635 replies to this topic

[alanh]

nbound,

Hyperband channels are;
S11 230 - 237 MHz
S12 237 244 MHz
through to
S44 463 - 470 MHz
"Channel 20" 470 - 477 MHz
through to
"Channel 27" 519 - 526 MHz

In digital Hyperband channels are reserved for DVB-C or DVB-C2 which are used for cable receivers.

In all other DVB-T/T2 countries 470 - 526 are their channels 21 - 27 which are used for TV.

AlanH

Edited by alanh, 05 May 2012 - 12:42 AM.

[cottrent]

I am looking for some help.......

Approx 6 weeks ago I temporarily (ie for 30mins max) lost ABC digital channels so I re-tuned my tv.  On re-tuning, I had lost the SBS digital channel/s and no matter how many times I have re-tuned, I have never got SBS digital back.  I had had it happily before that.

I have been on the roof to look at the antenna and all looks ok, with nothing loose.  It is a substantial looking antenna (well, comparing it to the houses next door!).

I have also been in contact with SBS Technical who advised me to get out a antenna technician but I was hoping to avoid this unless all really does point to a faulty antenna.

I am in Cottesloe but approx a mile back from the beach and it doesn't look I am in a blackspot.

Has anyone got any thoughts of what I can do to get SBS digital back?

[M'bozo]

Has anyone got any thoughts of what I can do to get SBS digital back?

Assuming that you have been using the TV's automatic tune function, I would try a manual tune for SBS, to see if this restores the station.

If this is not successful, you can look further afield.

[nbound]

alanh, on 05 May 2012 - 12:29 AM, said:

In digital Hyperband channels are reserved for DVB-C or DVB-C2 which are used for cable receivers.

And yet Ive digitally modulated on these frequencies and received them on TVs (as a test). Hyperband isnt just used for cable/DVB-C, and the same was true for analog hyperband.

But regardless, we are far far far far off topic, and theres not much point going on, so I wont be continuing this discussion.

Edited by nbound, 05 May 2012 - 08:35 AM.

[nbound]

cottrent, on 05 May 2012 - 02:22 AM, said:

I am looking for some help.......

Approx 6 weeks ago I temporarily (ie for 30mins max) lost ABC digital channels so I re-tuned my tv.  On re-tuning, I had lost the SBS digital channel/s and no matter how many times I have re-tuned, I have never got SBS digital back.  I had had it happily before that.

I have been on the roof to look at the antenna and all looks ok, with nothing loose.  It is a substantial looking antenna (well, comparing it to the houses next door!).

I have also been in contact with SBS Technical who advised me to get out a antenna technician but I was hoping to avoid this unless all really does point to a faulty antenna.

I am in Cottesloe but approx a mile back from the beach and it doesn't look I am in a blackspot.

Has anyone got any thoughts of what I can do to get SBS digital back?

M, on 05 May 2012 - 05:34 AM, said:

Has anyone got any thoughts of what I can do to get SBS digital back?

Assuming that you have been using the TV's automatic tune function, I would try a manual tune for SBS, to see if this restores the station.

If this is not successful, you can look further afield.

Assuming you are receiving from the main Perth Transmitter (your antenna should be roughly pointing towards Como from Cottesloe), then you want to perform a manual scan on CH29.

Also check your TV hasnt stored the station in the 350+ range. Might be worth doing a factory reset as well, and full retune after that.

It is possible there is some kind of fault with your aerial system, and the ABC has returned to a usable state, but with a lower signal quality or strength (enough to be over the digital threshold - so is fine to watch), while SBS hasn't faired so well, Are you receiving the community station?

Failing the above, then call out a technician.

[alanh]

The usual load of twaddle.

Manually tuning the receiver has little effect because if the auto mode does not work, it has insufficient signal to detect the pilot signals required for demodulation and cause the fine tuning to work. If the signal is that weak it will not be reliable.

At this time of year it is not possible to receive SBS channel 34 from Bunbury which would have become channel 350+

Cottesloe will be covered by new translators to be installed on Observation City which will fix his reception for all channels. It should be on air by the end of the year. This transmitter is for the black spots all along the coast. This will require a small UHF antenna.

