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Old 24-05-2011, 17:43
ACU
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I currently have a sky box, from which I get a couple of mixes, sky sports and HD channels. I bought a tv (Panasonic PZ81B) with a freesat tuner built in. I ran an additional cable from my sky dish, to my tv.

All was working fine for over a year. Now all of a sudden, when I switch to the freesat feed, I get a "No Signal" message. I have tried re-tuning the channels, and this completes in around 30 seconds (I could have sworn this used to take longer), reporting that it has found around 100+ channels, and around 30 radio channels. The signal strength (when retuning) is around 7/10, the signal quality is slightly higher, 8/10.

Anybody have any ideas?
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Old 24-05-2011, 18:00
grahamlthompson
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At a guess for some reason you have lost access to some transponders most likely including the freesat home transponder on Eurobird 1. (11428 H).

Possible reasons

Failed lnb
Dish Moved
Water in the coax cables
Interference from a local rf source (Wifi Router/Dect Phone)

Current Freesat total depending on post code is around 170 (Radio + TV)

Another possibility is a faulty power supply from the Sky box screwing up the lnb (Try turning off the Sky box at the mains) to see if you get back your freesat ones.
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Old 24-05-2011, 18:17
Masteriser
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Another possibility is a faulty power supply from the Sky box screwing up the lnb (Try turning off the Sky box at the mains) to see if you get back your freesat ones.
I agree with Graham. If your Sky Box is a Thomson these are notorious for their failing Power Supplies. One of the symptoms is interferance caused to other units sharing an LNB (the LNB on the dish is powered by the box and if the power supply is failing is sends all sorts of noise and other crap up the line to the LNB along with the power. This noise is what causes the interferance. Given time (probably not very much) the noise will affect the Thomson HD box too. Of course if your HD box is not a Thomson please disregard all of the above.

However, if it is and you want to repair it (properly repaired Thomsons are usually pretty soild boxes but you should know that they will not be getting any new software updates so no Anytime+) your repair options are here.

I upgraded my Thomson's Power Supply over three years ago and have never looked back such was the improvement in reliability. Anytime+ does not excite me so I am happy to continue using it for the forseeable future.
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Old 25-05-2011, 11:04
ACU
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Thanks for the replies.

The cable I ran from the dish goes directly to the tv (the tv has a built in freesat HD tuner), it does not go through my sky box. I have an additional two cables from the dish that go into my sky box. This provides my sky channels.

I doubt the dish has moved, as I still get my sky channels. The sky side of things still works fine. Its just the freesat service that I am having problems with.

I will check the connection to the dish, and make sure that is ok. Thanks for the info on the transponder name, grahamlthompson. I will check this. Is there any reason why I should all of a sudden lose access to this transponder?
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Old 25-05-2011, 11:08
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Yeah - you miss the point. What he's saying is that the Sky box could be sending interference up its cables, and this is confusing the LNB at the dish and causing it to send interference down the Freesat cables. I don't know the technical reasons why this would happen (it seems pretty unlikely to me), but that's essentially what he's suggesting AFAICT.
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Old 25-05-2011, 12:08
grahamlthompson
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Yeah - you miss the point. What he's saying is that the Sky box could be sending interference up its cables, and this is confusing the LNB at the dish and causing it to send interference down the Freesat cables. I don't know the technical reasons why this would happen (it seems pretty unlikely to me), but that's essentially what he's suggesting AFAICT.
It's a common fault as already said with Thomson sky boxes.

Instead of outputting pure dc it has an imposed ac ripple (dirty DC) which upsets the lnb (in addition to the designed 22Khz band switching tone.). First symptoms confusingly affect other equipment rather than the actual Sky box. It's easy to check just power down the Sky box as originally posted. This will leave only the freesat tuner providing lnb power.

Freesat boxes rely heavily on access to EB1 where Sky boxes do not. The OP's inability to get the full Freesat channel line up could well be down to dish alignment most possibly lnb skew which has to be a comprimise between the setting required for Astra 2 and that required for EB1.

Look at the first Q and A here

http://www.satcure.co.uk/tech/thom_psu.htm
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Old 25-05-2011, 16:23
ProDave
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As others, I strongly suspect a sky box problem.

