215 replies to this topic

[lesftv]

CWulf, on Jan 5 2011, 10:56 AM, said:

The issue isn't about me explaining the details but YOU accepting you don't know everything!

Alan,
Surely all "Mother Transmitters" have long since been replace with Neccies or Thomsons. Perhaps some of the low-power "fill services" may have vacuum tubes. However, any broadcaster worth its salt would have updated manyfold since 1956.
Analog has a lolg wat to go to swich-off in some areas. Hunter Valley and Northern NSW are due to switch off analog in December 2012.
I suggest you take a sedative and take a good rest. Everything will still be the same when you wake up.
lesftv

[alanh]

LesfTV,
You obviously did not look at the transmitter output power from the link I gave you. It is a current model. This power will be increased by the antenna gain to give a Megawatt radiated power.

You will note it is only in the output stage, and other transmitters have no valves. Thales make the valves and they are also transmitter manufacturers. The reason why they are used is because it is not possible to get such high power levels at the uppern end of the UHF band efficiently. Whilst most transmitters increase the output power by combining the output of multiple modules. The it is much harder at near 1 GHz and the losses are greater.

It is low powered transmitters which are all using VFETS in place of valves.

If the broadcaster who wanted to run lower power output was in SA excluding Adelaide, then nine high powered transmittera are already switched off.  Next in line are some very high powered transmitters in regional Victoria which will be off by the middle of this year. There is an Australia outside Newcastle.

AlanH

[lesftv]

alanh, on Jan 7 2011, 12:45 AM, said:

LesfTV,
You obviously did not look at the transmitter output power from the link I gave you. It is a current model. This power will be increased by the antenna gain to give a Megawatt radiated power.

You will note it is only in the output stage, and other transmitters have no valves. Thales make the valves and they are also transmitter manufacturers. The reason why they are used is because it is not possible to get such high power levels at the uppern end of the UHF band efficiently. Whilst most transmitters increase the output power by combining the output of multiple modules. The it is much harder at near 1 GHz and the losses are greater.

It is low powered transmitters which are all using VFETS in place of valves.

If the broadcaster who wanted to run lower power output was in SA excluding Adelaide, then nine high powered transmittera are already switched off.  Next in line are some very high powered transmitters in regional Victoria which will be off by the middle of this year. There is an Australia outside Newcastle.

AlanH

It is iteresting Alan, that when you are pushed into a corner, you skew the detate to something of absolute irrelevance. You do it time and again. Loosen up kid
lesf

Edited by lesftv, 08 January 2011 - 03:49 PM.

[crownms123]

digitalhome, on Feb 14 2010, 04:09 PM, said:

I have done quite a few antenna jobs around there and always use phased arrays. But you WILL need a signal meter to measure the signal/placement etc as it can be a little tricky to get a quality signal in that area.

Even with a phased array installation, as others have said on this post, a signal measurement is paramount to many digital installations. I have also experienced cases like yours where a phased array was used to replace a Yagi due to the same problem, but the antenna positioning played a crucial role in the signal outcome. Measurements as small as one metre or less between one point of a roof to another can make a difference between choppy digital reception on one or more stations to perfect reception on all stations. In the case I am referring to, the problems were appearing on NBN digital (from houses in Kotara and Wallsend), so the problem stations vary and not just on Prime and SCTEN all depending on the geographical area you live.

Edited by crownms123, 03 March 2011 - 12:44 PM.

[neversaydie]

Ok fellas,
              I live in Belmont North and for the last couple of weeks have been experiencing signal drop-out with ABC & NBN at night, any thoughts as to what is causing the problem.

Edited by neversaydie, 03 March 2011 - 08:54 PM.

[jaytv]

Hi All,

Hopefully I'm posting this in the right section ???

Current Set Up is as follows...
We have 3 outlets in the house... coming from a antenna to Masterhead amp into a spliter (with power pass) and then to the outlets. Outlet(A) is connected to the power source for the amp and then into a HD-STB... Outlet(' is connect to a PC with PCI tuner card and Outlet('C) is connected to a TV with build HD tuner... Runs lengths from the spliter are all pretty much the same.

Everything has been working perfectly until last week when,
Outlet(A) (HD-STB) started to pixelate on prime channels (7, 7mate, 7-2), this seemed to get worse at night ??? The same thing is now starting on the SC TEN channels also and occassionally NBN.
Outlet(' (PC - PCI Tuner Card)... no change, same as always.
Outlet('C) (TV with built in HD Tuner)... no change, perfect picture.

Would anyone have any suggestions what the problem may be ? I am thinking that the tuner in the HD-STB may be going, it's not very old, still under warranty. If I were to try it on another outlet (B or C) and have the same problem woud this point to the HD-STB tuner being the problem ? Can tuners start to fail like that and if so why ?

