Is the reception from satellite dishes affected by movement of the (moored) boat ?

[RobinR]

It could be a terrace, and the owners could get together and mount a communal dish. It`s common knowledge that having a canal at the bottom of your garden puts up the value of your house, well not everyone can have a canal at the bottom of their garden, but everyone can have a canal boat mounted on their house !

Alternatively, chop a 25ft section out of the middle of the boat and screw that to the wall.

The latter method would also result in a useful garden shed for the man of the house to retire to when the wife`s talking finally gets too much.

Only joking girls !

 

On the Sky thing, I`d have thought that Sky make their dishes that way for a reason. My question is why is that reason significant for a Sky dish on a house, but not on a boat ?

 

Satellite TV is transmitted to the UK from / by Astra 2A/2B/2D from 28.2 degrees east and from / by Eurobird 1 from 28.5 degrees east. The sizes of dish normally used on narrowboats will easily receive both without realignment. The adjoining satellites are Arabsat 2B at 30.5 degrees east and BADR C/3 and Eurobird 2 at 26 degrees east. The Sky dish has a narrower reception gain / narrower focus in the horizontal plane and thus greater rejection re transmissions from these satellites. This is important because all these satellites can and do use the same frequencies. Astra 1 - we used to get our analogue satellite signals from this satellite - is at 19.2 degrees east and there are now 3 other satellites located between the two Astra satellites above! Boats undergo more movement in the horizontal plane than the vertical plane - i.e. they move more from side to side than they do up and down. An elliptical dish has a greater gain than a circular dish with a diameter equal to the minor axis of an elliptical one. With the major axis in the vertical plane it will be less susceptible to horizontal movements than when the major axis is in the horizontal plane.

 

Signals from Astra 2D are at a higher strength than those from Eurobird 1 and other Astra 2 satellites thus initially set up using a signal from Astra 2D - these include BBC 1 programmes, then realign to Astra 2A or 2B or Eurobird 1.

[Justin Smith]

Satellite TV is transmitted to the UK from / by Astra 2A/2B/2D from 28.2 degrees east and from / by Eurobird 1 from 28.5 degrees east. The sizes of dish normally used on narrowboats will easily receive both without realignment. The adjoining satellites are Arabsat 2B at 30.5 degrees east and BADR C/3 and Eurobird 2 at 26 degrees east. The Sky dish has a narrower reception gain / narrower focus in the horizontal plane and thus greater rejection re transmissions from these satellites. This is important because all these satellites can and do use the same frequencies. Astra 1 - we used to get our analogue satellite signals from this satellite - is at 19.2 degrees east and there are now 3 other satellites located between the two Astra satellites above! Boats undergo more movement in the horizontal plane than the vertical plane - i.e. they move more from side to side than they do up and down. An elliptical dish has a greater gain than a circular dish with a diameter equal to the minor axis of an elliptical one. With the major axis in the vertical plane it will be less susceptible to horizontal movements than when the major axis is in the horizontal plane.

 

Signals from Astra 2D are at a higher strength than those from Eurobird 1 and other Astra 2 satellites thus initially set up using a signal from Astra 2D - these include BBC 1 programmes, then realign to Astra 2A or 2B or Eurobird 1.

 

Surely the possibility of picking up two satellite signals of the same frequency is a bad thing ?

Maybe the idea of mounting a canal boat on your wall (so you can use the touring satellite dish on its roof) is not so wise after all.....

Edited July 31, 2010 by Justin Smith

[Radio-Ga-Ga]

Surely the possibility of picking up two satellite signals of the same frequency is a bad thing ?

Maybe the idea of mounting a canal boat on your wall (so you can use the touring satellite dish on its roof) is not so wise after all.....

It was never a real go'er was it?

 

It's not just touring dishes that come in "taller than wide" mine is a 60X55cm domestic pole mounted dish, and as said is very tolerant of boat rocking.

[Mick and Maggie]

Anyone tried mounting a satellite antenna on a gimbal?

 

Shipboard compasses, stoves and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling. So its possible that a gimbal mount should be able to dampen out any movement.

