Aircooled VW South Africa

Chris wrote:It actually does work like that

It is measured by db-millivolts per meter.So the higher the output,the more viewers.

It is the same way power in your house gets used.The more appliances gets switched on,the more powere is used.

Chris, I am not saying it is not how it works..... It just dont makes sense to me, that's all. Now, on the other hand, your electricity example makes sense. However, I cant 'link' that with the signal explanation. The more appliances that run, the greater the 'draw' on the system. However, this to me is like instant 'on the demand'. Where as once a TV signal is broadcasted, it is 'out there'. Now coming back to my previous example.... SABC 3 for example can say in advance, for a one off program, how many people are going to watch it. So they 'project' 2000 possible viewers, so they broadcast for example 10 000 db-millivolts per meter to 'cover' the 2000 viewers, so they send out the signal.... Now let's say there is nothing on TV that interests another 1500 viewers, and they switch over to SABC 3, there wont be enough signal to cover them!? What I cant understand, is how do they effectively 'measure' how much braodcasted(ie 'already out there') signal is being 'absorbed, to effectively adapt for either more or less signal strenght...??? Now, with Cable/sky top boxes that are either connected direct with cable or telephone lines(like our Sky box SHOULD be ), there can be some kind of feedback of who is on a certain chanel at any given time...., then yes, sure I get it..... But already broadcasted signals I just dont get.

It is like me putting enough water in a kettle for 4 people that wants coffee. Now suddenly me neighbour joins the party and I dont have enough hot water for his cup......

Watched the program quick. Nice insert - GO VUYO! , but so short?
Would have loved a bit more video material on the meet, but it looks like it was great

missed it and i dont hav a betamax

I'm not the guru here wrt signal strenght and the like.That is the explenation I got and apparantly that's how it's done.The broadcasters has meters measuring the outgoing signal strength and according to that they can determine how many viewers are drawing signal.

Btw Samba,nice Bus.Why must we wait till it's on TV before we see what it looks like?

Where are the pics man!?

Iaaaa dunno... Electricity wise, yes, that's easy, any generating power station can only supply as much as is demanded, (this is an important concept!) because we're hard wired into the grid. But a TV station can send out loads of power (signal power) in fact, they send out a certain rated signal strength for which they are licenced (their licence covers not only the frequency band but also signal strength), what gets picked up gets picked up, the rest dissipates (by the inverse square law, if anyone asks...) and is lost. There is no way the station can know how many amps are being drawn and so have a "live" read out on a little gauge somewhere to tell them who's watching what.

It is a marketing survey that determines viewer numbers, but THAT is a different story altogether. I know nothing about marketing surveys... Although I recently learnt what a "high commitment product" is, versus a "low commitment product", whoopee! All my live I've been dying to know that...

They measure it by the signal strength that is send out.If only a 1000 viewers watch a specific channel,the signal sent is not so high.The more viewers,the stronger the signal has to be.That is measured in inclinations of 1000.

Come now Chris... this cant be... Made me laugh though
What if there are lots of people close by ... is that the same as a few people far away?

More like this - http://en.wikipedia.org/wiki/Nielsen_Ratings
read it and you can see why its not an exact science.

Good day ACVW's, I missed the show as well, but interesting comments concerning the ratings of a show. As far as I know it is done by some form of market research and the history of viewing patterns and preferences.

I am a broadcasting engineer, The Ron & Gill answer about the TV signal is correct. To try and explain it simply, SABC TV transmitters generate say 10kW (10 thousand watts) of radio frequency power. The signal is radiated into space by an antenna that shapes the pattern so that most of the signal is radiated at a low angle towards the horizon, in a circle around the transmitter, aiming at where the viewers live. By modifying the radaition pattern the effective radiated power is increased, typically by a factor of 10 to 30 times, so we end up with an effective radiated power of say 100kW (100 thousand watts). (Think of a balloon being squashed on a table, it gets flatter and the diameter increases). The power is fixed, the transmitter typically has an automatic level control (ALC) loop that keeps the output constant.

The antenna at the viewers end also shapes the pattern to increase the received signal (this is commonly known as the "Gain" of the antenna). A typical signal would be say 1mV (one millivolt or one thousandths of a volt) The antenna impedance is 75 ohms. Calculating the effective power gives an answer of 13nW (13 to the power of -9 Watts). This is very small. Lets now say there are one million viewers with their eyes glued to the set hoping to catch a glimpse of Ferdi's meet. Then 13nW x 1,000,000 viewers consume a total of 0.013W or just more than 1/100 of a Watt. And 100,000 Watts is radiated. So even with a million viewers, a neglegible fraction of the available power is actually used, the rest is radiated into space, unutilised. Digital and satellite TV are much the same. The advantage of digital is the more efficient use of bandwidth, one can now fit up to 8 digital channels into the space occupied by one analogue channel. Hope this helps.

That's why I said,I'm not an expert,that is just what I got.The Nielsen is in anyway not accurate as well.In the US there is only a little number alocated to a few homes.They then take how many of the viewers,using the Nielsen,are watching a specific channel.If 20% of them are watching a specific channel,they take it that 20% of the nation is watching that channel.

In the US recently,a TV stationWRGB, had to up the signal strenght of it's transmitter because people were complaining that their signal was poor.The station then increased the signal strenght by almost double to ensure that the viewers could recieve the broadcast.This was due to the amount of viewers recieving the signal.The increase in viewers demanded I higher signal strength.

But this is not the topic under discussion here.It is about Ferdi's and how many people watched it on Sunday,and unless you had poor signal,you must have been able to see it in TV.

OK,got some clarity on this matter.

They CAN determine viewers based on signal strength,but only on a digital system.Analogue can't be "read".The topics I read was all about digital and not analogue.It has to be a system that is intelegent where a signal is recieved like on a decoder.They can determine exactly how many viewers is watching a specific channel.

This is one of the reasons why SABC want to go digital.The other is money.The advertisers are demanding more accurate figures in terms of viewers and in certain cases,advertisers had to be refunded due to the fact that the projected sales wasn't reached after their product had been aired.

Most of the channels that give a viewer count,get the figures from the amount of people watching digital TV.That is why they can give accurate counts.SABC can only at this stage get a small percentage of their viewership via DSTV as they can see how many people are viewing a SABC channel via satelite.

The other way they determine viewer number is through cable networks like the ones in Europe and the US.I don't know how many people in those countries use cable TV,but it sounds like the Nielsen system is out dated and soon will be a thing of the past as the world moves toward digital.

So maybe DSTV can tell us how many people watched Ferdis on Sunday.

That is what I had in mind..... Analogue is projected viewers, but 'hard wired' systems can give ACTUAL feedback. Like our first year on Sky TV(UK). We 'had to' have our phone line plugged in into the decoder. PArt of the first year's contract. This way they got feedback(however, we didnt pay for the phone calls made to Sky. OBVIOUSLY that was one of the cables that I ''just couldnt figure out how to hook up''

PS. What is a thread without a good old fashioned HIGH JACK???

i got the episode will post it as soon as i can

vuyo wrote:i got the episode will post it as soon as i can

Hallo Koos!

Thanks for the call this afternoon,it was nice chatting to you again.Tried recording it on to DVD today,but it won't work.

http://s140.photobucket.com/albums/r35/ ... ys2009.flv

Great clip, Vuyo - thanks! If you can give me a hard copy some time, I can add it to the Youtube channel of ACVWSA