Thankyou in advance.

*** UPDATE ***
OK... I extended a cable from Outlet(A) to the TV at Outlet('C)... Result... Worked Fine. So, this ruled out the cabling and connections of Outlet(A).

I then tried the HD-STB on Outlet('C)... Result... Pixelation... therefore, I'm thinking the problem is with the HD-STB tuner. So I'm going to send this away to be looked at... I'll post back with the results.

Edited by jaytv, 09 March 2011 - 12:11 PM.

[jaytv]

***UPDATE***

Just thought I'd post this update...

1. Moved the amp power source from Outlet(A) to Outlet('C)
2. Replaced the power pass splitter. I replaced it with the same type just a new one.

At this time (it's only been 6 hours) all outlets seem to be working fine. Maybe the power source was causing some interference to the HD-STB on Outlet(A) ???

I'll give it a few days and see how it goes.

[ebonyblackdog]

Hi there -

As a new forum member I'm not allowed to post a new topic, but I just wanted some advice on the problem I'm having:

We live in Abermain (in between Cessnock and Kurri) in a 4 year old house. Antenna installed by builder - I have no idea what it is.

In 2007 we got all available digital channels perfectly, including the "Test channel" with the loop of Australian towns that one hd replaced.

Ever since ONE HD and 7Two started, we now have very unreliable reception for all channel 10 channels (5, 50, 55) and channel 7 (60, 61, 62, 63), it seemed to get worse the more channels that started. To the point it cannot be watched. 7 is slightly better than 10. It can be in any type of weather.

NBN, SBS and ABC channels are all perfect.

I managed to look at the signal strength reported by the tv and it was very low (less than 20% at times).

My questions are:
1. Does it sound like the problem is my aerial? And I should get someone to have a look at it?
2. Is it just problems inherent with these particular channels?
3. Is there something else I'm not thinking about??


Thanks so much.

[mtv]

ebonyblackdog, on May 11 2011, 02:56 PM, said:

Hi there -

As a new forum member I'm not allowed to post a new topic, but I just wanted some advice on the problem I'm having:

We live in Abermain (in between Cessnock and Kurri) in a 4 year old house. Antenna installed by builder - I have no idea what it is.

In 2007 we got all available digital channels perfectly, including the "Test channel" with the loop of Australian towns that one hd replaced.

Ever since ONE HD and 7Two started, we now have very unreliable reception for all channel 10 channels (5, 50, 55) and channel 7 (60, 61, 62, 63), it seemed to get worse the more channels that started. To the point it cannot be watched. 7 is slightly better than 10. It can be in any type of weather.

NBN, SBS and ABC channels are all perfect.

I managed to look at the signal strength reported by the tv and it was very low (less than 20% at times).

My questions are:
1. Does it sound like the problem is my aerial? And I should get someone to have a look at it?
2. Is it just problems inherent with these particular channels?
3. Is there something else I'm not thinking about??


Thanks so much.

If your signal levels are that low, there is probably an issue with the antenna, it's type, it's alignment or mounting location, cabling or connections.

It could be any one, or a combination of those things.

Builders don't have the required expertise to select and install TV antennas.

I've seen many builder-installed antennas which are unsuitable, or a poor choice for the area and many that have been incorrectly installed.

Without knowing exactly which antenna you have and how it's been installed and connected, it's difficult to advise, other that recommending you have it checked by a competent antenna installer, with digital signal measuring equipment.

[alanh]

ebonyblackdog,

ABHN (ABC) RF channel 37
SBS 38
NRN(Southern Cross) 51
NEN (Prime) 53
NBN 36

Southern Cross and Prime are using much higher frequencies than all other stations on Mt Sugarloaf.
It is likely that you have the wrong antenna.

Click on Get the best reception - Hunter Valley and click on the H5 link for recommended antennas.

AlanH

[ebonyblackdog]

Thanks. I will look into the antenna.you make good points.  But I do find it odd we never started having problems with 10 or prime till the new channels started.

[crownms123]

mtv, on May 11 2011, 04:25 PM, said:

If your signal levels are that low, there is probably an issue with the antenna, it's type, it's alignment or mounting location, cabling or connections.

It could be any one, or a combination of those things.

Builders don't have the required expertise to select and install TV antennas.

I've seen many builder-installed antennas which are unsuitable, or a poor choice for the area and many that have been incorrectly installed.

Without knowing exactly which antenna you have and how it's been installed and connected, it's difficult to advise, other that recommending you have it checked by a competent antenna installer, with digital signal measuring equipment.

Generally builders go for the least expensive option when installing antennas. It always seems the case of wrong antenna for location installed, incorrect equipment installed, no distribution amplifiers when needed etc..... Most of the new buildings I have been in (less than 5 years old) all had reception problems from both analog and digital. All leading from too weak a signal out of the antenna or from the outlets. This field of work should be left to the technicians who can achieve the best reception possible. That's why builders should call upon experienced installers.

[alanh]

crownms123
With the analog switchoff near the end of next year, is it still common practice for builders to get channel 3, 5A, UHF antennas in new buildings?

AlanH

[crownms123]

alanh, on May 15 2011, 01:10 PM, said:

crownms123
With the analog switchoff near the end of next year, is it still common practice for builders to get channel 3, 5A, UHF antennas in new buildings?

AlanH

AlanH,

Most of the antennas I have seen installed by builders are of the combination UHF/VHF type. Therefore, they are designed for Newcastle for both analog 3, 5a and UHF and digital so I guess it seems an easy install for them. But as experienced installers would also find that these antennas aren't adequate or correct for all areas of Newcastle for installation. For the customers I have seen using combination antennas in the areas of Newcastle that are suitable for this antenna type, there hasn't appeared to be any issues with their digital or analog reception, even if the antenna was designed for the analog 3 and 5a channels. And yes, some builders haven't been too fussed on digital installations. They just seem to install a product they think will work but may not. That is why builders should seek advice from experienced installers when antenna setups need to be done. Maybe time will tell...... When the analog reception is switched off, then builders may start to use correct installations for digital. It may seem only a small amount out of the building profits to have the correct setup for digital but may save unnecessary problems with the customer's digital reception when they move in to their new place.

Edited by crownms123, 24 May 2011 - 12:26 AM.

[ebonyblackdog]

Hi there

Just wanted to update you all. I had an antenna specialist out who installed a booster to the antenna. Our reception has improved dramatically. Worth every cent.

[BAZZARR]

ebonyblackdog, on May 26 2011, 05:37 PM, said:

Hi there

Just wanted to update you all. I had an antenna specialist out who installed a booster to the antenna. Our reception has improved dramatically. Worth every cent.

Phased Array Antenna?

Lately the ABC & SBS digital signal strength (very) occasionally drops off and I am thinking of replacing my 10 y/o UHF/VHF antenna servicing 4 wall plates which has clear line of sight to Sugarloaf tower. I understood that yagi style antennas are more suitable for clear line of sight however I am noticing quite a number of phased array (panel) antennas being installed in my Edgeworth / Cameron Park area, all with clear line of sight to the tower. I was told by one local expert that the phased array’s capability of controlling scattered signal for a cleaner stronger reception made it a better choice.
There are so many of these phased array antennas at such a wide range of prices. How can I determine my best value for money?
Or maybe I should just trim off the VHF elements, see how well the remaining UHF elements perform without them?
All thoughts appreciated

Edited by BAZZARR, 24 November 2011 - 09:43 AM.

[GlennP]

BAZZARR, on Nov 24 2011, 10:40 AM, said:

Phased Array Antenna?

Lately the ABC & SBS digital signal strength (very) occasionally drops off and I am thinking of replacing my 10 y/o UHF/VHF antenna servicing 4 wall plates which has clear line of sight to Sugarloaf tower. I understood that yagi style antennas are more suitable for clear line of sight however I am noticing quite a number of phased array (panel) antennas being installed in my Edgeworth / Cameron Park area, all with clear line of sight to the tower. I was told by one local expert that the phased array’s capability of controlling scattered signal for a cleaner stronger reception made it a better choice.
There are so many of these phased array antennas at such a wide range of prices. How can I determine my best value for money?
Or maybe I should just trim off the VHF elements, see how well the remaining UHF elements perform without them?
All thoughts appreciated

Just before you go spending money & wasting time, what do you mean by the ABC & SBS strength drops off?
Does it drop a little bit & you get pixelation or does it drop right off & you get "No Service/Reception" message?
When it drops has it been in fine hot weather or rainy weather (storms, light rain heavy rain)?

[alanh]

Bazzarr,
Read the first post in this strand.
If you have a clear view of the transmitter then an amplifier is a poor idea. You are more likely to have problems with too much signal than too little.
You need a band 5 Yagi-Uda antenna.

You also need to check the cable as well. It needs to be in good condition. No splitting or corrosion.

AlanH

Edited by alanh, 24 November 2011 - 10:37 AM.

[nbound]

Correct me if I'm wrong, but aren't those suburbs within several kilometres as the crow flies of Mt Sugarloaf? Mt Sugarloaf has quite powerful transmitters and if your that close you almost definitely wont be having any problems with lack of signal.