[Radio-Ga-Ga]

Anyone tried mounting a satellite antenna on a gimbal?

 

Shipboard compasses, stoves and even drink holders typically use gimbals to keep them upright with respect to the horizon despite the ship's pitching and rolling. So its possible that a gimbal mount should be able to dampen out any movement.

 

Best idea yet, but too late, everbody followed earlier advice and bolted boat to house, apart from a few who got confused and sank after bolting house to boat.

[WotEver]

Best idea yet, but too late, everbody followed earlier advice and bolted boat to house, apart from a few who got confused and sank after bolting house to boat.

So are you saying that a boathouse it better than a houseboat?

 

Tony

[Justin Smith]

Best idea yet, but too late, everbody followed earlier advice and bolted boat to house, apart from a few who got confused and sank after bolting house to boat.

 

 

Yes, very funny, I`d have been proud of that answer.......

[Radio-Ga-Ga]

So are you saying that a boathouse it better than a houseboat?

 

Tony

In general I'd go with the housboat, but in this case the boathouse is the safest bet.

[Mick and Maggie]

Best idea yet, but too late, everbody followed earlier advice and bolted boat to house, apart from a few who got confused and sank after bolting house to boat.

 

OK, how about this...

 

Motorised HD Satellite Kit for Digital TV £179.99 Order Code: B07LZ available at Maplins plus free delivery.

 

Mick

[Radio-Ga-Ga]

OK, how about this...

 

Motorised HD Satellite Kit for Digital TV £179.99 Order Code: B07LZ available at Maplins plus free delivery.

 

Mick

I know noting about motorised dishes, but don't these type have to be set for each position, then will return to the pre-sets via reciever, rather than being self seeking? If so not much use on a boat, but only guessing so that could all be rubbish.

 

But you're realy aiming these ideas at the wrong person, as one of the minority on this forum who has no difficulty setting up their dish and has no issue with boat movement causing problems, the only worthwhile upgrade would be a self seeking system, but thats loads of money, and you still need a sat nav to make sure you moor in the right spot. Mind you the way things are going, more channels but less worth watching, maybe going back to radio with a coat hanger aerial would be an upgrade, but you can't even do that with a modern coat hanger!

[WotEver]

... maybe going back to radio with a coat hanger aerial would be an upgrade, but you can't even do that with a modern coat hanger!

You won't even be able to do that with your old tranny soon if OFCOM get their way...

 

Tony

[Radio-Ga-Ga]

You won't even be able to do that with your old tranny soon if OFCOM get their way...

 

Tony

Are they still talking about switching most stations to DAB? Thought they might have given up with the broadcasters in the main not wanting to.

[WotEver]

Are they still talking about switching most stations to DAB? Thought they might have given up with the broadcasters in the main not wanting to.

Yeah, they're still talking about it - the Carter Report still stands. However there's absolutely no way it'll happen by 2015 as he "wished". I personally doubt it'll happen in my lifetime. His criterion was that if digital listening (note that's not only DAB but IP also) had reached 50% penetration then analogue should be switched off. Firstly, with DAB sales flatlining and even dropping in some markets, we'll never reach 50% in the next 5 years. Secondly, even if we did reach this magical 50% share do you think the broadcasters would happily turn off half their listeners? They'd kick and scream like crazy.

 

So yes they're still talking about it, but no I don't believe it'll happen.

 

Tony

[Radio-Ga-Ga]

So yes they're still talking about it, but no I don't believe it'll happen.

 

Tony

A quick google just found this, some good news for a change.

 

By James Lyons 9/07/2010

 

About 120 million radios have been saved after ministers agreed not to turn off FM and medium wave channels while listeners are still tuning in.

 

Read more: http://www.mirror.co.uk/news/technology/20.../#ixzz0wHpCy04C

[Grace and Favour]

A quick google just found this, some good news for a change.

 

By James Lyons 9/07/2010

 

About 120 million radios have been saved after ministers agreed not to turn off FM and medium wave channels while listeners are still tuning in.

