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Archive (2002-)
All posts by Michael Perry
Below are all of Michael Perry's postings, with the most recent are at the bottom of the page.Whilst broadly agreeing with Michael Walker, he doesn't mention one key factor against internet deliver - server capacity. Those of us with the benefit of fast broadband, my new service is running at about 36 Mbps, a number of services run quite slowly and appear no better than my old service which ran at 1.9 Mbps. The problem is that whist the data that gets onto the internet transfers quite quickly, many servers are just not able to deliver the required data fast enough for all those asking for it. So the main 'bottle necks' are at the servers and not entirely the fault of internet connections. Having a fast connection does not make the provision of the data by the server any faster. Indeed, it may be slower because of the workload placed upon the server itself.
Now consider what happens when some thousands of people decide they want to watch a programme via the internet. The server tries to deliver the data sequentially to each individual viewer, but because there are so many each individual stream takes up the bandwidth available at that server and puts a load onto the NICs and processors. If there is any limitation (which there always has to be) in that delivery then the viewer may well suffer buffering. Then consider that an HD stream has more than twice the data of an SD stream, so more workload for the server. Then consider UHD or 4k - with at least 8 times the data requirement as SD and so the server workload has grown enormously! Then add another million viewers!!!
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Ron
By 'TV reception' do you mean Freeview? Or do you mean FreeSat? Or do you mean Sky TV? They are all different and should not be confused with each other.
Reception of the terrestrial services provided by FreeView requires a suitable aerial correctly mounted on the house and aimed at a ground-based transmitter (there are many and a Post Code would help us advise which may be the best for your location). So you cannot use a dish to receive those services. Obviously you need a suitably equipped TV set or a 'set top box' designed for Freeview reception.
Reception of FreeSat and/or Sky TV is only possible by using a dish suitably aimed at the required satellites and feeding the signals into a suitable receiver, designed either for FreeSat or Sky reception. Note that Sky normally requires a subscription if you want more than just the basic PSB services. Any TV set will be able to display the programmes received this way, but some modern TVs have an in-built tuner for the satellite signals, some being capable of HD as well as SD services. Sky reception is always by using a 'set top box' which they supply when you take out a subscription with them. Note also that an aerial will not enable reception of satellite provided services.
Hope that helps?
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Mike Parker
Presuming you were using a satellite dish and receiver, the loss i=of BBC etc is because there was a change made to the beams used for those services such that they are no longer receivable in many parts of southern Europe. The only way you might get some of them is either via a local re-broadcaster (but I'm not in Spain so not aware of any) or via some internet-based provision.
The service mentioned by John Wilkins may be worth investigating. Their webste is at
IPTV Spain |Broadcast English TV Costa del Sol M?laga Marbella - hope that is useful.
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Rob:
Thought is has yet to be officially confirmed, I understand that the 700-800 MHz range is set to be 'sold off' so the spectrum could, perhaps, be used for 4G or 5G mobile usage.
Transmitters, like Oxford, that currently broadcast at least some of their signals will be adjusted so that they transmit at lower frequencies. That is why we have oftem suggested people have either a Group K aerial, which covers all of the Group A channels as well as most of those in Group B so will be capable of receiving all the channels after the adjustments, or else have a log-periodic aerial which covers the UHF TV spectrum so is suitable for the current frequencies as well as all those envisaged in the foreseeable future - subject to Ofcom's confirmation of course.
That is likely to be the situation for next 5-10 years but after that there could be more major changes but that is open to speculation at present with no firm 'hints' coming from Ofcom.
So, do not worry about loosing your Oxford signals for a while yet.
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hade:
You have not given a post code so we cannot determine which is you local transmitter. That means we cannot check whether there are any problems reported or whether there are problems between you and that transmitter. As you have posted on the page relevant to Heathfield transmitter, a post code would allow us to confirm, or otherwise, whether that is the best for you particular location.
There is no such thing as a 'digital' aerial, all UHF aerials can receive both digital and analogue signals perfectly well as long as it is of the correct group and aimed at your recommended transmitter.
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Gareth:
There is no indication that the Mendip transmitter has any problems nor scheduled work being done.
