Insane need to maximise analogue equipment

[Griffin NoName]

Analogue TV reception in our block of flats is unwatchable as I have doubtless mentioned before.

It's poor consistently, but every time a new owner moves in they erect their own aerial on the roof and the communal aerial reception worsens into garbage. Several flats suffer as they dont have satellite, cable or freeview and depend only on the communal aerial. Not surprisingly new owners who erect their own equipment deny any culpability and the "evidence" is therefore circumstantial.

Each time the management company pays for dodgy aerial people (a different lot each time in an ever optimistic view that they may know what they are doing). The reception improves slightly but not enough to br viewable.

We've been given every excuse to explain the problem. Like the tree which is actually lower than the aerial and must have magic powers.

The problem is slightly academic as we are due to switch to digital in 2008 but we don't like being fobbed off so we keep trying to get it fixed.

The latest fiasco is yet another newbie installed their own aerial and the communal aerial is even more useless than ever before.

I found a recommended company and they visited last week. They confirmed the tree is a red herring and said that they couldn't find the transducer and needed to unravel the wiring in the whole building.

From the aerial a wire for each flat disappears down into the central service cavity wich is a vertical cavity for the block for all services.

Without knowing much about TV wiring (I know and understand the basics) I was slightly puzzled, thinking that if there were a transducer it would be at the point where the incoming signal was split (there's a booster and a splitter) into separate wires for each block. So I was not convinced by them saying they'd have to get down into the central cavity in which there are individual wires for each flat. It sounded like it might be a money spinner (I wasn't involved in their inspection and the guy was is totally non-technical and so unlikely to have asked them any leading questions).

I decided to see if there were any wiring diagrams for communal aerials but I can't find any.

What I did find were plenty of statements "An antenna or aerial is a transducer designed to transmit or receive radio waves which are a class of electromagnetic waves. "

This would suggest they couldn't find the aerial. The aerial being the transducer? This makes no sense as all the other previous cowboys claimed to have "fixed" the aerial (and something is receiving good digital signals). Sadly I am not fit enough to go up on the roof myself to see what's what. So now I am confused, puzzled, and not knowing how to sort it out..... (me being the resident "person who knows how to....").

Can anyone make sense of this?  (there is a general wish not to wait til analogue is dropped in 2008).

[beagle]

Not really an expert on this. As far as I know the important factors are (in aproximate importance).

In range of transmitter.

Not being in shadow of hill or other building.

Aerial pointing at transmitter (degree or so off makes big difference).

Not getting bounced signals off other buildings.

Right type of aerial.

Good quality amplifier close to the aerial.

Good quality cable i.e. screened (not the old-fashioned "low loss coax"). I think CT100 is the name of the good stuff, but wouldn't swear to it being appropriate.

Avoid splitting the signal as much as possible.

Avoid running cable past lift motors, fluorescent lights etc.

Don't know what they mean by transducer (but as I said, am no expert).

You can generally find junctions in cable using a device called a Time Domain Reflectometer (like radar down a wire, it tells you the distance from which some signal has been reflected). When I used them they cost tens of thousands and only airline/military technicians tended to have them, but I think they're standard kit for anyone in networking etc these days.
That might localize which floor to start looking at.

[Griffin NoName]

In range of transmitter.  It is. All engineers who have looked at it, except this latest lot who have said nothing except "transducer", say reception at aerial on roof is excellent.

Not being in shadow of hill or other building. It isn't.

Aerial pointing at transmitter (degree or so off makes big difference). Assume it is as reception good (see above)

Not getting bounced signals off other buildings. Assume it isn't. See above.

Right type of aerial. It must be. See above.

Good quality amplifier close to the aerial. There is.

Good quality cable i.e. screened (not the old-fashioned "low loss coax"). I think CT100 is the name of the good stuff, but wouldn't swear to it being appropriate. I bet it's low loss coax. Building is 1970's. Original wiring.

Avoid splitting the signal as much as possible. Been some suggestion it might be. But don't know how to find out how much is too much.

