Omega Owners Forum
Omega Help Area => Omega Electrical and Audio Help => Topic started by: TheBoy on 22 September 2008, 13:43:09
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I was out with my eldest brother the other day in his heap of poo X5, and it dawned on me...
...when the analogue TV gets turned off, will in car TVs die a death (obviously the analogue ones will) - will they make digital ones, ie is it possible to make a good enough aerial for in car TVs?
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Oh, and no, I haven't turned into a chav - I have no desire for a TV in my car. It was a purely tech question...
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says the man fitting a CID, which could be modified to have a VGA signal ::)
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iic the ariels could be to blame too? As some old TV ariels don't have the capacticy to pickup digital signals?
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says the man fitting a CID, which could be modified to have a VGA signal ::)
Thats irrelevent. I am not having a TV in my car...
...FFS, the one in the house is troublesome enough ;D
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iic the ariels could be to blame too? As some old TV ariels don't have the capacticy to pickup digital signals?
All car aerials will be wideband anyway (all thats required for digital), the question I was posing was could a car aerial be powerful enough and selective enough?
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iic the ariels could be to blame too? As some old TV ariels don't have the capacticy to pickup digital signals?
All car aerials will be wideband anyway (all thats required for digital), the question I was posing was could a car aerial be powerful enough and selective enough?
Seeing the signal qauilty of TV's in BMW 7 series, chances are low :-/
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When they turn the TXs up it will be fine, or use mobile DTV.
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Oh and put a DAT75 on the roof ;D ;D ;D ;D
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Digital TV receivers for in car use have been on sale for a good few years now - (keep up !! ::) )
Mixed feelings about them personally as the reception seems to be poorer than the analogue when going along. At least when the analogue signal dropped out the picture went fuzzy but was still tolerable, the digital one just goes blank or covers the screen in squares. Most annoying.
If you intend to put something in a car, don`t bother with a TV tuner at all, stick with DVD and if you want something for a caravan, or RV its cheaper these days to use a mobile sattellite receiver and dish, as they are now available for around the £100 mark.
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If you intend to put something in a car, don`t bother with a TV tuner at all, stick with DVD and if you want something for a caravan, or RV its cheaper these days to use a mobile sattellite receiver and dish, as they are now available for around the £100 mark.
Never had a problem with Freeview - I use a PVR as well
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Never thought of putting a freeview receiver in a car !!
I`ll have to try that out on the next customer !!
I wonder if the signal would be strong enough to use it?
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Never thought of putting a freeview receiver in a car !!
I`ll have to try that out on the next customer !!
I wonder if the signal would be strong enough to use it?
I think at the moment it could be difficult to get a decent signal. It's marginal from a rooftop antenna with 15db gain or more in places, after all. Might improve as stated when the analogue carriers are removed from the equation and the transmitters can be driven harder on the digital carriers.
The other factor to consider is multipath. DTV was designed for static viewing. Using it in a car introdues a lot more multipath which will really screw up the bit error rate if, as I suspect, the equalisation in the receiver isn't up to coping with it.
That means watching it on the move would be a problem (why would you?) but also watching it when parked up in a city full of tall buildings or by a road with moving traffic. That's not going to be resolved by stronger signals. It's something the modulation and channel coding of the signal wasn't designed to cope with.
Kevin
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That means watching it on the move would be a problem (why would you?)
Why would you? I think something to do with keeping the little cherubs on the back seat quiet rather than the old fasioned method of communicating with them, playing I-Spy, or even the excellent method of keeping kids quiet in my day - thumping them very hard.
I take your point about the signals though - :y
Amazing really, we tell the parents the signal will be crap, but still they won`t listen and keep paying us extortionate money to fit them, and then moan about it afterwards.
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Why would you? I think something to do with keeping the little cherubs on the back seat quiet rather than the old fasioned method of communicating with them, playing I-Spy, or even the excellent method of keeping kids quiet in my day - thumping them very hard.
OK. Point taken. :-[
Guess who hasn't got any "little cherubs"? ;)
It's the problem we face with all these digital standards. As they are optimised to a greater extent, their range of application narrows to the point where you need a new standard for every application.
