I pickup SBS channels but can't get Freeview?

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Carey

19 posts

Geek

#88474 17-Aug-2011 00:25

Hi all,

I've finally got my computer hooked up with a Hauppauge Nova-S USB2 device and I can pickup 7 SBS channels including SBS HD (using either WinTV or nPVR) with the following satellite settings:

Scan type: Single LNB
Optus D1 160E satellite
LOF1: 10750
Switch: 0
LOF2: 10750

I haven't managed to get up to the roof to check out the LNB info but I think the sat was installed in the last 3-5 years so I'm assuming it's dual LNB. I assume it is a SKY dish.

Is anyone able to tell me how I might get Freeview channels? Why can I only see the SBS ones, it's almost as if the device is looking on the Optus C1 but I've tried numerous times on D1.

Is there some scan software that I can use to do a blind scan?

Thanks,

Carey

1 | 2

1598 posts

Uber Geek
Inactive user

#507647 17-Aug-2011 00:32

Freeview|Satellite was down recently. There were a number of posts about it, have a search up the top.

dontpanic42

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+1 received by user: 11

#507771 17-Aug-2011 10:43

Keep in mind that Satellite Freeview is Horizontal polarization, and the SBS channels are Vertical polarization. You can only view one polarization at a time.

You say that you have a dual-lnb, do you also have two satellite coax cables/connections at your wall?

Carey

19 posts

Geek

#507847 17-Aug-2011 12:23

I'll try and get to the satellite to read the LNB details tonight, but it looks oval shaped from the ground. ?It only has one outlet at the wall, a typical tv reception connection (belling lee?).

How can I change to scan a horizontal pole? ?I've been using WinTV v7 and nPVR to scan, and nPVR appears to be scanning horizontal and vertical on the 22500 SR (which SHOULD get the NZ Freeview channels) and 11600 SR (which gets the SBS channels)...

I also can't get Win Media Centre to recognise my Nova-S USB2 tuner....

dontpanic42

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+1 received by user: 11

#507884 17-Aug-2011 13:10

Probably what you have is a standard 65cm sky dish. This dish will have a dual LNB of sorts.
I think the dual LNB (the oval one you have) on the sky dishes are used as more of a backup just in-case one satellite goes missing.

The main LNB inside the oval LNB is set to point at Optus D1, and if there is a problem with the sky feeds on D1, I think they can shift over to the other LNB which is slightly offset, therefore pointing at another satellite. Or at least I think that's how it works.

So even though you essentially have two LNBs, you are really only able to access one at a time. Actually, that may not entirely be true. You may be able to access the other side of the dual LNB using a 22KHz tone or similar, but it would be of no use because it will always be pointing at the wrong satellite. Freeview and SBS are on the same satellite, but on different polarities.

To further explain polarities.
Polarization is implemented to allow for more channels to be beamed down to earth. Most LNBs will allow for polarity switching, and this is done by feeding a different voltage from the satellite receiver to the LNB.
13volts for Vertical (SBS)
17volts for Horizontal (Freeview)

Polarity switching is actually a physical process (well, actually... semi-physical really) inside the LNB, so if the LNB is receiving 13volts, it will physically be in the Vertical position. If it is receiving 17volts it will physically be in the Horizontal position. If you start feeding two different voltages to one LNB, through one cable, that's when things start to not work.

Ultimately, with your current situation you can only watch/record either Freeview or SBS separately, but not both at the same time.

Carey

19 posts

Geek

#508103 17-Aug-2011 17:02

Thanks for that info! So to the crux of the issue then....Do I need to go up to the SKY dish and swap a power lead or a button or something to switch it to 17v supply?

Or will I need to get a new LNB?

I'm a bit surprised, as I am watching nPVR scan through the horiz polarity freq's but it's certainly not seeing them....

xarqi

727 posts

Ultimate Geek
+1 received by user: 7

#508108 17-Aug-2011 17:10

The receiver will send the appropriate voltage to the LNB depending on which service is being selected, and that will cause the LNB to switch to the required polarity. You should not need to (in fact it is not possible to) change anything on the LNB. Your issue has me puzzled, but I'm no expert so that's no big surprise.