Avoid running cable past lift motors, fluorescent lights etc. The wires all run down cavity next to lift. Original design feature.

Don't know what they mean by transducer (but as I said, am no expert).

The transducer argument is the latest idea and this lot of engineers wont do anything more unless we pay them to find it. That's the problem. Not knowing if it's yet another fancy idea to get paid for old rope. 

You can generally find junctions in cable using a device called a Time Domain Reflectometer (like radar down a wire, it tells you the distance from which some signal has been reflected). When I used them they cost tens of thousands and only airline/military technicians tended to have them, but I think they're standard kit for anyone in networking etc these days.
That might localize which floor to start looking at.

The junction must be on the roof. The cables are all individual by the time they run down the floors. All floors are affected. Another reason why I am wondering why the engineers want to start unravelling each floor.

If it's bad wiring, then wiring to each floor would need replacing. But that's a different thing to finding a transducer and they aren't suggesting that the wiring needs replacing.

Thanks for the breakdown. I just wish I could get up there and look myself. I have a feeling we've hit a dead end as usual. Fobbed off. We've had so many engineers come look over two-three years all with different theories I suspect it will be 2008 and we will still be no wiser.

[beagle]

I doubt you'd be able to deduce much (unless the aerial has been pinched or the cable is obviously decayed and letting in water - very not good). You need someone with the equipment to inject a signal after the amplifier and measure how much survives n floors down, IMHO.
If that's all right then the amplifier on the roof might need kicking hard.

If an injected signal doesn't make it through the building then either the cable needs replacing/re-routeing or there's another amplifier en-route not doing its job.

(All in my non-expert humble opinion).

[Griffin NoName]

You need someone with the equipment to inject a signal after the amplifier and measure how much survives n floors down, IMHO.

We need someone who knows stuff. But I don't know how to find such a person. This latest lot came recommended by John Lewis in Oxford Street which I thought was a brainwave, but seems no better than the yellow pages.

When you call any of the TV aerial companies, what you get is a couple of young lads, never ever the boss or anyone who seems remotely experienced other than in bog standard.

What you say, about the signal makes sense, but how to find anyone equiped and knowledgable enough to do that, because I don't think it's going to be under TV aerial people listings?

Keep wracking my brains through all my old techie contacts but most of them seem to have retired to Spain. Spain may have some of the best wiring in the world.

[Sibling Lambicus the Toluous]

Just to be clear, the problem affects everyone on the antenna equally, right?

For an outdoor antenna, my first suspects for poor performance would be:

- water or corrosion (as beagle mentioned)
- vermin, i.e mice, etc. chewing on the cable
- damaged cable.  Does the cable have any spots where it's flexed often, pinched or subject to friction?
- poor antenna ground
- damaged antenna.  It isn't visibly bent, is it?  No missing parts?

All of these should be in the forefront of the mind of anyone looking at a bad antenna, so if you've had people in, hopefully all this would have been checked out.

One thing I thought of, though: if they've only been checking for continuity with a multimeter, a flaky cable could seem okay.  If nobody's used one before, checking point-by-point with a proper antenna analyser (or a similar idea - what I think of as an "antenna analyser" is for transmitting antennas) might find the problem.

[Griffin NoName]

Thanks Lambi.

My problem is finding any company that actually provides this kind of level of service.

[Sibling Lambicus the Toluous]

How about the "check the antenna itself, then check at each point downstream in order" level of service?   

[Griffin NoName]

That goes back to this lot want to search for a transducer. Until we know why, and whether they should be doing something other than simply searching for a transducer, the Treasurer wont pay for that. Can you explain what they mean by needing to search for a transducer?

[Sibling Lambicus the Toluous]

Not a clue, though I don't have experience splitting an antenna signal between many receivers.

I always thought that a transducer is a device that changes energy from one form to another (usually to electrical energy), so the antenna itself would be a transducer.  Dunno what they're referring to in this case, unless it's a signal amplifier, or the splitter.

[Griffin NoName]

Well that confirms what I think.

It's not the signal amplifier, that's visible on the roof; it's not the splitter either, ditto. And they've been checked a million times.