If you are trying to get your signal from Bickley SBS will be moved from channel 29 (UHF) to channel 7 in the last half of next year. Digital channel 7 uses channel 6.

In the meantime,

The main thing to look for is corrosion and water into the top of the cable. Now that the rain has commenced after such a long period of dry the water may be still there.

Also check for wind damage causing bending of the elements protruding from the thick boom.

Read the first pinned post in this strand.

AlanH

Edited by alanh, 06 May 2012 - 12:44 AM.

[hrh]

alanh, on 06 May 2012 - 12:41 AM, said:

The usual load of twaddle.


Cottesloe will be covered by new translators to be installed on Observation City which will fix his reception for all channels. It should be on air by the end of the year. This transmitter is for the black spots all along the coast. This will require a small UHF antenna.

If you are trying to get your signal from Bickley SBS will be moved from channel 29 (UHF) to channel 7 in the last half of next year. Digital channel 7 uses channel 6.

In the meantime,

The main thing to look for is corrosion and water into the top of the cable. Now that the rain has commenced after such a long period of dry the water may be still there.

Speaking of twaddle, saying what is going to happen by maybe the end of this year and sometime next year doesn't address the current situation. The poster has also said that as far as they can ascertain the antenna looks OK. And it all happened about six weeks ago, well before any rain.
There is the possibilty that someone nearby (like next door) has got something that is causing RFI sufficient to degrade the signal - I've had that happen caused by a neighbours outside light which had a compact fluorescent globe in it and everytime it was swtiched on my reception of ABC and Ten digital went to the very edge of the cliff and sometimes over it.
I would go along with nbound's suggestion of failing all else...

[cottrent]

Many thanks.

I have tried a manual re-tune (536.625) but it only comes up with a message saying "0 channels are memorised."

I am pointing towards Como.

I have done a factory re-set (well, at least a re-set and I think it was a factory re-set - hunted Samsung user manual and their website for the little nugget buried deep down saying to put the tv on Standby and then hold the Exit button down for a number of minutes and, sure enough, it started everything, including plug and play tuning.)

I am not receiving the community channel......

ABC is in a usable state - all the ABC channels show as SD channels except ABC24 which shows has HD (with the little visual LED meter, that comes up on selecting a channel, showing as half full for all ABC channels).  I have not tested the aerial cable that goes from the wall directly into the tv - I will do that by borrowing one and seeing if that changes anything.

It does not appear that SBS is stored in the 350+ range - certainly not showing up in any (channel) lists.

The only other point to make is that my tv is from the UK......cannot see how that would make a difference considering I have had SBS on it before but I have put a query out to Samsung regarding not being able to choose 'Australia' in the country drop-down menu (it only lists European countries).

[cottrent]

I will get back up and have a look, esp. for wind damage. (I had noticed another transmitting station coming on-line as the notice comes up on the digital tv map saying that the signal will be coming from a new station.  I had wondered if this already had something to do with my predicament but clearly not if is not yet transmitting)

I did wonder if the neighbours' set-up would have anything to do with anything as I lost the channels when new, (young). folk moved in next door after the little old lady moved out.  Pretty much well around the same time.  I note ages as one would assume that young people have up-to-date technology.  I have no idea what or how or what I could do about it.

[M'bozo]

The only other point to make is that my tv is from the UK......cannot see how that would make a difference

Yes it does.

not being able to choose 'Australia' in the country drop-down menu (it only lists European countries)

What country have you selected: West Germany?

This will allow reception of some local VHF channels, as some of their channel frequencies line up with ones transmitted from the main Perth site.

Plus, the channel width is the same as Australia, (7MHz), however, post analogue switch off, you may be in strife with the reception of some channels, due to VHF frequencies not aligning.


UHF channels have 7MHz spacing in Australia, 8 MHz for Western Europe, and the channel frequencies don't line up either. I'm surprised your set could even tune SBS previously, let alone decode it.

I note you can manually input channel frequencies. Without knowing the model number of your TV, do you have the option in manual tune of setting the channel bandwidth? If you do, set it for 7 to see if this helps.

