Old 6' Winegard f/d setup Question

[crazyshaned]

Hey guys, I've been lurking here for a while now, I figured that it was time to join up and say hello!

I've been tinkering with FTA for a couple years, ku and Cband stuff. I really appreciate the advice and the good work you guys do.

I've come across something of an odd duck. It's an old Winegard 6' aluminum mesh dish. When I picked it up, it even had an old hand crank mover on it.

Anyway, I got it mounted and plumbed up, put a linear actuator on it that I control with a Diseqc box, and I swapped out the old lnb with a new Titanium Sat C/KU setup.

When I fit the new lnb, I tried to keep the positioning the same as the one I removed.

After several hours of blindscanning on my Linkbox 8000hd, I was able to find a few transponders, but no channels.

I then saw a post here where someone made a scalar from an old aluminum worklight reflector. I duplicated the design and was immediately able to pick up the Lesea feeds with 98s and 66q.

At this point I decided to calculate my f/d and see if my lnb placement was off.

My dish is 72" in diameter.
If I run a straightedge across it, it measures 16" deep from the center.

So, if I did this right, F= (72 ×72) / (16 × 16) or 20.25"

If F/d is really F / d or 20.25/72 I get .28125, did I do that correctly?

When I measured my current lnb placement, it was at 25" from the center of the dish.

I've tried moving the lnb closer to the center and I lost all channels. If I remove the worklight scalar, I lose all channels.

I've played with a conical and a flat scalar, but was not able to lock anything. As soon as I put the worklight scalar back on, boom! There's Lesea again.

I was really hoping to catch the Ion channels with this setup, is a 6' dish just too small?

Thanks guys,

Shane

 

[crazyshaned]

Also, the sky is wide open here. Not a tree or building in sight.

 

[Titanium]

Welcome to SatelliteGuys!

From your measurements, I confirm the calculation for the FL of 20.25" and a FD setting of .28115

I have never seen a mesh dish with this low of FL/FD, but I would assume that it would have been distributed with a matching feedhorn/scalar.

The combo C/KU LNBFs have very unpredictable performance that is highly dependent on the reflector FD and FL to present phased signals to both the C-band probes and the KU-band probes. The work light "cone" that you are mounting is likely helping with the feedhorn mismatch, but still is not optimizing for properly illuminating the complete reflector surface.

I would decide between C-band or KU-band usage and dedicate the reflector for one band. For C-band, you might try and locate a feedhorn that is designed for low FD/FL reflectors. For KU-band, the Invacom adjustable feedhorn/scalar with an Inverto Black Pro voltage switched LNB could be paired with this reflector.

99w reception of stronger transponders on an 1.8m dish is possible, but the hardware must be optimized to provide anything reliable. I would not recommend the combo C and KU LNBF for any undersized or odd FD/FL reflector designs. The combo C/KU LNBFs work best on full size reflectors with standard FD and FL settings.

 

[crazyshaned]

Thanks Mr. Titanium. Here is a picture of the dish.

 

[KE4EST]

Welcome to the site!!!
Titanium's advice is spot on, pick one band or the other. I would not try to use a C/Ku with that dish size.

 

[Magic Static]

The 10' Winegard Pinnacle has a FD of .278 They are perforated not mesh. I suspect the 6 footer may be perforated as well. The Pinnacle is a very stout dish

 

[crazyshaned]

My bad, I thought if it had holes in it, it was a mesh dish. That makes sense.

Is there some kind of rule of thumb regarding dish size and f/d? Like a bigger diameter dish usually has a smaller f/d?

I'm not sure how exactly to go about selecting a lnb that's optimized for my f/d.

I wanted to use this dish for C band, the only reason I got a combo lnb was to aid in pointing the thing.

I do have the lnb that came with it. It's an old polorotor setup, but my receiver does not have provisions for polorotor control. It has a flat scalar on it, (well, more like part of it, its neither adjustable nor removable)

Can you guys recommend a C band lnb for my application?

Thanks again,

Shane

 

[FTA4PA]

I wanted to use this dish for C band, the only reason I got a combo lnb was to aid in pointing the thing. I do have the lnb that came with it. It's an old polorotor setup, but my receiver does not have provisions for polorotor control. It has a flat scalar on it, (well, more like part of it, its neither adjustable nor removable)
Can you guys recommend a C band lnb for my application?

Welcome to Satellite Guys crazyshaned. For a c band setup I would recommend the Titanium C1PLL.

 

[RT-Cat]

.....For a c band setup I would recommend the Titanium C1PLL.

I agree. I have two of them on my two 10 footers. They work very well.
And another big welcome to the best place on Earth to find and receive the best FTA information.

 

[crazyshaned]

Hey thanks again guys, I ordered up a C1PLL. I'll report back with my findings.


-Shane

 

[. Raine]

Welcome to SatGuys!

Sounds like your old feed may be a ADL, a C1PLL is a good replacement. I have a few here, they work great and the price doesn't break the bank!

 

[Shicks4]

My bad, I thought if it had holes in it, it was a mesh dish. That makes sense.

Is there some kind of rule of thumb regarding dish size and f/d? Like a bigger diameter dish usually has a smaller f/d?

I'm not sure how exactly to go about selecting a lnb that's optimized for my f/d.

I wanted to use this dish for C band, the only reason I got a combo lnb was to aid in pointing the thing.

I do have the lnb that came with it. It's an old polorotor setup, but my receiver does not have provisions for polorotor control. It has a flat scalar on it, (well, more like part of it, its neither adjustable nor removable)

Can you guys recommend a C band lnb for my application?

Thanks again,

Shane

Speaking of the polorotor you are talking about I have 2 chaparral polorotors right now. One i salvaged off an old dish about a year and a half ago that was more or less garbage and one that came on the dish i Just moved and set up. I ordered a C1PLL to put on the 10' i just set up but aperently there is an issue with the electronics on it. But i removed the lnb from the scalar ring for the C1PLL and wanted to see if i had a good lnb on one of the old polarotors and just jamed the thing into the scalar ring for the C1PLL. Obviously i was way out of whack on focal length but i was getting a 97% signal and 55%Q with my meter with this setup. SO next thing i did was looked at the 2 polarotors i had and choose the most weathered one I had and cut/ground the scalar off the feedhorn so it would now fit in the C1PLL scalar. Still have no way to control polarity (maybe but that is another experiment) but i was finally able to at least do some tweeking to my dish last night with only horizontal polarity, and i still have one good polorrotor and one for experimentation. But from everything I have read the C1PLL is the goto for c-band lnbf, unless you have the setup and cash for some decent lnb for a polorotor.