I checked out what a transducer is and concluded it is actually the aerial.

Now if they can't find the aerial, which everyone else has found, they need to explain why they can't find it. It's on the roof with the amplifier and the splitter and it receives a good signal !!

So what I think is we have yet another lot of cowboys, which is what we have had roughly six times already. Expensively.

No wonder the Treasurer wont pay anyone any more. Especially as this lot were given clear instructions as to what we needed them to do. Having built up a fair amount of knowledge ourselves along the way.

Part of the problem is that I can't get up on the roof myself and these guys run rings round the Treasurer as he has no technical knowledge (I can't even get him to understand that digital TV is different to analogue - he along with millions is going to have tough time in 2008).

All of which leaves me needing to find people who know how to do more than check the obvious and don't need me up on the roof to make them do it. Or crawling in between floors!

And... I can't find anyone. <sigh> or I haven't cracked the correct Google search.

[ivor]

I'll bet it's the wiring.  The wiring would cost a lot to replace and the management company doesn't want to spend it.  The management company just keeps bringing inept people out to make it look like they are doing something.

[Bluenose]

Antennas and cabling are my thing, been an amateur radio operator for 30+ years, although not very active the last few.

Anyway, the only way to sort this out is to start at the antenna and then work your way down.

If you get a good picture directly from the antenna, then the next step is the amplifier.  See if you get a good signal directly from one of the outlets from the distribution amp/splitter.  My bet is its the amp/splitter.  It is unlikely that the distribution cabling is all faulty.  If you are sure that each unit has its own cable running up to the distribution amplifier/splitter then at least some of them, especially those that have the shortest run would have usable signals.  The fact that they all do not says it has to be something in common with them all.

I do not know how many units are fed from this system, but I am highly suspicious of large numbers of outlets being fed from one location unless the people that are doing it really know their onions.  Without physically looking at it, it is hard to say, but if they have a separate distribution amplifier and splitter, or worse yet multiple splitters, then it is probably a design problem and the amp and splitters need to be replaced with a distribution amplifier that is designed to feed the number of outlets in your situation.  If the amplifier is not separate from the splitters, that is it is one designed for the situation, then is the amp receiving power?  These amplifiers have varying ways of receiving power, one way often used for domestic situations is to feed the power up the coax.  I cannot imagine that this has been done in your case, but if it is, maybe the person from whose apartment the power is supposed to be fed simply does not have it switched on, or they threw it away because they did not know hat it was for.  Generally I would expect a distribution amp to be mains fed, has someone switch off the relevant circuit breaker?  Is it unplugged etc?  If it does have power, then I would suspect that the distribution amp may be faulty.

Don't know if this is going to be of any help.  I wish I could just come over and have a look at it, I am sure we could find the problem in a few minutes.  But I suspect that your treasurer may not be too keen on funding a round trip from Melbourne! 

Sibling Bluenose

There is no such thing as a transducer in the manner that your cowboys are talking about.  It sounds like they have learned a nice technical sounding word that they can use to extract a lot of money from innocents abroad.

[goat starer]

Griffin, I would be glad of the excuse to prevent Mrs Goat watching the strem of garbage that comes out of our telly. can I move in?

[Griffin NoName]

I'll bet it's the wiring.  The wiring would cost a lot to replace and the management company doesn't want to spend it.  The management company just keeps bringing inept people out to make it look like they are doing something.

The Treasurer and I are the Management Company

Don't know if this is going to be of any help.  I wish I could just come over and have a look at it, I am sure we could find the problem in a few minutes.  But I suspect that your treasurer may not be too keen on funding a round trip from Melbourne! 
<snip>
There is no such thing as a transducer in the manner that your cowboys are talking about.  It sounds like they have learned a nice technical sounding word that they can use to extract a lot of money from innocents abroad.

Yes it is helpful. Although as yet I am not sure how to apply it. We fix our own service charge and so no, I think we wont be flying you out,,,,,,, shame

Thanks for confirming the transducer is cowboy speak. Good to know I know when to be suspicious..... except I wish one didn't need to be.