 

Read more: http://www.mirror.co.uk/news/technology/20.../#ixzz0wHpCy04C

 

Excellent news - - I dare almost think that common sense has prevailed

[WotEver]

A quick google just found this, some good news for a change.

 

By James Lyons 9/07/2010

 

About 120 million radios have been saved after ministers agreed not to turn off FM and medium wave channels while listeners are still tuning in.

 

Read more: http://www.mirror.co.uk/news/technology/20.../#ixzz0wHpCy04C

You'd believe the ramblings of a newspaper media journalist? They understand half of what they're told, retain half of that, and have an attention span that barely covers a tweet.

 

But on this occasion he's (almost) right There's no 'set' date as I said before, and just because Carter says that 50% should be the trigger doesn't mean it would be (as I said before).

 

Tony

[Radio-Ga-Ga]

You'd believe the ramblings of a newspaper media journalist? They understand half of what they're told, retain half of that, and have an attention span that barely covers a tweet.

 

But on this occasion he's (almost) right There's no 'set' date as I said before, and just because Carter says that 50% should be the trigger doesn't mean it would be (as I said before).

 

Tony

You don't believe what papers print? Obviously not a daily sport reader!

[WotEver]

You don't believe what papers print? Obviously not a daily sport reader!

Oh no, I believe The Sport. It's just media journalists I distrust...

 

Tony

[Radio-Ga-Ga]

Oh no, I believe The Sport. It's just media journalists I distrust...

 

Tony

They couldn't afford implants AND journalists, so decided on whoppers all round.

[Keeping Up]

... Boats undergo more movement in the horizontal plane than the vertical plane - i.e. they move more from side to side than they do up and down. An elliptical dish has a greater gain than a circular dish with a diameter equal to the minor axis of an elliptical one. With the major axis in the vertical plane it will be less susceptible to horizontal movements than when the major axis is in the horizontal plane ...

Not sure this is necessarily true. If the dish is pointing out to the side of the boat, and the boat is fairly well moored, there won't be a lot of side-to-side movement but any rolling of the boat (due to passing traffic or due to a heavy person moving about the boat but don't tell Pingu that I said this) will translate to an up-and-down movement of the dish.

 

Excellent news - - I dare almost think that common sense has prevailed

Oh I do hope so !!!

[Iron-Dutchess]

We have a standard sky dish mounted just above the roof. We have no problem setting it up when we move the boat, and no problem with signal loss due to the small amount of boat movement. But then again ours is 55ft x 12ft and weighs 30 tons. . . The boat that is, not the dish

[Martyn Hicks]

If the satellite dish is lined up correctly,and the lnb is set correctly then movements inside the boat and outside shouldn't make any difference at all to the picture quality.if its on it stays on...what can make a difference and cause the picture to pixulate the boat able to swing about 1/not securely tied up, 2/dish and or the lnb not lined up to the satellite,(the smaller the dish the better the signal in the first place and less likely to loose the signal) and 3/ the obvious one trees and tall buildings knocking all or part of the signal (depends on where you moor)....If you fix the dish to the centre of the boat any movement is less on the dish as opposed to fixing it to one side or the other...

 

MARTYN

Edited November 7, 2010 by Martyn Hicks

[nb Innisfree]

Anyone contemplating bolting a narrowboat to the side of a house would be well advised to use very large washers on the inside of the house wall, preferably as large as possible and make sure they are of sufficient thickness, I would suggest at least 3" thick.

Edited November 7, 2010 by nb Innisfree

[Justin Smith]

If the satellite dish is lined up correctly,and the lnb is set correctly then movements inside the boat and outside shouldn't make any difference at all to the picture quality.if its on it stays on...what can make a difference and cause the picture to pixulate the boat able to swing about 1/not securely tied up, 2/dish and or the lnb not lined up to the satellite,(the smaller the dish the better the signal in the first place and less likely to loose the signal) and 3/ the obvious one trees and tall buildings knocking all or part of the signal (depends on where you moor)....If you fix the dish to the centre of the boat any movement is less on the dish as opposed to fixing it to one side or the other...