I have put a query out to Samsung

Forget it. They can't help. Only solution, if there are no others, and assuming no fault with your reception system, is to get an external set top box.*

*Assuming your not using one already.

I did wonder if the neighbours' set-up would have anything to do with anything as I lost the channels when new, (young). folk moved in next door after the little old lady moved out. Pretty much well around the same time.

While possibly relevant, I'd be thinking probably not. Only way to be sure is get a competent antenna tech out, if all else fails.


Edit: Correct oversight.

Edited by M'bozo, 06 May 2012 - 08:01 AM.

[nbound]

alanh, on 06 May 2012 - 12:41 AM, said:

The usual load of twaddle.

Manually tuning the receiver has little effect because if the auto mode does not work, it has insufficient signal to detect the pilot signals required for demodulation and cause the fine tuning to work. If the signal is that weak it will not be reliable.

Oh Alan

If you actually did this stuff from day-to-day you would see all kinds of strange ****, Ive seen tvs tune previously untunable stations doing just what I suggested more than once, yes Im aware it goes against the theoretical side, but occasionally be it due to a bug in the firmware, or the tuner gods having a bad day, strange things work. Though most importantly its something he can try himself, its not going to make the problem any worse and at the very least the tv may have a quality/strength meter which may hint at the issue (eg. "I noticed the strength bar dropping whenever there was a strong gust of wind").

Also if there is cabling issues due to water or wind, then the cause may have gone, and the channel may tune ok (but drop out in future), in which case it strongly narrows down the causes.

alanh, on 06 May 2012 - 12:41 AM, said:

Cottesloe will be covered by new translators to be installed on Observation City which will fix his reception for all channels. It should be on air by the end of the year. This transmitter is for the black spots all along the coast. This will require a small UHF antenna..

If you are trying to get your signal from Bickley SBS will be moved from channel 29 (UHF) to channel 7 in the last half of next year. Digital channel 7 uses channel 6.

None of this fixes his problem now, and as he previously had usable reception from Perth Transmitter, he should try and fix it, instead of going without some stations for months just to save a few bucks on a smaller antenna! If 10 years down the track something goes amiss, then sure swing for the new transmitter.

cottrent, on 06 May 2012 - 02:43 AM, said:

Many thanks.

I have tried a manual re-tune (536.625) but it only comes up with a message saying "0 channels are memorised."

I am pointing towards Como.

I have done a factory re-set (well, at least a re-set and I think it was a factory re-set - hunted Samsung user manual and their website for the little nugget buried deep down saying to put the tv on Standby and then hold the Exit button down for a number of minutes and, sure enough, it started everything, including plug and play tuning.)

I am not receiving the community channel......

Well there appears to be an issue with the UHF signals you are receiving (and after reading ahead - Its due to the UK TV)

cottrent, on 06 May 2012 - 02:43 AM, said:

The only other point to make is that my tv is from the UK......cannot see how that would make a difference considering I have had SBS on it before but I have put a query out to Samsung regarding not being able to choose 'Australia' in the country drop-down menu (it only lists European countries).

Is there an option to change Bandwidth? Unlikely on a Samsung, but if its there it should be set to 7Mhz. The other thing to try is that some sets have a generic country option usually called "Other" or something similar, YMMV with that though.

If SBS was tuned on this set previously, perhaps a technician can find what setting has been changed. He could also check if the station is tunable/watchable on his own signal meter/portable tv. And as M'bozo has suggested, try and find if the neighbours are the cause (unlikely)

Otherwise as M'bozo has suggested, a Set-top-box is the way to go.

Edited by nbound, 06 May 2012 - 03:36 PM.

[alanh]

My comment about new transmitters was to stop him spending a lot on the antenna system when a very small and inexpensive antenna will be all that is required in less than 7 months time.

Since the receiver worked before, the most likely cause is an antenna system fault, hence my comment about water in the cable & corrosion.

1. The selection of a mainland European country  will allow VHF channels which it is already achieving and would never have received SBS or West TV.
The European band 3 channels are identical to ours except for names their channels 5 - 8 we call channels 6 - 9. Channels 10 - 12 are absolutely identical.

