TV aerial

[lateron]

Okay I finally succombed to family pressure and for the long, dark, cold evenings we sometimes get on board have installed a small tv/dvd combi. Works fine as DVD/USB but cannot get a digital TV signal.
Anybody out there got any recommendations for an aerial that will at least give me a chance of a signal?
Put aside your objections, any help welcomed!!!
And yes we do also read books, talk and drink red wine!!

Ron [UK]

[Don Reaves]

Many of my boating friends have a mast-mounted TV/FM antenna that looks like a flying saucer. Decent ones aren't cheap, over $100 US. For example, West Marine has one from Shakespeare www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?productId=15959&catalogId=10001&langId=-1&storeId=11151&storeNum=50157&subdeptNum=50187&classNum=50190#.UIu-wGcy3bw

One friend has a similar antenna, but without a case. He keeps it in a locker, rather than having it mounted at the top of the mast. When he wants to use it, he raises it with a halyard. I haven't seen anything like it for sale, but you might find or build one yourself.

Don

[rene460]

No need to apologise, it seems like 75% of boats on our marina have TV and the others are rarely occupied. Happy crew = Happy Skipper!
We have a Majestic UFO TV antenna, one of the more expensive, but works well in our fringe area location. I assume other similar priced units would work just as well, eg Shakespeare which is also available here though I do not know anyone using them. Many cheaper ones available but do not have a good reputation in our area. May be worth a try if you are in a strong signal area, but throw it out if it does not work. Initially I hauled it up on a halliard when in use, stowed it when sailing. Now have permanent mount on top of Bimini. More convenient, but no flexibility to lift it higher on poor signal nights which will become more frequent as the sun flare cycle increases.
Rene460

[Seagem]

We bought our tv/dvd combi from Asda together with a flying saucer type aerial intended to be mounted on a wall or chimney. I put the tv on the chart table of our SO42i and put the aerial through the small hatch above. It works for most of the freeview channels but if we want more I have to position higher, usually on top of the boom, tied on with some thin cord. I stow everything away back in their boxes when we go sailing.
It would be nice to have a permanent arrangement but I do not fancy trying to route the coax cable down the mast and around the cabin to the chart table. Some people mount the tv on the bulkhead between the saloon and forward cabin/heads and although it looks good there, it limits how many people can actually watch it in comfort from the saloon seating.
I think the best option for me would be to mount the aerial on a pole out of the way, port aft, with the cable passing through a deck fitting and along the port side behind the all the internal panels to the chart table. I would mount the tv on an adjustable arm on the saloon heads bulkhead i.e. above the chart table seat backrest.

[lateron]

Thanks for your inputs looks like I will be after a 'flying saucer ' type and I guess I would hoist it up with a suitable burgee line.

I mounted the TV on a pivoting adjustable arm on the bulkhead between the loo and the saloon, that's a really out of the way place on my SO32, it's high enough to not limit seating and 4 people can watch in comfort due to the great seating layout on the boat.

If you tighten the screws on the arm itself, everything stays firm even [so far] in force 7. I installed an extra 12v socket on the shelf which it plugs into.
Tx Ron

[cpetku]

My Flying Saucer is mounted above the radar dish and works fine with an analog TV using one of those old Digital to Analog converter boxes.

[lateron]

Thanks cpetku............didn't know you could get converters for digital back to analogue signals. