first post long time C bander

[gpat]

Ive had C band since the pre VC days(true FTA back then).
Now Iv e finally got into the 20th century and picked up a used
Chapparal corotor that was minus the Ku LNb,bought a used norsat
4000a Ku LNB and today tried to tune it in.
My old Channelmaster 8ft is getting tired,rusty mounts and pivot
but when aimed right it would pull in 100s in C band.
Im guessing that the mess is too large(5mm holes) so I picked up
a free Channelmaster 10 ft with c band LNB and the mount.
I was all excited about the freebie being a Channelmaster and figured I would keep the same mount and just swap dishes.
Well guess they didnt think the 8 ft was a good design and cheaped out on me with the 10 ft.
My 8 ft has a 3.5 inch pipe 10 ft in the ground and 6 foot out with the mount being a 5 ft x 4inch pipe.
Now I need to figure out how to use the 3.5 inch pipe for the 10ft as it has a 3 inch pipe in the ground and a mount that goes over that.
I may have to slide the 3 inch pipe into the old pipe and weld it to it.
Or if anyone had any suggestions Im all ears.
My receivers are several analogs(even have some manual tunes),a GI
home concepts,and a DSR 920 4DTV.
Ive tried to tune in some Ku's but so far no luck.
In thinking I got a bum used Norsat but wont call it that until I get the 10 ft up and running.

 

[dfergie]

Moved to C band... Welcome to SatelliteGuys! C-Band before VCII myself...

 

[gabshere]

Welcome to the group

yeah you can insert the 3 inch pipe into the 3 1/2 and double bolt it or even weld it.


pictures are nice also we have a whole section "c-band"

bunch of c-banders here and lots of tuning information

tuning is kinda an art lol its easy to hit c-band side but it gets harder trying to get ku and then to find the place inbetween where both signals are optimal.

a GI Home Concepts thats was a rebranded GI 350I or 450I right

we tend to walk all the way through setup when fixing up a c-band dish to receive ku. for one thing most were just setup for c-band and not ku . like mentioned earlier its easy to hit c-band. and some of the focal distance are off just a bit or even over the years a dish has gotten outa shape. we usually string it to check the shape and make sure the string is touching in the center. this also provides the distances to check the focal distance ( mainly to verify)

another thing to add in the future is a dvb receiver .

 

[gpat]

Welcome to the group

thanks

another thing to add in the future is a dvb receiver .

already ordered a Coolsat 6100
hope its ok as I didnt even consider the 7000

 

[gabshere]

yeah that should work great i have the coolsat 5000 and like it.

 

[truckracer]

Welcome to satelliteguys. You will love the coolsat FTA box.....Lots of digital stuff up there.

 

[gpat]

thanks guys
is that a GTO in your avatar

 

[sally01]

ive also been watching c band since vc2 days and wont give up my big dish till they remove hbo as i love those stations,and its mostly all i need.its sad we lost so many buds to the people hacking the direct tv when it was in full swing and now the hacking of fta,cant say i havent experimented with it myself but ive always maintained my subscriptions with my big bud so i cant say i really stole anything as i usually only watched the chanels i subscribed to as they are the only ones that interest me

 

[gpat]

Well moving on to bigger and better (I hope) things.
I replaced my tired old ChannelMaster 8.5 dish which is built like a battleship
and has served me well for over 20yrs.
I got another ChannelMaster 10 ft mesh dish with smaller mesh so hopefully Ill have success
converting it to C/Ku.
I set the 10 ft up and tuned it with the old LNB and feedhorn but went to swap it out with a C/Ku Corotor and found out the old Chaparral has the scalar ring as part of the feedhorn.
So I had to remove the old feedhorn assembly and replace the scalar ring with the Corotor
one.
Im not sure if I got the focal distance set right,I always thought you measured from the back of the throat on the feedhorn.
In this case theres 3/4" difference between the 2. So I set the co rotor up with the same distance on the front as the old one piece Chaparral.
I squared up the feedhorn in the scalar ring(see pic) and also took a pic of the focal depth
setting once installed.
Ive tuned it in pretty good but still dont get any Ku signals.
Since I cant validate the used Ku LNB I got Im still shooting in the dark.
Perhaps some one has some suggestions as to what I can do to improve my chances of Ku reception.

 

[harrysundown]

Mine is setup the same as yours and I dont get Ku I will be watching your thread for help.

 

[gabshere]

ok both of you can do this

string it all the way across two different ways , the strings should touch in the center of the dish.
and measure the distance from the center of the dish to the feedhorn
also get the measurment from the side to side
and get the measurment from where the strings touch to the center of the dish

this will get you ready to set the focal distance

we will let linuxman tell you how to adjust the corotor for skew settings but will need these numbers.

i can tell you how i search for ku on my bsc621 but its slightly different.

 

[gpat]

OK heres the poop on the dish
10'1" diameter
48"scalar ring to inside of dish
18" from strings to inside of dish(arc)
strings are dead on and intersect in middle
touch each other in middle and neither holds the other away.
I have the feed horn protruding 5/8 inch from scalar ring.
This is the same as the old Chapparal one piece feedhorn/scalar ring.

Ive also devised an alignment fixture jig that will hold the feedhorn straight
and centered when repositioning
Pics will follow

 

[gpat]

Pics of my "invention" feedhorn alignment jig.

Digital level is awesome

 

[linuxman]

OK heres the poop on the dish
10'1" diameter
48"scalar ring to inside of dish
18" from strings to inside of dish(arc)

You can calculate the proper F/D ratio which is the little lines on the sides of the co-rotor and the Focal Length at this site.

