TV aerial

[Oliver]

What TV aerials do people recommend?

 

We'd like a small one which can be taken on and off the roof. I've heard you can get a magnetic one.

 

Suggestions as to makes and suppliers would be gratefully received.

 

Thanks

[DHutch]

We dont have a TV, but from what i know from camper vans, and what ive seen, eather you get the omnimax or one of the "flying saucer" type or just stick with a domestic set-top one and spend 2mins lining it up every time, which is my far the cheapest option (the aerial on my uncals camper was £450)

 

- also, a quick search brings up Air-re-alls??

 

"flying saucer ones"

 

"Omnimax"

 

 

 

daniel

[John K]

Got the flying saucer type aerial, plus signal booster fitted. Unless moored in good reception, area picture has never been good. Went to local caravan shop and bought normal tele aerial plus extentable poles. With just one pole clamped to roof and aerial pointing towards transmitter, the picture is almost perfect. I also have a "Freeview" box that works well to. Cost of aerial, about £20 and the extendable poles were £4-99 each, or came in box of three plus clamp for about £17.

[Guest]

Our last boat used an ordinary cheap tv aerial to good effect. We are mounting an aerial from Argos (8 quid or so) on a piece of galavanised electrical conduit ( b and q warehouse ) on this one. We have made a small bracket with the tunnel light/horn mounted on it and the tv aerial pole behind. It (the aerial) will fold flat to cabin roof by removing one small brass pin.

[Andy Woods]

Two peice aerial kit from Wickes (about a tenner), old landing net pole and clamped to the boat with an old pair of mole grips!

Simple, yet effective.

Andy.

[nb maggie]

Our boat came with a saucer type ariel for TV and radio and it was poor especially for Radio.

 

I replaced it with a std car ariel for radio which is now great. For TV a cheap ariel with rubber suckers with long lead that stuck on the roof and can be moved around proved the best.

[John Orentas]

I don't have a TV. The best radio aerial I have come up with, (I never like drilling holes in the roof).

 

Take the coax cable from the radio and cut it close to a window, from the centre wire only run a length of 1.5 insulated cable neatly around the 4 sides of the timber frame close to the glass stopping short of where it started.

 

I have always intended as an experiment to connect it into a true loop to see if that would be better still. Any suggestions from radio chaps ?

 

Ps it's free too

 

John Squeers

Edited December 16, 2004 by John Orentas

[Martin]

I must have tried half a dozen omni-directional aerials as described above before reverting back to the good old fashioned roof-top type - with and without boosters!

Whatever sort you use will depend on your regular viewing spot - if your aerial needs to be on a six foot pole to see over the hedgerows then that's what you need to use.

[Gary Peacock]

The big problem with TV aerials on boats is that you are low down and the signal is blocked and reflected by the surrounding terrain and buildings.

This is the reason most land based TV aerials are on the roof or in the loft.

For many years different manufacturers have produced so called leisure TV aerials in all sorts of weird and wonderful forms and dared to charge some rather extortionate prices too!

 

In my experience all of which were fairly poor their main failing being they all try to be omni directional. IE they receive signals from any direction.

A conventional element style aerial needs to be pointed toward the transmitter but is designed in such away to maximise any available signal.

 

Amplifiers are fine if the picture is poor due to low signal strenth however if the picture suffers ghosting (which omni directional aerials are prone to) the ghost images are also amplified causing more picture problems.

 

I would buy a high gain conventional aerial and rig up a short mast, it involves a bit of messing around but you will achieve the best picture possible for under £50.00.

Remember the TV aerial needs to be mounted either horizontally or vertically depending on your location. (Keep a look out on nearby roofs to find out which!)

 

Hope that helps a bit.

 

Gary

[nbtafelberg]

I've tried 5 or 6

 

The winner by far was a flying saucer type supplied by the LOCKER http://www.thelocker.co.uk

 

Give Stuart or Julia a ring there, now this thing costs £89.95 but comes with a TV booster and works even on digital. They do have some other options.

 

Say that Paul from Tafelberg sent you, they'll know who I am.

Edited December 16, 2004 by clevett

[Yamanx]

90 quid!

 

Thats more than I paid for the telly.

 

Y

[Justin Smith]

I've tried 5 or 6

 

The winner by far was a flying saucer type supplied by the LOCKER http://www.thelocker.co.uk

 

Give Stuart or Julia a ring there, now this thing costs £89.95 but comes with a TV booster and works even on digital. They do have some other options.