 

MARTYN

 

The smaller the dish the easier it is to line up because the acceptance angle is greater, but, conversly, and obviously if you think about it, the amount of signal collected is less, so more prone to weather etc affecting the picture. Omni TV aerials are the same, they don`t need any setting up, but will only work in a strong signal area because their gain is so low, actually negative in fact.

 

We have a standard sky dish mounted just above the roof. We have no problem setting it up when we move the boat, and no problem with signal loss due to the small amount of boat movement. But then again ours is 55ft x 12ft and weighs 30 tons. . . The boat that is, not the dish

 

It works both ways, we have customers buying aerials off us who think that setting up a Sky dish is too much hassle.

The truth of the matter is that there are places where a satellite will give you a perfect picture and an aerial only a poor picture, but equally there are places where an aerial will work and a satellite won`t work at all, e.g. when there`s a building or tree in the way of the satellite.

I think most people agree that an aerial is usually easier to set up, esp if there are houses around so you just point your aerial in the same direction (and the same aerial polarity) as their`s, i.e. you don`t need a meter or anything. You can try the same trick with other boats, but they`re not always aligned onto the best transmitter, so I`d generally go with where the house aerials point !

 

Anyone contemplating bolting a narrowboat to the side of a house would be well advised to use very large washers on the inside of the house wall, preferably as large as possible and make sure they are of sufficient thickness, I would suggest at least 3" thick.

 

And try to avoid mounting a narrowboat on your chimney, unless it`s a particularly large one, the chimney I mean, not the narrow boat.

Edited November 8, 2010 by Justin Smith

[RobinR]

Surprised to see this still going however here are some relevant points I posted elsewhere recently:

 

A smaller dish mounted close to the centre line of the roof will be subjected to the minimum movement. A cheap free to air box - secondhand from e-bay - may make alignment easier espically Comag ones with a tuneing "BEEP" feature. When aligned, the dish can be moved minimally without loss of signal. Set it up for the mid point for both horizintal and vertical movement thus minimising the loss of signal for movement of the boat. A SKY dish is not ideal for use on a boat. A smaller dish with the major axis of the elipse in the vertical plane is far better - I can explain:-

 

 

Visualise the LNB as a light source (bulb) and the dish a full or segment of a reflector with the bulb at the focal point aimed at a vertical flat white sheet some distance away. As dish size increases, the area illuminated decreases and the brightness of the illuminated area increases because the fixed quantity of light is illuminating a smaller area. The receptoion of the satellite signal is this process in reverse. As an example Sky reception in far flung places in europe requires larger dishes as the distance from the UK increases. The larger dish "sees" a smaller area of space but gathers a higher level of signal from it thus needs a greater degree of precision at alignment.

 

For an eleptical dish with the major axis in the horizontal plane, the gain is greater for the desired satellite as is the rejection satellites located in the "slots" either side. Geostationary satellites are located in agreed "slots" across the Clarke Belt thus signals from satellites either side of Astra 2 could potentially cause interference hence Sky opted for a dish with the major axis in the horizontal plane reducing the potential for such interference. The smaller dishes with the major axis in the vertical plane can tolerate greater horizontal movement as happens when a moored boat moves due to occupants moving in the boat or passing boats causing movement to the moored boat. Whilst these dishas have less gain, modern LNBs have higher gain thus accomodating this loss at least for the areas where navigable canals are found in England and Wales.

 

 

and

 

I purchased a Comag Portable HD System which is easy to set up, has HDMI. RGB Scart and Component Video outputs. It will also record to a USB memory stick or expansion drive! Best to set up a personalised favourites list then very easy to use and set up. It comes with a 240vac to 12vdc adaptor and a car cigarette lighter plug thus should be more resistant to the higher voltages found in cars / boats / mobile homes etc, because it is designed to be used in a caravan or mobile home.

 

The low noise figure of the LNB with this kit ensures sufficient signal into the receiver from the smaller dish and is sufficient for the UK canal network.