Jump to content

Digital Rollout: Bunbury & Kalgoorlie Next To Launch!


Recommended Posts

James Kirk,

None of what you said applies, because the analog channel is the next channel higher so the sound carriers are further from the digital signal.

If what you say about receivers is true, then in Brisbane for example what happens to the reception of digital channel 6 and analog channel 7 which is the same way around. Similarly channels 8 and 9. I don't hear anybody screaming since 2001. This is why the digital power is a quarter of the analog vision power.

AlanH

Link to comment
Share on other sites



  • Replies 272
  • Created
  • Last Reply

Top Posters In This Topic

James Kirk,

None of what you said applies, because the analog channel is the next channel higher so the sound carriers are further from the digital signal.

If what you say about receivers is true, then in Brisbane for example what happens to the reception of digital channel 6 and analog channel 7 which is the same way around. Similarly channels 8 and 9. I don't hear anybody screaming since 2001. This is why the digital power is a quarter of the analog vision power.

AlanH

*

Oh dear, he still hasn't grasped that adjacent analogue services were being referred to, not an adjacent analogue and digital service.

Why is digital 'power' a quarter of 'analogue' power? One might be fooled into thinking that this hasn't be done, then redone and then done again just for good measure, but I'm sure those with a wee bit of skill will be able to use the forum search and discover.... that it has. Consider that (geez, I guess this makes it yet again!) analogue 'power' levels vary considerably with the picture content, have a minimum level to prevent too much noise being visible.... no wait, its been done enough times already for even alanh to grasp it and I know he has because he 'participated' in the 'discussion' at the time. :lol:

Here's a question: Is anyone here but alanh expecting a large increase in digital TX power (in general, there are a few specific cases where there will be an increase) once analogue is switched off there by removing the necessity to operate digital at "one quarter"? Anyone apart from alanh that is. ^_^

*quoted incase the post mysteriously changes...;)

Edited by DrP
Link to comment
Share on other sites

Here's a question: Is anyone here but alanh expecting a large increase in digital TX power (in general, there are a few specific cases where there will be an increase) once analogue is switched off there by removing the necessity to operate digital at "one quarter"? Anyone apart from alanh that is. ^_^

The majority of digital transmitters are running at full power and have been for a very long time, so no, there will be no increase in power of most digital TX after analogue switchoff.

Link to comment
Share on other sites

You know it, I know it, all the informed people on this forum know it. The typical 1/4 of analogue peak is determined by reasons other than adjacent analogue service inteferrence.... those reasons just seems to have escaped alanh for the time being. ^_^

Link to comment
Share on other sites



Guest stump_1100
The majority of digital transmitters are running at full power and have been for a very long time, so no, there will be no increase in power of most digital TX after analogue switchoff.

Actually they aren't but it really has little to do with adjacent channels. Let me say up front that there are some sites (and I only speak for WIN and Prime transmission sites) that are running at 6dB down due to an adjacent analogue channel, these will increase in power (but not max) when ASO occurs in that region.

Having said that, the DTV transmitters are generally specified to have at a least one more PA than required (for example if 5KW is required then we might use a 7.5KW, depending on cost etc). This allows us to have some spare capacity and not run the transmitter "flat out" thus getting better efficiency in transmit MER. Obviously there are other benefits such as less heat stress and some redundancy in components.

Edited by stump_1100
Link to comment
Share on other sites

I think MTV meant that they are running at the power level that is the desired permanent level not that the TX's are at the limit of their ability when he says 'full power'. Some TXes are being run lower than desired to avoid adjacent channel inteferrence and probably co-channel too, there's no disputing that.

However, if one swallowed alanh's post hook, line and sinker one could be forgiven for thinking that all TXes are running at a lower then desirable level, which of course simply isn't the case.

Link to comment
Share on other sites

Since all regional analog transmitters have been switched off in SA, Victoria and Broken Hill, which ones have now had their radiated power increased?

All receiver installations have been made using the power radiated when analog transmissions were on air. So why increase the radiated power?

It's a good idea to use a more powerfull transmitter than is required and then reduce the drive to the output stage to keep the power within the licence.

AlanH

Link to comment
Share on other sites

I think MTV meant that they are running at the power level that is the desired permanent level not that the TX's are at the limit of their ability when he says 'full power'.

Yes, that's exactly what I meant.

Link to comment
Share on other sites

Since all regional analog transmitters have been switched off in SA, Victoria and Broken Hill, which ones have now had their radiated power increased?

All receiver installations have been made using the power radiated when analog transmissions were on air. So why increase the radiated power?

It's a good idea to use a more powerfull transmitter than is required and then reduce the drive to the output stage to keep the power within the licence.

AlanH

Because alanh, you stated that all transmissions were at 1/4 analogue peak in order to reduce adjacent channel inteferrence so a logical conclusion, drawn from your illogical post, is that when analogue is switched off all digital services will demonstrate a considerable increase in transmission power. Of course, this did not happen leading to the only possible conclusion of "once again alanh was talking out his arse".

BTW, you can't edit the post to worm your way out of this one. ^_^

Further, all installations aren't new yet the signal level pulled in by an existing installation is apparently inexplicably within the nominal range - ie, real world experience does not reveal low signal levels for most installations - old or new. Has the reason for '1/4' peak managed to sink in yet? Perhaps you can state the actual reason, if its not too embarrassing for you that is. ^_^

BTW, I recall someone making frequent posts about reduced carbon emissions comparing a digital transmission to an analogue transmission a while back. This person unfortunately demonstrated a degree of misunderstanding regarding the average power level of analogue transmissions compared to the average level of digital tranmissions too. That must have been a bit embarrassing for that person too. ^_^

Edited by DrP
Link to comment
Share on other sites



  • 2 weeks later...

So, only a few days to go until switch-on of the new digital channels...

Is everything ready to go for the 27th, or are we to expect further delays? I'll be rather peeved if it's the latter (tho I have foxtel - who dosn't? - so plenty to keep myself busy)..

Link to comment
Share on other sites

So, only a few days to go until switch-on of the new digital channels...

Is everything ready to go for the 27th, or are we to expect further delays? I'll be rather peeved if it's the latter (tho I have foxtel - who dosn't? - so plenty to keep myself busy)..

It's the 28th and yes, all is going to plan. Once the remaining digital channels are added to VAST tonight, the site will no doubt have to test it all out and tweak things over the next 2 days, then they'll switch it on. They're moving WIN analog to ch40 at the same time, so Bunbury viewers won't Wake Up With Today™ until they suss it out and re-tune their (hopefully digital) TV's. :P

Link to comment
Share on other sites



It's the 28th and yes, all is going to plan. Once the remaining digital channels are added to VAST tonight, the site will no doubt have to test it all out and tweak things over the next 2 days, then they'll switch it on. They're moving WIN analog to ch40 at the same time, so Bunbury viewers won't Wake Up With Today™ until they suss it out and re-tune their (hopefully digital) TV's. :P

No.... It's more likely there'll be a whole lot of confused old farts clogging up WIN switchboard wondering why they can't get WIN on their 20-year old television sets anymore....

A lot of people haven't converted to digital yer, and these same people wouldn't know how to use their tvs beyond switching channels....

Link to comment
Share on other sites

Anyone got any idea on when the rest of the state is going to catch up?

All of WA will be fully digital by mid 2012.

The rest of the South West is next, to be fully done by Dec 31, which means sites will be switched on between now and then. I just got word today that Kalgoorlie will be switched on by Sept 30, not Jul 28, so there's already some delays. IIRC, the South West takes priority due to an expiring DVN link.

Link to comment
Share on other sites

It's the 28th and yes, all is going to plan. Once the remaining digital channels are added to VAST tonight, the site will no doubt have to test it all out and tweak things over the next 2 days, then they'll switch it on. They're moving WIN analog to ch40 at the same time, so Bunbury viewers won't Wake Up With Today™ until they suss it out and re-tune their (hopefully digital) TV's. :P

Even WIN agree with this... They started running infomercials on Sun 24th July informing viewers of the changes - re-tune analogue from ch 39 to ch 40, and do a full scan on digital to pick up all new channels...

Link to comment
Share on other sites



Even WIN agree with this... They started running infomercials on Sun 24th July informing viewers of the changes - re-tune analogue from ch 39 to ch 40, and do a full scan on digital to pick up all new channels...

I saw this and recorded it just then!

Link to comment
Share on other sites



  • Recently Browsing   0 members

    • No registered users viewing this page.




×
×
  • Create New...
To Top