Remember it did! He manually tuned the receiver to the offset frequency to no joy disproving this theory. Without being able to select 7 MHz bandwidth and or a lack of UHF signal is causing SBS to have "no signal". I expect that the initial scan of the receiver the SBS the signal was much stronger than now. The receiver has to tune a channel 1.5 MHz higher than it would expect.

2. RFI is unlikely to be the problem because it has the least effect at UHF so should have affected the commercials as well. In addition if the compact fluro was a problem it is likely to be off during the day. As you said it only affected VHF channels.

3. Since the system was working ok until now the most likely cause is an antenna system failure The location he is in is subject to strong winds and lots of salt sea spray. We do not know what type of antenna is in use, is it designed to receive channel 12. This is what I have said from the start.

There are areas of lower signal strength in Cottelsoe which is part of the reason for the new translator.

Now that we know about the UK TV, an HD set top box or a PVR will be required for reliable reception of the translator signals he may as well buy one. This will prove if there is an antenna system fault.

AlanH

[nbound]

alanh, on 06 May 2012 - 06:54 PM, said:

My comment about new transmitters was to stop him spending a lot on the antenna system when a very small and inexpensive antenna will be all that is required in less than 7 months time.

The thing is you dont know that anyway, its going to depend on whats between him and the new site. He could be in a poor spot for it, and a great spot for Perth transmitter.

If he has line of sight to the new site, and if he doesnt mind going without stations for an extended period, and if his set is going tune it again, then perhaps the new site is an option, but most people dont want to go without stations for any longer than they have to. The new infill transmitter is unlikely to be carrying West TV either which is something to keep in mind.

alanh, on 06 May 2012 - 06:54 PM, said:

Since the receiver worked before, the most likely cause is an antenna system fault, hence my comment about water in the cable & corrosion.

3. Since the system was working ok until now the most likely cause is an antenna system failure The location he is in is subject to strong winds and lots of salt sea spray. We do not know what type of antenna is in use, is it designed to receive channel 12. This is what I have said from the start.

Now that we know about the UK TV, an HD set top box or a PVR will be required for reliable reception of the translator signals he may as well buy one. This will prove if there is an antenna system fault.

AlanH

We've all said theres a good possibility of antenna/cabling issues. Infact i suggested it in the post before yours.
Without adequate measuring equipment, his cheapest option is to grab a cheap STB, hook it up, if all stations tune - great - connect to UK TV set by HDMI. If still no UHF, then call in a tech and get the problem sorted quickly, or he can have a go himself (if hes able to ascertain the actual cause).

alanh, on 06 May 2012 - 06:54 PM, said:

2. RFI is unlikely to be the problem because it has the least effect at UHF so should have affected the commercials as well. In addition if the compact fluro was a problem it is likely to be off during the day. As you said it only affected VHF channels.

Impulse noise has less effect at UHF.
RFI can occur at any frequency depending on the source, faulty gear that operates in the space below 28 could easily cause interference into Band 4. Needless all of us have stated this is a very unlikely scenario despite the fact he's tied the failure point to them moving in (ie. coincidence).

[cottrent]

Righto.  I am getting the sense to first try a set-top box (which I have already got my hands on one - just need the correct cables) and if that fails, it is v possible it is the antenna.  I didn't get on the roof today to review the antenna again as the weather was inclement but will perhaps tomorrow, all being well.

I can choose either 7 or 8Mhz and...........................whoooooaaaa, I have manually tuned in 536625 using 7Mhz (the TV defaults to 8 and I, not having any idea of what it means, have never changed it) and I have ALL the SBS channels.  Cannot believe it.  I am really thrilled and many, many thanks for all your input.  When I say ALL, 7 instances of SBS channels have appeared!  Never rains but it pours.

I presume I must take away that there is a weakness in my set-up which I must be mindful of when the signal will start to be sent by Scarborough.

PS:  wrote it in pink as you can refer to me as a she, not a he!!

Many, many thanks to all.

[hrh]

alanh, on 06 May 2012 - 06:54 PM, said:

Since the receiver worked before, the most likely cause is an antenna system fault, hence my comment about water in the cable & corrosion.