 

Say that Paul from Tafelberg sent you, they'll know who I am.

 

 

I don`t understand how an Omni directional aerial can be a winner in any TV reception stakes.

I tested an omnidirectional aerial back to back against my preferred canal boat aerial (a DM Log Periodic) and it didn`t perform too well , which is what one would expect.

As in so many things in life there`s no such thing as a free lunch, and a directional aerial will pick up far better than an omni diractional aerial. Similarly it will reject unwanted signals far better as well.

The "free lunch" moral also extends to the size of aerial too. Basically, all other things being equal, the bigger the aerial the more gain it will have, i.e. the more signal it will pick up.

It is very important to realise that a low gain aerial cannot be made equivalent to a high gain aerial simply by using an amplifier, for simplicities sake, that`s an inferior type of gain !

[Naughty Cal]

Our flying saucer works quite well. Except in the marina where the signal is blocked out by the bigger boats behind us!!!!!

[chris w]

I totally endorse what Justin is saying. An omni ("flying saucer") will never, repeat never, be better than a directional aerial in signal strength picked up.

 

The downside of a directional aerial is that you have to "direct" it at the transmitter. A directional aerial is, as an analogy, like a telescope; it picks up very strongly in the direction in which it is pointing. An omni is like your eyes, in comparison, wider angle but no where as much detail as the telescope.

 

Chris

[alan_fincher]

I also endorse Chris W and Justin's comments.

 

An omni aerial is a heavy compromise compared to a directional one. They work well only in strong signal areas, and will never work well with a poor signal, however much amplifier you put in there.

 

Two further observations about directional antennas though.

 

Firstly, whilst it's true what Justin says that "size matters" ( ), it's also true that the longer one is, the more accurately it needs to be pointed at it's target, (think of Chris's analogy, as you increase the magnification of the telescope).

 

Also a directional aerial, (one with an array of rods), needs to be mounted in the same plane as the signal is being transmitted. Most major long distance TV transmitter transmit "horizontally polarised", and your aerial needs to match that, i.e. have it's elements horizontal. But if you are in an area better served by a lower powered infill transmitter, these are often vertically polarised. For these your aerial rods need to be vertical.

 

The best thing is to see what houses, (rather than boats), near you have, and to mimic that in terms of direction pointed, and whether vertical or horizontal.

 

I'll not go to far into further complications, but if you want one with best chance of working anywhere, it must be a broadband type, (itself another compromise). One aimed at a particular group of channels, (often called something like 'Group D', or another letter), will work weak on transmitters in that group, but less well on those transmitting at frequencies not a good match to the antenna.

Edited April 3, 2009 by alan_fincher

[Tony Brooks]

The big problem with TV aerials on boats is that you are low down and the signal is blocked and reflected by the surrounding terrain and buildings.

This is the reason most land based TV aerials are on the roof or in the loft.

For many years different manufacturers have produced so called leisure TV aerials in all sorts of weird and wonderful forms and dared to charge some rather extortionate prices too!

 

In my experience all of which were fairly poor their main failing being they all try to be omni directional. IE they receive signals from any direction.

A conventional element style aerial needs to be pointed toward the transmitter but is designed in such away to maximise any available signal.

 

Amplifiers are fine if the picture is poor due to low signal strenth however if the picture suffers ghosting (which omni directional aerials are prone to) the ghost images are also amplified causing more picture problems.

 

I would buy a high gain conventional aerial and rig up a short mast, it involves a bit of messing around but you will achieve the best picture possible for under £50.00.

Remember the TV aerial needs to be mounted either horizontally or vertically depending on your location. (Keep a look out on nearby roofs to find out which!)

 

Hope that helps a bit.

 

Gary

 

 

 

100% agreed, height is the key, and although its not as cheap as an old keep net pole I have hinged a 3 section, extending painting/window cleaning pole from the back of the cratch board. This together with a directional Status caravan aerial gives perfectly acceptable and friends say good results. The aerial is stored flat against the hull side just inside the back door when not in use which is why it is not a normal TV aerial. I have just bought a £15 signal strength meter from Argos which certainly helps alignment when no house aerials are in view.

[Naughty Cal]

Suppose i should add then that our flying saucer is on top of the boat about 12ft up on top of the hoop. Maybe thats why we get better signal than some.

