To be more pedantic I'm pretty sue the 'panels' Balfour refer to are the steel sections of the mast itself which were hoisted by the travelling derrick...
The antenna arrays are separate units. We know the top UHF array section is often hoisted by helicopter and placed on top of the mast... Not sure if that happened at Tac, though.
Hence the finished structure height is 206.1 metres and not the 191 metres Balfour state.
I had a look at Balfour Beaty's website today & they say each Aerial panel on the new mast, weighs about 5 tonns;-)
They must be full of lead!
Years ago I had a visit to Rugby radio station and the stats were mind boggling. Each spigot spacing the aerial wires weighed 2 tons and there were quite a few of them suspended up in the sky. The frequency was 16KHz with 1MW power and was keyed (Morse code). There were no nails used in the hut holding the final tuning coil or they would melt and when powered the lights in Rugby would dim. The standby generator was a marine engine which was started using another large engine. This in turn was started using another engine the size used in cars.
I believe the actual antenna panels are custom built by Radio Frequency Systems, from their PHP product range. The main antennas on the top are the regular PHP panels designed for a four-sided cantilever, while the reserve antenna is an array of PHP12S panels.
The PHP panels weigh 11.5 kg by themselves but RFS quote a weight of 528 kg for a 6-tier array with 4 panels per tier. Tacolneston has two of those, stacked on top of each other.
RFS don't quote a per-panel weight for the PHP12S, they quote 4400 kg for a 12-tier array.
The main antenna consists of 48 panels and the reserve of 144 panels, so I'd have to agree that Balfour Beatty are referring to the construction of the mast itself, not of the antennas mounted on it.
I believe the actual antenna panels are custom built by Radio Frequency Systems, from their PHP product range. The main antennas on the top are the regular PHP panels designed for a four-sided cantilever, while the reserve antenna is an array of PHP12S panels.
The PHP panels weigh 11.5 kg by themselves but RFS quote a weight of 528 kg for a 6-tier array with 4 panels per tier. Tacolneston has two of those, stacked on top of each other.
RFS don't quote a per-panel weight for the PHP12S, they quote 4400 kg for a 12-tier array.
The main antenna consists of 48 panels and the reserve of 144 panels, so I'd have to agree that Balfour Beatty are referring to the construction of the mast itself, not of the antennas mounted on it.
Thanks for the clarification folks - yet it did seem a bit much for the panels to weigh 5 ton's each - the combined weight would push the mast into the ground:) & it would end up a foot tall!
Does anyone know - is there a separate feeder going up the mast for each channel multiplex, or are the signals diplexed in some way?
Thanks for the clarification folks - yet it did seem a bit much for the panels to weigh 5 ton's each - the combined weight would push the mast into the ground:) & it would end up a foot tall!
Does anyone know - is there a separate feeder going up the mast for each channel multiplex, or are the signals diplexed in some way?
It's usual to combine all the muxes at the bottom, and feed the composite package up the feeders to the Tx aerials at the top. There will always be more than one feeder up the mast, for redundancy/standby reasons, the aerial array is normally spilt into two halves, and there's a completely separate standby array that is normally not in active use, but is switched in should the main array suffer a major problem.
It's usual to combine all the muxes at the bottom, and feed the composite package up the feeders to the Tx aerials at the top. There will always be more than one feeder up the mast, for redundancy/standby reasons, the aerial array is normally spilt into two halves, and there's a completely separate standby array that is normally not in active use, but is switched in should the main array suffer a major problem.
Take a look at this video, a recently decommissioned analogue TV transmitter in Sydney, but at 44mins are some VHF combiners for DTT (they have DTT on VHF and UHF down there) Whole video is worth a watch
Thanks for those links boys, very interesting - loved the expression: "RF Plumbing" apt, as they do look like water pipes!
There must be a lot of scrap analogue TV transmitters going spare now, with Digital taking over.