Its far more likely to be a physical fault (cabling/splitter/aerial), or even too much signal! Considering your location.

A yagi is generally best choice for line of sight, a phased array will work but there is no need to pick up "scattered signals" so close (when you can clearly see the thing) and they have other problems*





*This all said I have seen phased array makes signals with line of sight but nearby interference work better than a yagi. This is very unlikely to be your problem.

Edited by nbound, 24 November 2011 - 05:37 PM.

[bellotv]

BAZZARR, on Nov 24 2011, 10:40 AM, said:

.....How can I determine my best value for money?.....
All thoughts appreciated

You have asked so many questions and have been offered many possible answers.

Best way to find out whats wrong  AT YOUR PARTICULAR PLACE is to get out an antenna installer that has a digital meter.

[GlennP]

bellotv, on Nov 24 2011, 07:09 PM, said:

You have asked so many questions and have been offered many possible answers.

Best way to find out whats wrong  AT YOUR PARTICULAR PLACE is to get out an antenna installer that has a digital meter.

I'd asked the question but it hasn't been answered yet, but the reason I asked what I asked is, I don't think he actually has any problem.

His residence is reasonably close to the TX site (about 6.5km). ABC & SBS are on channels 37 & 38 respectively, NBN on channel 36 is also TX'd from the same tower/antenna array, so the likelihood of both ABC & SBS occasionally dropping out of late, would likely mean problems with NBN too, but no mention of that.

Being that close to the TX site but at a much lower altitude could also mean during the recent very hot weather, the signals are refracting over the top of him, but then he'd have troubles with all channels.

ABC & SBS digital TX's at Mt Sugarloaf are both fed off satellite using the same receiving dish & often drop out during very heavy rain (of which we've had some during storms over the past few weeks/recently), ABC seems to drop out more than SBS, but both do it. ABC & SBS analogue are TX'd from the adjacent site/tower & also fed off satellite, but using a different receiving dish & off a different satellite, & are usually ok if you switch back to analogue when the digital signals drop out.
When the ABC or SBS loses the sat. feed, you lose reception & get a no reception or no service message on the screen, the TX is still going & at full power during these times, just with no data info on it, so if you look at your signal levels on the TV you will have strong signal strength but very little or no signal quality, thus the reason I asked does it just pixelate or drop right off, & is it during high heat or rain periods.

If it's during high heat, a phased array will help capture those lower power scattered signals that aren't going over his head, if it's during heavy rain & the TX is dropping out, the Parks Radio Telescope Dish isn't going to help him.

[dbrmuz]

GlennP, on Nov 25 2011, 08:25 AM, said:

If it's during high heat, a phased array will help capture those lower power scattered signals that aren't going over his head, if it's during heavy rain & the TX is dropping out, the Parks Radio Telescope Dish isn't going to help him.

[BAZZARR]

dbrmuz, on Nov 25 2011, 10:47 PM, said:

Wow!! Such a great forum! All responses are very much appreciated.
The ABC/SBS signal lapses occur very occasionally usually in the early morning or in very poor weather and last for an hour or two, showing pixelation or dropping right off with the "no service/reception" message.
You’ve made it clear to me now that I really don’t have a problem.
I’ll just go ahead & check the cable & its connections.
I think I’ll also remove the now unnecessary VHF elements. One of which has been half broken by an overfed dove. Are there any traps with removing these elements?
Many thanks for all the help.

[nbound]

BAZZARR, on Nov 26 2011, 07:41 AM, said:

I think I’ll also remove the now unnecessary VHF elements. One of which has been half broken by an overfed dove. Are there any traps with removing these elements?
Many thanks for all the help.

Its not going to make any real difference difference to the UHF reception.

BAZZARR, on Nov 26 2011, 07:41 AM, said:

Wow!! Such a great forum! All responses are very much appreciated.
The ABC/SBS signal lapses occur very occasionally usually in the early morning or in very poor weather and last for an hour or two, showing pixelation or dropping right off with the "no service/reception" message.
You’ve made it clear to me now that I really don’t have a problem.
I’ll just go ahead & check the cable & its connections.

But if by poor weather you mean rain/dew, you could actually have a problem.

Edited by nbound, 26 November 2011 - 07:25 AM.

[BAZZARR]

nbound, on Nov 26 2011, 08:20 AM, said:

Its not going to make any real difference difference to the UHF reception.


But if by poor weather you mean rain/dew, you could actually have a problem.

I'm not certain about the degree of poor weather. I'll pay better attention next time the reception fails.
Should the problem occur due to rain/dew what would be the solution?