Adding DVB PC FTA to exisiting c-band BUD system

Northman · #1 (**permalink**) 07-06-2003, 04:23 PM

:?
Hi,
I have an old BUD 10' that I have only used for c-band analog channels(which I want to continue using). I have no idea if the feedhorn has spot to add Ku LNB. That 4DTV stuff is just way too expensive for me.

I would like to try and add a new DVB card like the Vision Plus to get the FTA channels and digital signals. I hope some one can help me to figure out what I would need to do to be able to do this.

Would I need a new feedhorn or just need to add a Ku LNB?
Does the cband cable carry the needed signal already?
What extra stuff if any would I require?
Could a direct TV or Bell LNB just be taped onto the existing feedhorn or is some special type of LNB needed?

Thanks

bobkat · #2 (**permalink**) 07-07-2003, 07:53 PM

What you will need is a dual feedhorn capable of mounting both a C-band LNB and a KU-band LNB. Chapparrel makes a nice one. You will need 2 coaxial cables, one from the C-band LNB and one from the KU-band LNB.

A DirecTV or ExpressVu LNB will not work for most FTA satellites; you will need a linear polarity type.

kat

Northman · #3 (**permalink**) 07-07-2003, 09:20 PM

:?
Thanks Bobkat.

Can you please tell me exactly what LNB I would require?

Apparently I bought an 11.7-12.2 GHz linear polarization with a 10.75 GHz local oscillator LNB from ebay. I was told that it was used for Bell ExpressVu and SkyVista when they were using a standard KU satellite and that its main value now is in MPEG2 DVB Free To Air digital TV, which they are hard to beat for the money since they are rated at .6db noise. I was told by the seller that it was a current Bell lnb, so at the time I was not too happy that I had bought it.

Do you think that this could be used with my big dish? If so, how could I tack this onto the BUD so that it will get a good signal?

I still will have to try and figure out which FTA PC card is the best.

Can these DVB cards really get Dish and Bell channels along with all of the FTA channels?

bobkat · #4 (**permalink**) 07-07-2003, 11:23 PM

The old linear LNBs for ExpressVu work really well on FTA -- I use them all the time with 30" dishes. The problem with using them on a B.U.D. is adjusting the skew. The advantage of using a KU band LNB made for a B.U.D. is the LNB is mounted on the feedhorn and the polarizer motor (used for the C-band LNB) now also controls skew for the KU LNB.

Some brands of KU LNBs made for B.U.D.s are Chapparel or Norsat or Aspen Eagle.

kat

Northman · #5 (**permalink**) 07-08-2003, 09:19 PM

ops:
OK, Now I have to ask what is probably a really dumb question.

What exactly is skew?
This is something on my old system that never seemed to do anything.
Adjusting the skew had no effect on my c-band reception.

Thanks

bobkat · #6 (**permalink**) 07-09-2003, 12:16 AM

Does your B.U.D. move or is it fixed? If its fixed then skew is something you probably never had to worry about as many fixed C-Band dishes had LNBs with electronic polarity control. Skew is the movement of the antenna in the waveguide (part of the feedhorn) that shifts 90 degrees to adjust between vertical and horizontal polarities depending on what channel you are tuned to. The C-Band birds typically had 24 transponders and as you change channels and thus change transponders the antenna must move to align itself with the changing polarity. The feedhorn assembly has a little blue motor on it that moves the antenna. This motor has 3 wires (red, white and black -- +5Vdc, pulse and ground) that are connected to the analog receiver and gets the control voltage and "shift" command from the "pulse" output on the receiver.

Adjusting the skew will have a noticeable effect on signal reception. If you never noticed any change then either your LNB was of the electronic switching variety or your polarity motor was not working right - in this case you would get signal on only odd or only even transponders. And as they say -- if you don't swing both ways you're missing half the action :lol: :lol: :lol:

kat

Northman · #7 (**permalink**) 07-09-2003, 08:58 PM

Hi Kat, Thanks again.
My BUD is moveable and not fixed. That is why I want to us it for one of these new DVB cards.

It does get 24 channels per sat and it does give even and odds. The skew buttons on the remote never seemed to do much to improve the picture and there is no display to tell what skew setting is. I think if you hold it down for a minute or two the picture messes up but I was never sure what it was doing and it never made the picture better.

My dish is a Global Image mesh can it get the Ku signals OK or would these signals just go right through it?

bobkat · #8 (**permalink**) 07-09-2003, 09:45 PM

Quote:

Originally Posted by Northman

. I think if you hold it down for a minute or two the picture messes up but I was never sure what it was doing and it never made the picture better.

My dish is a Global Image mesh can it get the Ku signals OK or would these signals just go right through it?

Your polarity motor is functioning properly - when the picture "messes up" that is a result of the motor changing to the opposite polarity of what is required.

I have heard that some mesh type BUDs have problems with reflecting KU band signals; I have done KU upgrades to several mesh BUDs and have had no problems. I guess its a matter of trying it with your dish.

kat

Northman · #9 (**permalink**) 07-11-2003, 05:00 PM

OK, Thanks. Now I will have to look at my dish and see if I just need to find a new Ku LNB or if I need a whole new feedhorn.

Northman · #10 (**permalink**) 07-26-2003, 05:02 PM

Hi,
I finally got a look at what my old c-band BUD has. Unfortunately it is just a c-band feedhorn not a dual one.

