Bugsy Posted December 13, 2007 Share Posted December 13, 2007 Martin, as you are clearly knowledgeable on this subject can you tell me exactly what difference there is between an oval dish and a round one. I have an 80mm oval and apart from having to position it sightly more vertical than a round one I can see no difference in sound or picture quality. I would also appreciate some info on downloads for my Technomate box. I bought it and its an excellent piece of kit but have yet to venture into the misty world of downloads.ThanksGary. Link to comment Share on other sites More sharing options...
Martin963 Posted December 13, 2007 Share Posted December 13, 2007 Under normal circumstances there shouldn't be any difference in quality; the only aspect in which an oval dish scores is its ability to discriminate against unwanted signals on an adjacent satellite. To be honest I have no idea why Sly thought this might be useful, at least not over the lifetime of the current generation of installations. And on a 43 cms dish the advantage is minimal.As to Technomates, well you could have a look at the alsat or satpimps sites (google will find them). Link to comment Share on other sites More sharing options...
Bugsy Posted December 13, 2007 Share Posted December 13, 2007 Thank you. Link to comment Share on other sites More sharing options...
Fridgeman Posted December 13, 2007 Share Posted December 13, 2007 Bugbear I have sent you a PM Link to comment Share on other sites More sharing options...
Bugsy Posted December 13, 2007 Share Posted December 13, 2007 Got it, Thanks, Link to comment Share on other sites More sharing options...
Gyn_Paul Posted December 13, 2007 Share Posted December 13, 2007 The theory - as I understand it - goes like this...A round dish has the lnb in the centre, the parallel signal beam arrives 'head-on' to the dish and is equally (as in top, bottom, side, side) focused onto the lnb in the centre. However to position the lnb in this place there must be some sort of metalwork support (usually a triangle) which is casting a shadow on the dish surface, thus attenuating some portion of the signal.With an oval, or offset, the signal arrives (as it were) from a direction above the centre axis of the dish. The point of focus is below the beam of the signal, and the LNB's supporting arm even lower, therefore there is nothing obstructing the signal, and no attenuation. This was important in the early days when the gain from the lnb was far less than the modern ones, so every scrap of potential signal was worth getting. These days, as Martin intimated, it makes hardly any difference, except that the narrower the dish, the easier it is to find the damn satellite in the first place !There. Sorry you asked, aren't you?p Link to comment Share on other sites More sharing options...
Martin963 Posted December 13, 2007 Share Posted December 13, 2007 That's probably what the question was about. I took it to mean the difference between a sly-style dish and conventional offset. But I think you're right, the question was probably referring to a cassegraine (or do I mean gregorian) style dish. Link to comment Share on other sites More sharing options...
Bugsy Posted December 13, 2007 Share Posted December 13, 2007 [quote user="Martinwatkins"]That's probably what the question was about. I took it to mean the difference between a sly-style dish and conventional offset. But I think you're right, the question was probably referring to a cassegraine (or do I mean gregorian) style dish.[/quote]Not a sly dish, Martin, but an 80mm solid oval I bought in spain six years ago. Link to comment Share on other sites More sharing options...
Martin963 Posted December 13, 2007 Share Posted December 13, 2007 Ah, my mistake. Sorry. But I bet it looks jolly technical though! Link to comment Share on other sites More sharing options...
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