Griffin, I would be glad of the excuse to prevent Mrs Goat watching the strem of garbage that comes out of our telly. can I move in?

If Goats are happy with hammocks slung from the ceiling. There's no floor space left. 

[beagle]

When people put their own aerials up which work do they re-use the old wiring to their floor, and if so does it work?

Do the aerials they put up look the same as the communal antenna, i.e. pointing the same direction, the same number of elements (metal bars) in the same orientation (horizontal, vertical, cross), and do they have  reflecting plates which the communal one doesn't?

Have any of the experts actually measured the signal coming out of the aerial and/or amplifier, or are they just claiming reception is good because the other aerials work, or because their computer generated coverage map says it should be?

Just to depress you further, if the cabling is the problem then switching to digital may well not fix it. Interference that cause a momentary flash on analogue can throw the error detection so badly that digital will skip the picture entirely for two or three seconds (like when you play a DVD with a hair or bad scratch on the surface). On the plus side, once you get the error rate down to zero there's no point spending money to improve the signal strength further.

[Griffin NoName]

On the plus side, once you get the error rate down to zero there's no point spending money to improve the signal strength further. Hehe. Goodee. If ever.

The coboys have variably claimed to have actually measured the signal. Who knows.

Digital works fine. Mine used to skip the picture until I tightened up all my aerial connectors.

Mostly the people who have no problem have sat. dishes.

Some I suspect only watch digital (all the ones who report their pics are fine have sat. or digi).

The analogue viewers with bad pics are spread across all floors.

I think 1 person has an actual own "aerial" on the roof and I don't know if it was new wiring but I strongly suspect it was. No point asking them as they wouldn't have a clue. 

No one has a clue round here. Except me. And I have so many they cancel each other out.

[beagle]

I'm guessing the people who have satellite either have their own high quality cable to roof dishes, or the dishes wall mounted outside their windows(?).

Does anybody get Freeview terrestrial digital through the communal aerial/wiring, and if so does it work?
If not, how else are they getting non-satellite digital? NTL/Telewest Cable?

The terrestrial digital signal is weaker than analogue in most cases, so if it's coming down from the roof using the old cable and is ok then the cable is probably in the clear. Could it be the communal aerial has been changed to one that's good for terrestrial digital but bad for analogue?

[Griffin NoName]

I'm guessing the people who have satellite either have their own high quality cable to roof dishes, or the dishes wall mounted outside their windows(?).

There's one wall dish. We are not allowed to have wall dishes so there was a fuss about it. It's hidden behind a huge tree (but works) so I don't see what the fuss is about. I don't know about the rest. I did a questionnaire but like all questionnaires it was limited, mainly because getting any info at all out of anybody is like drawing teeth. I only asked questions I thought people could answer, except for one, which was do you have any equipment that might be intefering with the signal. No one answered that one

Does anybody get Freeview terrestrial digital through the communal aerial/wiring, and if so does it work?

Yes me and yes it does.

And I assume others too. There are only a few who seem to rely on nothing but the analogue any more.

Could it be the communal aerial has been changed to one that's good for terrestrial digital but bad for analogue?

[/quote]

As far as I know it's never been changed ever since the 1970's The only person who would possibly know is The Treasurer and he has never mentioned a new aerial having been erected and I find it hard to believe he wouldn't have mentioned that as we have endless endless conversations about the life history of the building....... and in particular the aerial.

But of course it's not impossible. Even though the constant stream of cowboys have said it's fine. why haven't any of them tried to sell us a new aerial 

[beagle]

Does anybody get Freeview terrestrial digital through the communal aerial/wiring, and if so does it work?

Yes me and yes it does.

And I assume others too. There are only a few who seem to rely on nothing but the analogue any more.

That's weird. The Freeview digital signal is almost always weaker than analogue (and will be till they switch analogue off), so it's odd that it works fine and analogue doesn't.  The only things I can think of are that:

The communal antenna is optimised for digital.

The roof amplifier works better at the digital frequency than the analogue one (I'm not even sure they're at significantly different frequencies).