I did buy a nexus card and set it up to a small dish pointed to the Dishnet 110 sat and it works great! I still want to hook it up to my big dish.

The c-band LNB that I have is a Nexus NXB 435 35 degree K, 950 - 1450 MHz. Is this a good c-band LNB or are the newer ones better? Would it be worth replacing it with a newer one?

Could someone please tell me what would be the best Feedhorn and Ku LNB to get and how much of a cost would I be looking at?

Does anyone know of a good place to buy these items in the Edmonton AB area? I would prefer to buy from Canada to avoid all those extra problems and customs/broker costs.

Thanks

bobkat · #11 (**permalink**) 07-26-2003, 06:52 PM

Northman:

Check your PM Inbox for valuable info !!!!

:wink:

kat

Northman · #12 (**permalink**) 08-01-2003, 01:42 AM

Thanks Kat.

I have the parts that I need to get on order now. Getting a used feedhorn and new Ku LNB. Hope to have them soon.

I was thinking of splitting the signals from the BUD so that both PC DVB and other old reciever could work at the same time depending on what sat dish is being aimed at of course. What kind of splitters would I need to get to do this? I have a diseqc switch with 4 inputs that I got when I bought the DVB card.

Are there any instructions on how to adjust the new LNB/feedhorn? What satellite should I point to when I go to install the new equipment?

I think that all I need to do is point to a sat like G5 with my old system and then replace feedhorn turn old system back on and now I should get reception on old system and also new Ku signal for DVB. Is this correct or is there a lot more to installing a KU LNB?

Northman · #13 (**permalink**) 08-12-2003, 01:58 AM

I installed a used dual feedhorn and new Ku LNB. I tried hooking up c-band and Ku band to PC Nexus card to see if I could get any signal strength. Could this have fried part of receiver that controls Servo Motor?

The servo motor no longer works so I just get odd or even now.

I tried a brand new servo motor but it didn't work.

Does anyone know how to fix this sort of problem? Or know of someone in Edmonton area who can fix this sort of thing?

Is there some other unit that can be bought to just contol this servo motor?

Receiver is a Fujitsu FSR4500.

Thanks

Northman · #14 (**permalink**) 08-12-2003, 02:13 AM

I checked the voltages at back of receiver and there is constant 5V for the red wire but nothing on the white wire even when the changing channels or skewing.

Northman · #15 (**permalink**) 08-13-2003, 02:12 AM

I am getting 5 V on the back of the receiver for the red wire. The white wire Pulse voltage on the even channels shows 10 with multimeter at 2000 M and on the odd it changes to 6. Using the skew also makes the voltage change but the voltage is always small.

Does this mean the new servo motor I got is bad or is it the receiver? Are these voltages what they should be or are they too low?

Thanks

deadfly · #16 (**permalink**) 08-13-2003, 09:38 PM

I would double check the wiring going out the polorator motor before anything else. Make sure there is continuity through the wires and double check your crimp connections at the motor end.

The pulse wire unless I'm totally out to lunch here is the wire that brings back the signal from the motor on the feedhorn to let the receiver know how many turns have been made and where the wire in the feed horn is pointed. I think it's just a magnet that spins past a coil. Never ever took one apart though, so could be totally wrong.

Let us know if adding the Ku was worth the effort. I'm just running my DVB receiver off C-Band. Didn't seem to be enough English language programing on Ku to go to all the additional expense off buying a new dual band feed. Pansat has a Ku LNBF that is for a regular, non-offset dish that is not too expensive, but I'm not sure how good it would work duct taped to the old C-band feed horn.

Northman · #17 (**permalink**) 08-14-2003, 01:44 AM

Thanks deadfly. I tried hooking the new motor up directly to the back of the receiver to eliminate possible cable problems. It does nothing when changing the channels. Before it broke I could here the motor working with every channel change. I think the pulse voltage should go to at least 1 volt when changing channels. I will take receiver in to be repaired tomorrow.

What kind of channels can you get off of c-band? Can you get all of the digital channels? Can you get Dish and Bell? I have a nexus card but have yet to get any signal from my BUD when it was hooked up to it. Maybe I didn't need to get the Ku. All I have been able to watch on it so far are some little league baseball games on my old receiver. The improvement in my c-band picture was worth the $200 I spent on feedhorn and new LNB.

Once receiver is fixed I will try hooking the BUD signal wires up to my PC again but using splitter bypass switches this time.

Northman · #18 (**permalink**) 08-15-2003, 01:17 AM

Got my receiver fixed, Installed servo motor and it works great now!.

Now I will need to try and find some Ku channels and try and adjust it.
I tried moving the feedhorn in and out and rotating it but it makes no difference to the C-band signal strength.

Northman · #19 (**permalink**) 08-15-2003, 10:54 PM

Had to get receiver repaired. Works fine now.

deadfly · #20 (**permalink**) 08-16-2003, 12:09 PM

Lot's of FTA digital channels on C-Band. All the foreign language programing is on Ku, but most of the english language FTA programing is on C-Band. Bell is on Ku, but it's also not FTA so you need their system for that. The LNB is different again from a Ku lnb that you would have on a BUD.

Check out lyngsat for more details ...

http://www.lyngsat.com/freetv/North-America.shtml

The C-Band stations are coloured in pink. Anything with the video listed as DVB should be available.