You can convert the inches to cm that you will need for the above site here. Edit: You may not be able to go by your old feed-horn because of the differences in length of the Co-rotor and your old one.

Once you have that, go here to get your Elevation and Declination settings for your area. You will have to look up your longitude and latitude, and put them in the way the examples show.

Then take a flat piece of steel to lay across the elevation bar and put a protractor with a string and a fishing sinker hanging from it and get your exact elevation, then lay the same piece across the back of the mounting ring to get the total angle of the dish. Then set the declination to however many degrees of difference the site above calls for.

Tighten that down and don't touch it again.

Adjust your F/D ratio to what the site calls for, then the Focal distance to the calculated length on the same site.

Find your True South Satellite and adjust the elevation bolt while on your True South Satellite for best digital C-Band signal, then setup the Ku satellite in your digital receiver CS 6000 I think you mentioned.

You should be able to find a Ku signal of some kind. Take a look at Icebergs list of strong signals in the FTA area.

Once you have a ku signal coming in, then adjust the elevation further until the Ku is zeroed in.

Once you have all that done, report back here with the results and we can go further.

Hope that helps,

Fred

 

[gpat]

Thanks for the info
You might be able to see the digital level i use to set up.
this dish was moved from a location about 20 miles SW of me
so I left the angle alone and it works great.
Im pulling in 64-72 on most sats and digital I get 99 on alot of channels.
Im still getting nothing on Ku so Im thinking its the used LNB.
I have a DSR 920 and a new CS 6100 which I havent yet figured out
how to hookup.
I may have a bad splitter because when I hook up the C band LNB to the
920 and the diseq switch I get nothing to the 920.
I havent yet powered up the 6100,dont want to until I get the wiring figured out.
My old ChannelMaster 8.5ft is sitting next to the "new" 10ft ready to pinch hit if needed.

I just rechecked the FD (set @36)and the antenna depth which was incorrect earlier.
The true depth is 1/2" deeper as the center has a bump thats not even with the mesh.

 

[somery]

harrysundown: what are the brand name and specs of your ku lnb? how old is the ku lnb? do you have another to test in its place? did you try swapping the cable from the cband lnb over to the ku lnb, and on the back of the reciever as well? I heard somewhere that those ku lnbs can die as early as 3 years.

 

[linuxman]

this dish was moved from a location about 20 miles SW of me
so I left the angle alone and it works great.

The digital angle finder should work ok, but I wouldn't trust the original installer to have it set for Ku properly.

To get the Ku signal the dish has to have the declination and elevation set almost perfectly.

Also the F/D and Focal Length sometimes isn't where it is calculated to be. I set the F/D ratio and start with co-rotor/scalar ring assembly at it farthest point and move the whole assembly towards the dish 1/4" at a time until I find it. If that is off, sometimes you won't be able to get much Ku signal either.

Fred

 

[gpat]

Heres what I got off site to try and aim it.



Latitude = 28.6771, Longitude = -81.2036 ​

Lat = 28 degrees, 40.6 minutes North​

Long = 81 degrees, 12.2 minutes West ​

Pointing a satellite TV dish at the Satellite at 79 West orbit longitude
​

Dish elevation= 56.4, Azimuth= 179.7 (magnetic compass), Polarisation= -4.0
​

Polar mounts only: Main angle= 29.3, Downward tilt= 4.2, Motor drive sideways angle= 2.5
And BTW thanks for help




Closest "south" sat is at 79*



The total angle on mine is 33.1*
as far as I can tell whats needed is 33.5*if you added the main angle
(mount angle) 29.3*,and the latitude adjustment of 4.2*.
It looks like mine is set at 27.3* on the main mount and 5.8* on the latitude
angle.
Is the sum total angle (33.5*)all thats needed to be right on or are both
the main and dish angles needed to be dead on?

​

 

[linuxman]

The total angle on mine is 33.1*
as far as I can tell whats needed is 33.5*if you added the main angle
(mount angle) 29.3*,and the latitude adjustment of 4.2*.
It looks like mine is set at 27.3* on the main mount and 5.8* on the latitude
angle.
Is the sum total angle (33.5*)all thats needed to be right on or are both
the main and dish angles needed to be dead on?

I plugged in your co-ordinates into the site I referenced, and got this information.

The offset that the site refers to is the declination which for you is 4.16 degrees.

So the way I would do it is to measure whatever angle you currently have on the main adjustment bar, and add or subtract from the measurement taken from the back of the dish, (mounting ring, back of center plate, etc) so that it comes out to 4.16 degrees difference.

The total angle is the sum of the two parts.

29.3 degrees main elevation adjustment
plus 4.16
=33.46

What will be actually measured will vary because of the differences in plumb, dish sag, etc.

But if you just leave the main elevation alone, and set the declination, then get your C-Band signal at it's peak using the main elevation adjustment, then you can try a Ku signal.

Fred

 

[gpat]

Fred,While you were typing this I went ahead and re adjusted this.
Looks like it was set for a latitude of about 38 not 28.
Now I have it dead nuts on at 4.2* and 29.3* for a total of 33.5*
Im going to now start all over with the "tune"
you were right assume means a** of you and me.
Im just thankful it still had the sticker on the side of the adjustment
showing what marks are for what latitude.
I would be there a long time trying to zero it in.
Going back out with fingers crossed.
thank so much