People's set top boxes/digital TVs have better internal amplifiers, being more modern, than those old analogue sets.

You are getting a low level of interference which the digital error correction is totally removing.


I doubt it's the last one but your digital box probably has a display for signal strength and error rate which you can look at. An error rate above zero but which does not result in the picture ever breaking up suggests the last of the above possibilities.

If there are only a few people left on analogue isn't the obvious solution to switch them to Freeview? Probably only cost around £50 for a set top box each*, which wouldn't buy you much aerial expert consultancy.
You could try a test box first in each flat in case it is just you with lucky cabling/digital signal strength.

---

* Or £150 for a special Beagle-supplied version (the same box with a picture of a dog stuck over the Sony badge).

[Griffin NoName]

....your digital box probably has a display for signal strength and error rate which you can look at. An error rate above zero but which does not result in the picture ever breaking up suggests the last of the above possibilities.

I can check that.

If there are only a few people left on analogue isn't the obvious solution to switch them to Freeview? Probably only cost around £50 for a set top box each*, which wouldn't buy you much aerial expert consultancy.
You could try a test box first in each flat in case it is just you with lucky cabling/digital signal strength.

If only life were that simple. I did say it was an insane need. I cannot describe the depth of resistance. Everyone having to buy a box because the aerial doesn't work? No way, Jose. The aerial ought to work. .... <snip several conversations> well you'll need a digital TV OR a digital box connected to your TV in 2008 ANYWAY <snip ignore statement> <snip repeat statement> < snip they have to sort the aerial out > <snip endless >

I have three digiboxes (and now a DVD tuner too!!) to get round not having a decent analogue signal. But you'd think they were something from Mars.

These are people who haven't yet heard of VCRs let alone DVD.

---

* Or £150 for a special Beagle-supplied version (the same box with a picture of a dog stuck over the Sony badge).

Is that the HMV badge ? that might go down ok 



[/quote]

[beagle]

Oh boy. OK.

Plan A.

Set up a residents' committee with the purpose of looking into the practicality of setting up a commission to investigate the possibility of an enquiry into the feasibility of involving further consultants, with a view to providing a preliminary technical report into the relevant issues, with due regard to environmental and health and safety issues pertaining to staff operating at altitude.

With a suitable definition of what constitutes a quorum that should stall everything until the analogue signal has been turned off and the buggers will have to have what they're given.


Plan B

Push the whiners off the roof.


Plan C

Pay a relative a tenner to come round in a boiler suit with a clipboard and explain patiently that analogue will never work, due to the proximity of the vertical helicons to the gudgeon pins, and the inability to source that particular type of thermostatic non-return valve any more, guv.


Plan D

Explain that the roof amplifier has been damaged due to one of the residents watching large amounts of porn. Not to worry though, the technical experts reckon they'll be able to work out which flat it was with just a few more hours work. Expect a few residents asking for "a quiet word".




Nice picture, but I understand HMV have retired Nipper for a year and Gromit will be standing (sitting?) in for him.

[Griffin NoName]

Thanks. I believe I can run options A,C and D concurrently with Option B as the backup. Option A is a cynch. We are well down that path already and the quorum is 3 - easy.

Last night I got two instances of digital picture loss which hasn't happened for months and months. Mind you, the BBC news has had a spate of this; now we go to our intrepid reporter in ForeignTroublesSpot, what's it like there Jeremy?....... We seem to be having trouble at the moment, we'll come back to Jeremy later.

[beagle]

That sort of nonsense wouldn't have happened with Kate Adie.

It's hard to know which are proper wars and which sabre rattling now she's not sent out to the real ones any more.

[Sibling Chatty]

I really like plan B, bud D has promise in the 'extraneous cash in pocket' field.

[Griffin NoName]

That sort of nonsense wouldn't have happened with Kate Adie.

It's hard to know which are proper wars and which sabre rattling now she's not sent out to the real ones any more.

You can tell she is a no nonsense sort of person from her quote on that link. A woman who calls a lavatory a lavatory !