I also use Mendip and in Trowbridge there are no problems being experienced either by me or my neighbours.
It's probably worth checking that all your connections are good.
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Anthony:
I have been in the professional electronics business since 1960 (but am now retired) and we always had a saying comparing analogue and digital systems. It states that analogue is nearly always right but digital is nearly always wrong. It's based on the fact that analogue signals 'follow' the electricalwave patterns except when interference spikes creep in and that digital signals are based on 'occasional' samples that are used to produce a binary numerical representation of the signal leval *at the moment of sampling*. As there is a gap between sample points, there is inevitably some parts of the original signal missing. Top try to overcome that a mathematical technique called interpolation is used to try and 'best guess' what happened between the actual samples. There is no way of knowing just how accurate those 'guesses' are, the mathematical calculations can be very wrong, a bit wrong, a bit right or almost right - the only part of a digital signal thjat is ever 'right' is that representing the actual sample point.
Then add into the equation that fact that DAB techniques are not of the best, DAB2 is better and there are other more recent developments that show improvements.
Then consider the problems of DAB reception in cars. Some expensive models have a reasonable equipment level that can work - but still has signal loss problems in my experience. Analogue FM radio on the VHF waveband is much better, not perfect admittedly, and works fairly well in moving cars even when the signal levels are poor (DAB drops out often under those conditions).
I'm afraid it is again a situation akin to that with terrestrial TV broadcasting. We had a fairly good analogue service that was stable. There were ways to improve it (I worked on the Eureka 95 project to give 1250 line TV, not just 1080), it already had fairly good stereo using Nicam and we had a teletext service in Ceefax and ITV's Teletext (formerly known as Oracle) that had pages and pages of information available when you wanted. That was replaced with a digital system because it allowed more money to be gained from broadcasters, at the expense of viewers' comfort and enjoyment. Just listen to all the complaints about even more repeats and shows that some consider 'rubbish'.
Have things been improved by going digital? My opinion is that it has not and has made viewing more difficult for viewers. Non-technical people don't know why they have to keep retuning and they get nothing for doing so. I suspect similar may be the case with 'all digital' radio services. And it may be a subtle ploy so that all TV and radio can be put on the internet (that not everyone can get according to the Government) so allowing Ofcom to sell more spectrum at high prices to toy phone, sorry - mobile phone, companies so they can make even more profit and put more people at risk of bullying and trolling.
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John Martin
So what I surmise about the internet not being capable of delivering IP TV in a way that is reliable for all viewers, as was the case with analogue TV, is born out by your submission for which I am grateful.
But it is Ofcom who take the decisions as to how and when the possible changes might happen and they don't seem to be particularly familiar with the technical issues. The do appear to be familiar with the profit motive though.
Add in also the fact the the Government have stated that currently they think some 850,000 people will not be able to get an internet connection by terrestrial means so are considering offering a 'sweetener' to encourage them to look at satellite internet services. These may help some but with surprisingly high latency makimg the playing of on-line games almost impossible (if that's what they want to do) and there are still some locations that, because of mountains and so on, cannot get satellite signals from the Astra satellites at their 28.5 and 28.5 degrees East orbital positions (you have to have uninterrupted line-of-sight between your dish and the satellite) so they can't benefit from satellite internet nor TV.
Reflecting on the changes over recent years (at least the last 10) and the possible future changes, I am still very concerned that the interests of viewers is being ill-served.
Thanks again for your useful submission.
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Briantist
I thionk we need to separate out the data for those listening via DAB specifically and those listening via the internet. Both as digital delivery media but should not be 'lumped' together as they are different and appeal to different users.
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Thursday 5 February 2015 10:14PM
geoffrey o'neill:
From my personal view, I will happily stay with FM but not DAB. As a very experianced choral singer since the age of 11 I have come to expect good quality reproduction but DAB does not give anything like the same sound or tonal quality experience as a vinyl record. DAB is definitely worse than a CD to my ear.
But I agree thjat Long and Medium wave transmissions have a limited future, despite the fact that they have the best reception penetration because of the lower frequencies used for the carrier.