I drive past the mast 3 times a week on my journey to work. I think it is unlikely that the dismantling of the rest of the mast will be met by 31st January as apart from the top part of the mast being removed nothing else has changed for weeks.
I drive past the mast 3 times a week on my journey to work. I think it is unlikely that the dismantling of the rest of the mast will be met by 31st January as apart from the top part of the mast being removed nothing else has changed for weeks.
Quick update the deadline of 31 January was definately missed. Nothing has changed. Bet the local authority is not amused we haven't had any particularly prolonged bad weather so why nothing has happened is a mystery.
Quick update the deadline of 31 January was definately missed. Nothing has changed. Bet the local authority is not amused we haven't had any particularly prolonged bad weather so why nothing has happened is a mystery.
Someone may have applied for a Grade 2 listed building restrictions on it or someone may have found a nesting lesser spotted dodo on the mast preventing the masts removal.:D Though I suspect this is more due to the relatively high winds and rain we have had recently. What appears a low wind on the ground is often a gale 500 ft up the mast.
Quick update the deadline of 31 January was definately missed. Nothing has changed. Bet the local authority is not amused we haven't had any particularly prolonged bad weather so why nothing has happened is a mystery.
Well it's been flipping windy and chucking water down from the skies here... on and off all winter. And I'm not all that far away from the site.
Would YOU volunteer to climb up a slippery 150 metres mast in the wet and cold with a stiff breeze to undo the bolts??? I know I wouldn't!!
Even on a good calm day at the top of a TV mast the whole structure can be felt to be swaying!
I'd guess they are looking to get a minimum of two weeks 'good calm weather' predicted... not what is currently forecast. Although it is not unknown for rigging staff to work aloft in the winter when the weather is right I do not think we've had those sort of conditions in the last few months.
'tis only the Parish Council that is worried about the 'look' of the area anyway methinks
Engineers have been working over the past week or so continuing the dismantling process the mast is now only a little higher than the little digital mast.
I was told a couple of weeks ago that they had a target date of today to complete the dismantling - this being the latest in a fairly long list of targets which have been missed. Well, looking out of the window from my vantage point many miles away, unless they make remarkable progress this afternoon they're going to miss this one as well. However, it looks as if it won't be long before the old mast is completely gone now.
I was told a couple of weeks ago that they had a target date of today to complete the dismantling - this being the latest in a fairly long list of targets which have been missed. Well, looking out of the window from my vantage point many miles away, unless they make remarkable progress this afternoon they're going to miss this one as well. However, it looks as if it won't be long before the old mast is completely gone now.
Well I suppose if it is now being dismantled a few days late will make very little difference. It is in nobodies way and little to gain from urgent removal, sitting as it is in a field. I wonder what they will do with it could sections of it be reused somewhere or will poor old Taccy be melted down for scrap?
They used part of the Emley Moor mast that fell down in 1969 as a race officers tower at Huddersfield Sailing Club
I can confirm that part of the old mast is still standing. I understood that a crane was booked 2 weeks ago to take the last bit down but it hasn't happened.
I can confirm that part of the old mast is still standing. I understood that a crane was booked 2 weeks ago to take the last bit down but it hasn't happened.
Yes, I saw it from the A11 today and it looked like a stump of it remained, it did not look very high in fact shorter than than the small mast that stands there. Had to take a quick look as I was driving at the time. Old Taccy "that gave me a dreadful analogue signal for many years) just does not want to go for good, I hate that damn mast. Now I get a great stable perfect signal with digital. I would not be surprised to spite me they have slapped an ancient monument, SSSI, English Heritage or the National Trust have adopted it or something like that on it so it stands for ever annoying me every time I see it.:D
I'm very sorry to see it come down, but it certainly does seem to be defying attempts to remove it. I believe the original target for completion of the task was December 6th!
I'm very sorry to see it come down, but it certainly does seem to be defying attempts to remove it. I believe the original target for completion of the task was December 6th!