And my comment about no rain back then tends to rule that out - go and have a look at the rain recorded for March at Swanbourne.

Quote

...if the compact fluro was a problem it is likely to be off during the day. As you said it only affected VHF channels.

That was for my case and not necessarily the case for all CFLs if they should have cause to create enough RFI - others may affect different frequencies.
As far as likely to be off during the day, possibly for we older generation types who were taught/told to turn things off it may be the case but for Gen Y and Z they tend to not turn things off. The young couple next door on the other side to where the offending light was, have a strong tendency to leave their outside lights on at all sorts of times day and night, and they aren't on a timer.

cottrent, on 06 May 2012 - 08:30 PM, said:

and I have ALL the SBS channels.  Cannot believe it.  I am really thrilled and many, many thanks for all your input.  When I say ALL, 7 instances of SBS channels have appeared!  Never rains but it pours.
any thanks to all.

Congrats, well done.

[M'bozo]

I have manually tuned in 536625 using 7Mhz

As I expected you probably would.

Being able to select the channel frequency, suggested to me the bandwidth could also be selected.

Once again, experience gained as an installer of antennas, & associated equipment, allowed an insight to solving your issue.

[nbound]

cottrent, on 06 May 2012 - 08:30 PM, said:

I can choose either 7 or 8Mhz and...........................whoooooaaaa, I have manually tuned in 536625 using 7Mhz (the TV defaults to 8 and I, not having any idea of what it means, have never changed it) and I have ALL the SBS channels.  Cannot believe it.  I am really thrilled and many, many thanks for all your input.  When I say ALL, 7 instances of SBS channels have appeared!  Never rains but it pours.

Good work, then you should be able to get West TV aswell (CH32, 557.5MHz)

Props to M'bozo for first suggesting the fix

cottrent, on 06 May 2012 - 08:30 PM, said:

PS:  wrote it in pink as you can refer to me as a she, not a he!!

Oops, sorry bout that!

(I think it was from ur handle containing the word "trent", but now i see it as "cott"esloe "rent"ers, or something along that vein?)

Edited by nbound, 06 May 2012 - 09:27 PM.

[cottrent]

M'bozo, I do thank you.  It was you who first suggested it.  I even went to your profile to see who you were and was astounded; a 7-year-old!  Makes me feel ignorant and old......

nbound, you are quite the sleuth on my handle - and quite right - just not the plural reference.

Cannot say again how pleased I am.  I dislike intensely my electronics not working to their full capacity and I was most loath to spend money to get some chap out only to tell me it was NOT the antenna.

[nbound]

cottrent, on 06 May 2012 - 09:46 PM, said:

M'bozo, I do thank you.  It was you who first suggested it.  I even went to your profile to see who you were and was astounded; a 7-year-old!  Makes me feel ignorant and old......

Im not sure his profile is entirely accurate (He's been installing antennas for over 40yrs)

Edited by nbound, 06 May 2012 - 09:51 PM.

[cottrent]

hee hee.  I did gather his large experience was inconsistent with his age.

[M'bozo]

Plus, the channel width is the same as Australia, (7MHz), however, post analogue switch off, you may be in strife with the reception of some channels, due to VHF frequencies not aligning.

Hmmm, probably wrong about this.

Looks like the range of frequencies for sets of this ilk is 174 - 230MHz, 470 - 862MHz, so should be OK for a manual tune after analogue switch off.

[M'bozo]

a 7-year-old!

This relates to the time since starting to contribute here.

My real age may be approximated by stating that, under current rules, I do not qualify for an age pension until attaining 65.5 years.

[cottrent]

ha!  got it.

[alanh]

The wash-up is;
"Approx 6 weeks ago I temporarily (ie for 30mins max) lost ABC digital channels so I re-tuned my tv".

The original problem was either there was either a reception problem a the viewer's location or a transmission fault.'
We do not know what antenna is in use. It may not be designed for the channel 12 used by ABC digital. There is a digital cliff where you get a perfect signal, breaks up on picture and sound or you get nothing. A small drop in signal strength the reception can go from perfect to nothing.