Unplug your sky box from the mains and see if your freesat reception on the tv improves.
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Old 25-05-2011, 16:43
ACU
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Yeah - you miss the point. What he's saying is that the Sky box could be sending interference up its cables, and this is confusing the LNB at the dish and causing it to send interference down the Freesat cables. I don't know the technical reasons why this would happen (it seems pretty unlikely to me), but that's essentially what he's suggesting AFAICT.
Ah ok, I see what they were saying. I will give this a try, when I get home this evening and see if turning of the sky box helps.

Thanks for the link grahamlthompson. I will have a read.
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Old 25-05-2011, 19:02
ProDave
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Ah ok, I see what they were saying. I will give this a try, when I get home this evening and see if turning of the sky box helps.
Make sure you unplug the sky box from the mains.

"turning it off" usually just means putting it into standby, in which case it is still powering the LNB and will still interfere with other boxes if it's faulty.
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Old 26-05-2011, 11:27
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I tried this yesterday. Unplugged the sky box from the mains (physically took out the plug from the socket, as suggested), and re-scanned for the freesat channels. It managed to pick up the channels, however when you select a channel it still said "No signal" The guide worked, and you could see what was on and get info on a program. I just couldnt get a picture or sound.
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Old 26-05-2011, 11:37
grahamlthompson
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I tried this yesterday. Unplugged the sky box from the mains (physically took out the plug from the socket, as suggested), and re-scanned for the freesat channels. It managed to pick up the channels, however when you select a channel it still said "No signal" The guide worked, and you could see what was on and get info on a program. I just couldnt get a picture or sound.
Is that all channels or just specific ones ?
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Old 27-05-2011, 14:26
ACU
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Is that all channels or just specific ones ?
I get a "no signal" on the first 7/8 channels, I didnt bother going further. The guide works for all channels, well I assume so, I was getting listing for the first 20 odd channels, didnt bother checking the rest.

The fact that I get listings info, does this mean that the freesat tuner, dish alignment are ok?
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Old 27-05-2011, 14:30
ProDave
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Are ALL channels working okay on your sky box?

If so, try physically taking the freesat tv to the room where the sky box is, and plug it into one of the feeds used for the sky box. See if it receives all channels there?

If it does, then you have a problem with the cable you installed, a kink perhaps, or water ingress in the cable?

Could also be a faulty output on the LNB. By my reckoning, 2 are used for the sky box, and one for the freesat tv, so try moving the cable for the freesat tv to the currently spare LNB output.

You did wrap the F plug and cable in self amalgamating tape didn't you?
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Old 27-05-2011, 14:38
grahamlthompson
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I get a "no signal" on the first 7/8 channels, I didnt bother going further. The guide works for all channels, well I assume so, I was getting listing for the first 20 odd channels, didnt bother checking the rest.

The fact that I get listings info, does this mean that the freesat tuner, dish alignment are ok?
No it just means you can get a signal from the freesat home transponder (11427 H Eurobird 1), this is where you get the epg data from.

Not familiar with your TV but if it has a manual tune option that lets you check specific transponders, get the current freesat transponder list from here

http://humaxgoodies.weebly.com/frees...ansponder.html

Check the transponders in turn and look to see if there's a pattern (The list has transponder frequency and polarisation and which satellite it's from)
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Old 27-05-2011, 15:32
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Are ALL channels working okay on your sky box?

If so, try physically taking the freesat tv to the room where the sky box is, and plug it into one of the feeds used for the sky box. See if it receives all channels there?

If it does, then you have a problem with the cable you installed, a kink perhaps, or water ingress in the cable?

Could also be a faulty output on the LNB. By my reckoning, 2 are used for the sky box, and one for the freesat tv, so try moving the cable for the freesat tv to the currently spare LNB output.

You did wrap the F plug and cable in self amalgamating tape didn't you?
Sky is working fine, no problems at all with sky. I had thought about swapping the cables around, but was hoping I wouldnt have to...not that easy. It looks like I may have to do this, and see what happens. If swapping the cables works then I will move the freesat cable to the currently spare LNB.

Yes, I did use amalgamating tape.

No it just means you can get a signal from the freesat home transponder (11427 H Eurobird 1), this is where you get the epg data from.