[Gretzky]

We have a flying saucer omni directional thing, its mounted on top of the radar arch, but as Gary said the problem with tv's on boats is that most of the time you are pretty low and the signal is blocked by buildings and hills etc. best bet is to try to get it as high as possible. FM transmissions are roughly line of sight. We get an ok picture in the marina with ours on analogue not so good with digital. 5miles away at Torksey we get a great picture all round, digital and analogue.

[Keeping Up]

Can the flying saucers receive vertically polarised signals?

[chris w]

FM transmissions are roughly line of sight.

Apart from bouncing off buildings etc (ghosting) TV transmissions are absolutely line of sight. They don't bounce off the atmosphere (even FM radio is too high in frequency to do this).

 

The formula for line-of-sight reception distance is (from simple geometry):

 

d = 1.2 √h where d = distance in miles from the transmitter and h = the height of the transmitter in feet

 

So, if the transmitter is 1000 ft tall, then the line-of-sight reception distance is around 40 miles.

 

BTW, this is also a useful formula if you are standing on top of a hill and wondering how far away is the horizon? I live on a hill at 800 feet with amazing views across the countryside. So my horizon is approximately 34 miles away.

 

Chris

 

 

Also a directional aerial, (one with an array of rods), needs to be mounted in the same plane as the signal is being transmitted. Most major long distance TV transmitter transmit "horizontally polarised", and your aerial needs to match that, i.e. have it's elements horizontal. But if you are in an area better served by a lower powered infill transmitter, these are often vertically polarised. For these your aerial rods need to be vertical.

One of the fellow moorers in my marina stopped me one day and told me that he had just bought a new high-gain antenna but the results were terrible. I looked across at it and told him that he needed to rotate it through 90 degrees so that the fins were horizontal not vertical. "But it says in the instructions that it will work either way", he said.

 

"That's true". I said, "but they don't mean that it's YOUR choice. They mean, but don't explain properly, that it will work with either vertically or horizontally polarised TV signals. At this location it's horizontal." He rushed over, turned it through 90 degrees, switched on his TV and hey presto - "pictures at last" (or PAL as it's known over here).

 

Chris

[Justin Smith]

Our flying saucer works quite well. Except in the marina where the signal is blocked out by the bigger boats behind us!!!!!

 

 

The thing is that most people don`t realise what a HUGE range of signal strengths there are in this country.

Some people who live on a hill within a few miles of Emley Moor would probably get a reasonable picture with no aerial at all !

There are probably loads of people out there thinking "He doesn`t know what he`s talking about because I get a decent picture off my Omni aerial".

All that proves is that they`re in a strong signal area, a coat hager (a wire one obviously ! ) would probably work as well..

[Justin Smith]

We have a flying saucer omni directional thing, its mounted on top of the radar arch, but as Gary said the problem with tv's on boats is that most of the time you are pretty low and the signal is blocked by buildings and hills etc. best bet is to try to get it as high as possible. FM transmissions are roughly line of sight. We get an ok picture in the marina with ours on analogue not so good with digital. 5miles away at Torksey we get a great picture all round, digital and analogue.

 

Well you would because :

1) It`s pretty flat round there

2) You`re only about 25 miles away from Belmont, or about 30 miles away from Waltham.

Those sort of distances aren`t that far provided you`ve a clear view towards the transmitter.

I did some tests and with a DM Log Periodic aerial (albeit at 1100ft.....) and got big signals off both TXs despite being 55 miles from Waltham and 65 miles from Belmont ! And don`t forget a 26 element Log is a relatively low gain aerial.

Edited April 3, 2009 by Justin Smith

[Naughty Cal]

Well you would because :

1) It`s pretty flat round there

2) You`re only about 25 miles away from Belmont, or about 30 miles away from Waltham.

Those sort of distances aren`t that far provided you`ve a clear view towards the transmitter.

I did some tests and with a DM Log Periodic aerial (albeit at 1100ft.....) and got big signals off both TXs despite being 55 miles from Waltham and 65 miles from Belmont ! And don`t forget a 26 element Log is a relatively low gain aerial.

 

It also has high flood banks!!!!

[blueprince]

Notice observed in a middlewhich hire boat:-

 

"The magnetic aerial is to be placed on top of the boat, not on top of the television as this will distort the picture."

 

Sure enough, the television was well nigh unwatchable with blue and purple bands. Terrible reception too.

 

No I didn't.

[Justin Smith]

It also has high flood banks!!!!

 

You want to try fitting aerials around Sheffield to find out what hills are all about.

Which, of course, is no coincidence. One of the main reasons that the steel industry developed around Sheffield was the hills, sourcing five rivers, to power the water mills.