On the original set up on this site the UHF to 7 MHz channel width must have been set. Either the channel width was accidently set to 8 MHz or a factory reset was created by following the manual. This now means that all commercials and the ABC can be tuned and not SBS or West TV. As I pointed out recently in this strand that band 3 European and Australian channels are identical except for the names.

For a non imported TV the usual cause is a poor antenna signal. Digital TVs use a crystal as a frequency reference to ensure the frequency does not drift. Where has the "automatic fine tuning" gone? That's why it is not required. DTVs designed for the Australian market only have to deal with the correct channel frequency or a 125 kHz shift which will not be required after the analog switch off. This will probably be removed during the digital restack. STW channel 8 (Nine Network) and SBS are the only stations using this shift in Perth. I note he has no problem with STW so his receiver can easily cope with this offset.

The manual tuning of SBS to its actual frequency did not work because the bandwidth setting was too wide.

There was no LCN 350+ because there is no other SBS within range.

The recommendation of doing a factory reset made sure that the 8 MHz UHF bandwidth was selected as a European/UK default.

At this point there was no mention of an imported TV.

nbound,
About tuning untuneable channels in the east there is many more transmitters along with many translators. The number is increasing as the switchover moves on.
Tuners over the last 10 years have improved performance over the types you describe with continuous tuning. (Frequency systhesis for one)

The new translators are not 10 years away but by the end of this year. The reason I mentioned this was to not suggest an expensive antenna upgrade for nothing. This may be required for his ABC reception anyway.

Some antenna cable has holes along its length particularly older types. Water is unlikely to rapidly evaporate and considering loss increases with channel number SBS & West will be most affected.

You have no idea of what will happen to community TV. The Minister has not announced the policy. I doubt they will want to buy a channel 10 transmitter having just forked out for a number of UHF transmitters. I say this because it is possible that they could increase the bandwidth of SBS transmissions leaving space for an SD community TV signal and NITV. That being the case all translator sites will get SBS so their channel 7 will be repeated on UHF like all other networks.

Besides the above cottrent may not miss West TV because I has not seen it yet!

So the initial ABC reception problem is unresolved and if not a transmitter fault indicates an antenna system fault which was aggrevated by the incompatiblity of European to Australian UHF channels.

Alanh

[nbound]

alanh, on 07 May 2012 - 09:09 PM, said:

The new translators are not 10 years away but by the end of this year. The reason I mentioned this was to not suggest an expensive antenna upgrade for nothing. This may be required for his ABC reception anyway.

And the reason, I suggested against this is that people dont want to go without TV. Yet when these threads pop up, you say "post restack you'll only need blah", or "wait for x months and you can get reception from blah". In the real world, you could say that to a customer, and almost 100% of the time they would give you a look as in "are you ****ing serious? - what am i to do until then! (and give me my money back!!!)". Yes the recommendations you are saying arent factually incorrect in this case, but they arent realistic either.

We dont know if there is a problem with the aerial/cabling either, and the only thing (other than a visit by a tech) that will prove otherwise is continued usage.
While Im not familiar with WA tenancy laws, any repairs are likely an expense to be paid for by the landlord.

alanh, on 07 May 2012 - 09:09 PM, said:

Some antenna cable has holes along its length particularly older types.

Another Alanh factoid - Yes I spend half my days removing it, Im well acquainted.

alanh, on 07 May 2012 - 09:09 PM, said:

You have no idea of what will happen to community TV.

And neither do you, so the point is... ?

alanh, on 07 May 2012 - 09:09 PM, said:

Besides the above cottrent may not miss West TV because I has not seen it yet!

Maybe, but most people want all the stations available, regardless of how often they watch them, choice is king. I never suggested against it on that basis, just to keep it in mind that it wont be available.

alanh, on 07 May 2012 - 09:09 PM, said:

So the initial ABC reception problem is unresolved and if not a transmitter fault indicates an antenna system fault which was aggrevated by the incompatiblity of European to Australian UHF channels.

And again, we dont know whether there was a problem or not, only usage (or a tech visit) will show us if there was or wasnt.