Not familiar with your TV but if it has a manual tune option that lets you check specific transponders, get the current freesat transponder list from here

http://humaxgoodies.weebly.com/frees...ansponder.html

Check the transponders in turn and look to see if there's a pattern (The list has transponder frequency and polarisation and which satellite it's from)
I did see any option for switching satellites...Will give this a try. I tried the link, but clicking on the file on the page, gives an error. I take it the excel spreadsheets show the same info (I am able to download those)?

Thanks to both of you for your help, its appreciated.
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Old 27-05-2011, 15:43
grahamlthompson
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Turn off the Sky box at the mains switch (Is it by any chance a Thomson box ?). Do you get your freesat channels back ?
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Old 27-05-2011, 15:48
grahamlthompson
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Sky is working fine, no problems at all with sky. I had thought about swapping the cables around, but was hoping I wouldnt have to...not that easy. It looks like I may have to do this, and see what happens. If swapping the cables works then I will move the freesat cable to the currently spare LNB.

Yes, I did use amalgamating tape.



I did see any option for switching satellites...Will give this a try. I tried the link, but clicking on the file on the page, gives an error. I take it the excel spreadsheets show the same info (I am able to download those)?

Thanks to both of you for your help, its appreciated.
The one spreadsheet does, the other is a macro driven Excel application designed for Foxsat-hdrs to identify which channel combinations are recordable and viewable using one or two cables. You don't need to change satellites the box assumes all the satellites at 28.2/28.5E are the same one. The transponder details identifies which of the 4 currently in use it comes from. Eurobird 1 at 28.5E and Astra 2A 2B 2D at 28.2E, shortly to be joined by a 5th - Astra 1N.
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Old 27-05-2011, 15:59
ACU
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Turn off the Sky box at the mains switch (Is it by any chance a Thomson box ?). Do you get your freesat channels back ?
I have tried this, and it didnt help. I have a samsung HD box.
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Old 27-05-2011, 16:12
grahamlthompson
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I have tried this, and it didnt help. I have a samsung HD box.
Long shot. I have fixed the link for the .htm file
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Old 27-05-2011, 16:16
ACU
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Long shot. I have fixed the link for the .htm file
Thanks. Will check when I get home.
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Old 27-05-2011, 22:48
SWIZZ?
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Instead of outputting pure dc it has an imposed ac ripple (dirty DC) which upsets the lnb (in addition to the designed 22Khz band switching tone.). First symptoms confusingly affect other equipment rather than the actual Sky box.
Does this satisfy the criteria that would cause a Murdoch to be transported to Oz ?
16 of them went that way in the 1800s

David
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Old 27-05-2011, 23:32
grahamlthompson
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Does this satisfy the criteria that would cause a Murdoch to be transported to Oz ?
16 of them went that way in the 1800s

David
IF ONLY

A certain Alan Bond springs to mind
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Old 28-05-2011, 16:42
Hollo and Gonch
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I have a similar (but much less extreme) problem.

I have always had a "no signal" message on a few minor channels, such as JML Direct... and now, very annoyingly, I get it on Channel 4 HD.

I have a cheapo Bush Freesat HD box, and I live in a block of flats with a shared dish. The signal strength/quality on most of the channels is very good.

Does anyone else have an issue with "no signal" on a few random channels?
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Old 28-05-2011, 17:08
Muzer
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Channel 4 HD, as well as a few other Eurobird transponders, can suffer interference from some reasonably close satellites, so if your dish is not quite aligned correctly, it can be the cause. There could be other causes too, though, so if your dish is hard to get to, I would put it off until you've tried some other things I'm sure other people will suggest.
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Old 28-05-2011, 17:44
grahamlthompson
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I have a similar (but much less extreme) problem.

I have always had a "no signal" message on a few minor channels, such as JML Direct... and now, very annoyingly, I get it on Channel 4 HD.

I have a cheapo Bush Freesat HD box, and I live in a block of flats with a shared dish. The signal strength/quality on most of the channels is very good.

Does anyone else have an issue with "no signal" on a few random channels?
Are they truly random or all using a similar transponder frequency. Loss of a few transponders could be down to a local rf source. Try switching of wifi routers and cordless phones. Of course a source could be a neighbours kit.

Here's a handy tool to see just what wifi network signals you may have where you are.

http://www.metageek.net/products/inssider/

However I think CH4-HD could be missing because it's a DVB-S2 channel. Some Harvard boxes are known not to work with DVB-S2, if yours is one of them your retailer should replace it under the SOGA regulations.
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