receiver.


Chaparral PR1E Feed
This is the feed I also bought. And believe that the 20 degree (LNB above) just bolts onto this.

Now about my reiever:
WINEGARDRECEIVERBACK.jpg
 
I received this statement:
Robert you can't use that receiver .It is not a block receiver.You may have to send it all back or someone can give you a receiver .They are $20.00 on EBay
Now what is "Block Receiver"?
Does he mean a "G-box"? Because this Winegard is not going to work for anything?

You have a 70 mhz receiver.It is not 950-1450 mhz
 
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I recieved this statement about the "Winegard Receiver SC-7038S" It is a "LNA".
PICTURE POSTED IN "F/D RATIO .278 LNB SEEKING"
Robert you can't use that receiver .It is not a block receiver.You may have to send it all back or someone can give you a receiver .They are $20.00 on EBay
What is meant about "Block Receiver"?
And being LNA, this will not power the servo motor of today's LBN?
Will a G-box completely replace this reciever? To do all funtions, and run coax "RG6" straight into Coolsat 5000 Premier?

You have a 70 mhz receiver.It is not 950-1450 mhz
 
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Your feed has a LNA on it. It amplifies everything in C-band (3.7-4.2 GHz, probably), but does not convert the frequencies. The LNA is connected to another box that is a downconverter, which changes the desired frequency down to 70 MHz. This is sent through the coax to the Winegard receiver. I'm not terribly familiar with this scheme because it is no longer used in FTA applications, but I assume there is some means for the receiver to select the desired frequency at the downconverter.

Nowadays we use LNBs, which are like LNAs in that they amplify the signal spectrum (3.7-4.2 GHz for C-band), but also downconvert it to a lower frequency, which is normally 950-1450 MHz. This is called block conversion, and leads to the 'B' in the acronym. The advantage of this scheme is the full signal spectrum can be easily passed over a good length of RG-6 and the receiver(s) can pick out the signals they want. It isn't practical to do this at the original frequency (3.7-4.2 GHz), and the problem with downconverting it to a much lower frequency, like 70 MHz, is you can't send the full signal spectrum.

The long and short of this is the receiver has to be matched to what is sent down the cable to receive signals. Your feed is set up for 70 MHz, but your Coolsat is set up for 950-1450 MHz. They won't play as is. Your polarotor (on the feed) and actuator are designed to be controlled by a receiver like your Winegard. The Coolsat cannot do this. The GBOX comes into play because it can control your actuator and the GBOX can take commands from the Coolsat to do this. However current GBOXes cannot control the polarotor on your current feed.

There are several possible solutions, but the easiest is the best. Get a GBOX and a new C-band feed without a polarotor. The Geosatpro you mentioned is an integrated feed (LNB onboard) and is a good starting point. The Coolsat knows how to change polarity on the Geosatpro feed and it knows how to command the GBOX. The GBOX knows how to drive the actuator. The Coolsat is designed to accept the frequency range the Geosatpro LNB provides.

Your Winegard receiver is very close to a doorstop, and there is very little reason to try to integrate it into your system. At best it can only pick up analog channels and there is very little of that left. The Coolsat is a good starting receiver for the current state of FTA. Does this make sense?
 
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This is better discussed in the C-band subforum. I have replied to your thread "F/D Ratio .278 LBN Seeking" there with the appropriate answers.
 
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