Maybe DVB-H or MediaFLO will eventually provide the answer. I must admit, I never appreciated the point of TV on a mobile phone, but to the back seat of a car on a long journey maybe it has its merits.
Kevin
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I guess many of the advances to make mobile DVB happen will be in the receivers, making them more powerful and more selective at the electronic level, given that other factors are reasonably static (if the fat idiot in No 10 sells off the bandwidth when analogue goes, will there be much scope for boosting transmitter power?)
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I guess many of the advances to make mobile DVB happen will be in the receivers, making them more powerful and more selective at the electronic level, given that other factors are reasonably static (if the fat thingy in No 10 sells off the bandwidth when analogue goes, will there be much scope for boosting transmitter power?)
The problem is, DVB-T was designed for a large number of channels at a relatively high bit rate (so the picture doesn't look offensive on a ruddy great TV) but with the data not coded very robustly due to the relatively static nature of most receiving stations and the ability to put up high gain antennae.
The demands of a mobile setup are for a low bit rate (screen is going to be small - so no point in high quality), more robustly coded signal so better error correction and equalisation can be applied by the receiver and it can cope with the multipath you can get on the move.
Whereas with FM radio later innovations like RDS allowed it to be useable in a mobile environment the requirements are so conflicting with DVB-T it seems less likely. However, when FM Stereo was first launched you'd probably have been branded a madman for suggesting listening to stereo radio broadcasts in a car. Where would you put all the valves, for a start? ;D So who knows?
There are also technologies like HSDPA and LTE which, if they got cheap enough, might allow mobile streaming of video over IP to mobile users.
Kevin
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I guess many of the advances to make mobile DVB happen will be in the receivers, making them more powerful and more selective at the electronic level, given that other factors are reasonably static (if the fat thingy in No 10 sells off the bandwidth when analogue goes, will there be much scope for boosting transmitter power?)
The problem is, DVB-T was designed for a large number of channels at a relatively high bit rate (so the picture doesn't look offensive on a ruddy great TV) but with the data not coded very robustly due to the relatively static nature of most receiving stations and the ability to put up high gain antennae.
The demands of a mobile setup are for a low bit rate (screen is going to be small - so no point in high quality), more robustly coded signal so better error correction and equalisation can be applied by the receiver and it can cope with the multipath you can get on the move.
Whereas with FM radio later innovations like RDS allowed it to be useable in a mobile environment the requirements are so conflicting with DVB-T it seems less likely. However, when FM Stereo was first launched you'd probably have been branded a madman for suggesting listening to stereo radio broadcasts in a car. Where would you put all the valves, for a start? ;D So who knows?
There are also technologies like HSDPA and LTE which, if they got cheap enough, might allow mobile streaming of video over IP to mobile users.
Kevin
I remember how long it took for RDS to catch on, and how expensive it was in its day. There is no doubt that it will happen, and will probably happen faster nowadays with many technological breakthroughs that are now possible and there is a definate demand for it -
what worries me though is not the technology, but its the Format wars that will undoubtedly break out over different manufacturers which could prove costly for those wanting to purchase equipment now - we all remember the VHS and Betamax wars, well it happened again recently didn`t it between HDDVD and Blueray ? -
:'(
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Mobile streaming is the only existing practical method for digital broadcasts to the car.
Trouble is that the current digital setup is based around as lower power transmitted signal as possible and there is not much scope for improving the receivers much beyond what they achieve today.
I cant see them ever winding the power up following the analogue switch off.
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am i right in thinking the mobile(phone) tv band width wont be available until 2010? when the band width re shuffle is finished. Dont see any point worrying about it until thats available, presuming the car makers will make use of it?
Nokia(yes, gay, i know) have a hand set or 2 with it featured for other markets, i might be able to afford ,and have the kids to justify, the cid conversion by then.
I dont suppose a better/cheaper way has come to light to convert the cid to work with a nokia tv out?
Oof on the cid, maybe one day.