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dontpanic42

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#508112 17-Aug-2011 17:17

It sounds like the LNB could be broken, and therefore stuck on vertical polarity. It can happen.
Your satellite tuner card will automatically provide the LNB with the correct voltage depending on the channel you are accessing.

To be sure, you could try testing the voltage that comes out of the tuner card with a multimeter to check that the tuner card is actually outputting the correct voltage. Or better yet, if you have access to another satellite receiver, hook it up and see if that can get freeview.

It could also be that there may be too much cable in the run up to the dish, which might be dropping the voltage too much. Or maybe the cable has become damaged recently. All possibilities, but the best thing to do would be to see if you can test with another receiver box/card, and check the voltage coming out of the satellite receiver.

:)

Carey

19 posts

Geek

#508146 17-Aug-2011 18:16

Thanks for the help. I've been up to check the dish - it's a Sharp Ku-LNBF dual dohickey, exactly like the example photo below.

If it was used for SKY channels, then I guess the horizontal polarity was working at some stage right?

I'll try beg borrow or steal a sky box.....or a Dick S. borrow ;-)

Carey

19 posts

Geek

#508149 17-Aug-2011 18:17

Make that a freeview box to get rather...

dontpanic42

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#508163 17-Aug-2011 18:32

If you figure out that first LNB is the problem, the other side of the LNB might still be alright.
If you feel adventurous enough, you might be able to shift the other side into the centre of the satellite and hook up the other side. Or if it doesn't have a second physical connection for the other side you may be able to access the other LNB with a tone or SR setting on your tuner.

openmedia

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Trusted

#508168 17-Aug-2011 18:44

I'd look at replacing the LNB. I've just moved house and the Sky Sharp Quad output LNB could do SBS but had major issues with freeview. I got a replacement bracket and LNB from freeviewshop.co.nz

Generally known online as OpenMedia, now working for Red Hat APAC as a Technology Evangelist and Portfolio Architect. Still playing with MythTV and digital media on the side.

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jellicoe

4 posts

Wannabe Geek

#508915 19-Aug-2011 11:33

I have the same problem

can only get TP 12648 Vertical

and no other TP's at all

is this fixible or to I need a new LNB unit?

Carey

19 posts

Geek

#509500 21-Aug-2011 00:27

Ok, just to update:

I picked up a freeview set top box, and tried that out but no luck - didn't even get the SBS channels that I could get on my computer, but the scanning only takes about 3 seconds so maybe something's amiss there?

So, STB failing, I got a new LNB and replaced the old sky one, just got my mate to keep clicking scan on the STB while I held the LNB in approximately the old LNB position. STILL no channels at all.

At this point, I'm flummoxed! This thorny little issue has destroyed my confidence in 'the simplicity of freeview and satellite dish's'.

I'm assuming that there's a problem with the cabling from my dish to my wall outlet, or it's something else that I've completely missed. Either way, I'm probably going to get an expert on to it.

....after I run a multimeter over the voltages in the cabling of course ;-)

cheers guys, any tips to add?

illicit

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Ultimate Geek
+1 received by user: 15

#509551 21-Aug-2011 10:46

Pay a professional for half an hour to check out if the LNB is working correctly.

$40ish = problem solving done.

Carey

19 posts

Geek

#510209 22-Aug-2011 22:59

Final Update:

Problem solved by a professional: cost=$50.

He brought around his own STB and it worked perfectly, with 80% min strength.

So the problem was.... Sommet Freeview STB from Dick Smith for $99. Piece of crap.
The technician said he'd seen a few of these lately, and one lady took hers back and was given another one that also didn't work. The one I got from DSE had been opened, so perhaps they're just handing on the returns grr.

The other problem for me is that the Hauppauge Nova-S USB2 tv tuner doesn't work properly. I can still pickup the SBS channels but no sign of the NZ freeview channels. So, only vertical polarity is working somehow.

Not sure if I want to try another one of these devices....I wonder if there's any better tv tuner cards for satellite?

Thanks for input guys

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