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Old 10-03-2011, 16:41
beejay3
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On a French forum a contributor having problems with some freesat channels has revealed he has two dishes set to 28E one connected to LNB 1 and the other to LNB 2 inputs of his Freesat HDR.I Apart from the obvious response is there any reason why this arrangement would cause problems?
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Old 10-03-2011, 16:46
grahamlthompson
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On a French forum a contributor having problems with some freesat channels has revealed he has two dishes set to 28E one connected to LNB 1 and the other to LNB 2 inputs of his Freesat HDR.I Apart from the obvious response is there any reason why this arrangement would cause problems?
No reason at all, in fact if you look at the manual P16 it shows two dishes. Bit of an odd arrangement would seem a better idea to use a quad lnb on one dish and use the second dish on say 19.2 E and diseqc switch it with one of the 28.2E inputs to give access to both orbital locations using non-freesat mode. The OP says it's the way his landlord gives him two feeds though.
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Old 11-03-2011, 17:41
beejay3
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No reason at all, in fact if you look at the manual P16 it shows two dishes. Bit of an odd arrangement would seem a better idea to use a quad lnb on one dish and use the second dish on say 19.2 E and diseqc switch it with one of the 28.2E inputs to give access to both orbital locations using non-freesat mode. The OP says it's the way his landlord gives him two feeds though.
Why do you mention 19E as there was no mention of anything other than freesat?
Are you following the French forum thread where the OP now states he has three dishes on two houses but has only referred to freesat and 28E and there has been no mention of a landlord?
Or is the poster running threads in more than one forum?
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Old 11-03-2011, 17:49
grahamlthompson
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Why do you mention 19E as there was no mention of anything other than freesat?
Are you following the French forum thread where the OP now states he has three dishes on two houses but has only referred to freesat and 28E and there has been no mention of a landlord?
Or is the poster running threads in more than one forum?

I responded to a post from someone who has two dishes as a result of his landlord. He was having problems with a foxsat-hdr in recording two channels at the same time. A factory reset sorted it out. The reference to 19 East was simply a suggestion, normally it would be pointless having two dishes to feed a single twin tuner pvr.
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Old 12-03-2011, 17:37
beejay3
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I responded to a post from someone who has two dishes as a result of his landlord. He was having problems with a foxsat-hdr in recording two channels at the same time. A factory reset sorted it out. The reference to 19 East was simply a suggestion, normally it would be pointless having two dishes to feed a single twin tuner pvr.
Just a coincidence then. Same problem but my poster has no landlord and has three dishes.....and lives in France!
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Old 13-03-2011, 10:28
SWIZZ?
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Just a coincidence then. Same problem but my poster has no landlord and has three dishes.....and lives in France!
Your poster needs to be aware that by connecting to 3 dishes his HDR might be exposed to 3 electrical phases & therefore 400volts, if in fault conditions.
LNBs are probably designed for connection to only one phase.
Mind you I'm not an expert in electrics, but I expect someone who is could direct you to an appropriate thread.
David
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Old 13-03-2011, 10:37
Jepson
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Your poster needs to be aware that by connecting to 3 dishes his HDR might be exposed to 3 electrical phases & therefore 400volts, if in fault conditions.
LNBs are probably designed for connection to only one phase.
Mind you I'm not an expert in electrics, but I expect someone who is could direct you to an appropriate thread.
David
The power supplied to an LNB is DC and should be referenced to the ground or neutral which is independent on phase. (Similarly any signal paths, although AC, should be referenced to ground or neutral.)

I expect Graham can give you chapter and verse as that was his field.
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Old 13-03-2011, 11:06
davemurgatroyd
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Your poster needs to be aware that by connecting to 3 dishes his HDR might be exposed to 3 electrical phases & therefore 400volts, if in fault conditions.
LNBs are probably designed for connection to only one phase.
Mind you I'm not an expert in electrics, but I expect someone who is could direct you to an appropriate thread.
David
That can only be a problem if the dishes are connected to different properties or different flats within a communal installation where the properties themselves are connected to different phases of the mains power supply where the local mains supply is multiphase. It does not usually occur in a single property unless it is very large or occasionally multi-occupancy. The problem does not arise if the dish and cabling are suitably "earth bonded"
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Old 13-03-2011, 11:12
davemurgatroyd
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The power supplied to an LNB is DC and should be referenced to the ground or neutral which is independent on phase. (Similarly any signal paths, although AC, should be referenced to ground or neutral.)

I expect Graham can give you chapter and verse as that was his field.
Not true with a lot of equipment having switch-mode power supplies or being double insulated there is very little AV equipment that may have any connection to earth. Often connections to earth on such equipment used to cause "earth loop" problems which could only be simply cured by removing all but one of such connections to earth. There is a vast difference between "signal earth" and mains earth and the two are usually not connected unless "earth bonding" is applied to aerials, dishes and cabling.
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Old 13-03-2011, 13:38
grahamlthompson
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The power supplied to an LNB is DC and should be referenced to the ground or neutral which is independent on phase. (Similarly any signal paths, although AC, should be referenced to ground or neutral.)

I expect Graham can give you chapter and verse as that was his field.
As Dave says there is normally no earth reference unless one is provided. It matters little if the DC is provided by a switch mode power supply or an isolating transformer with a bridge rectifier, if neither end of the secondary wiring is earthed bonded or either of the DC outputs of a switch mode power supply the DC output floats in respect of earth. Earthing either of the positive or negative terminal will simply provide a reference, no current will flow.

The 220V output of a bathroom shaver point is an example, it's fed by a 1:1 isolation transformer. Just like the above a fault to earth will not create any current, merely tie one end of the secondary wiring to earth potential.

The dc excitation in a large alternator is similary floating. A earth fault on one of the connections is detected but the alternator can continue to run until a convenient time is found to repair the fault.

As to the two dish question as said it depends on the source of power for the two dishes. Larger properties converted into smaller rentable divisions generally only have a single phase supply in the UK. In France though domestic multiphase installations are quite common.
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