A controlled demolition of the original mast would have been good, like was done at Rugby with the masts there, only more spectacular.:D
Comments
The antenna arrays are separate units. We know the top UHF array section is often hoisted by helicopter and placed on top of the mast... Not sure if that happened at Tac, though.
Hence the finished structure height is 206.1 metres and not the 191 metres Balfour state.
The PHP panels weigh 11.5 kg by themselves but RFS quote a weight of 528 kg for a 6-tier array with 4 panels per tier. Tacolneston has two of those, stacked on top of each other.
RFS don't quote a per-panel weight for the PHP12S, they quote 4400 kg for a 12-tier array.
The main antenna consists of 48 panels and the reserve of 144 panels, so I'd have to agree that Balfour Beatty are referring to the construction of the mast itself, not of the antennas mounted on it.
Does anyone know - is there a separate feeder going up the mast for each channel multiplex, or are the signals diplexed in some way?
It's usual to combine all the muxes at the bottom, and feed the composite package up the feeders to the Tx aerials at the top. There will always be more than one feeder up the mast, for redundancy/standby reasons, the aerial array is normally spilt into two halves, and there's a completely separate standby array that is normally not in active use, but is switched in should the main array suffer a major problem.
Typical combiner from random Google
http://www.sira.mi.it/download.php?doc=/upload/documenti/1/11/117/1176.pdf
Take a look at this video, a recently decommissioned analogue TV transmitter in Sydney, but at 44mins are some VHF combiners for DTT (they have DTT on VHF and UHF down there) Whole video is worth a watch
http://www.youtube.com/watch?v=mR_wJkxKSXU
There must be a lot of scrap analogue TV transmitters going spare now, with Digital taking over.
I will post an update when the situation changes.
Thanks
Someone may have applied for a Grade 2 listed building restrictions on it or someone may have found a nesting lesser spotted dodo on the mast preventing the masts removal.:D Though I suspect this is more due to the relatively high winds and rain we have had recently. What appears a low wind on the ground is often a gale 500 ft up the mast.
Would YOU volunteer to climb up a slippery 150 metres mast in the wet and cold with a stiff breeze to undo the bolts??? I know I wouldn't!!
Even on a good calm day at the top of a TV mast the whole structure can be felt to be swaying!
I'd guess they are looking to get a minimum of two weeks 'good calm weather' predicted... not what is currently forecast. Although it is not unknown for rigging staff to work aloft in the winter when the weather is right I do not think we've had those sort of conditions in the last few months.
'tis only the Parish Council that is worried about the 'look' of the area anyway methinks
Well I suppose if it is now being dismantled a few days late will make very little difference. It is in nobodies way and little to gain from urgent removal, sitting as it is in a field. I wonder what they will do with it could sections of it be reused somewhere or will poor old Taccy be melted down for scrap?
They used part of the Emley Moor mast that fell down in 1969 as a race officers tower at Huddersfield Sailing Club
Linkey — http://tx.mb21.co.uk/gallery/gallerypage.php?txid=336&pageid=89
Perhaps Norwich City Football Club may bolt a few sections together and use it at Carrow Road as a look-out post for a new manager:D
Yes, I saw it from the A11 today and it looked like a stump of it remained, it did not look very high in fact shorter than than the small mast that stands there. Had to take a quick look as I was driving at the time. Old Taccy "that gave me a dreadful analogue signal for many years) just does not want to go for good, I hate that damn mast. Now I get a great stable perfect signal with digital. I would not be surprised to spite me they have slapped an ancient monument, SSSI, English Heritage or the National Trust have adopted it or something like that on it so it stands for ever annoying me every time I see it.:D
A controlled demolition of the original mast would have been good, like was done at Rugby with the masts there, only more spectacular.:D
http://www.youtube.com/watch?v=bx2lhSUuGqU
I can confirm that as of a few days ago the old mast has been completely dismantled.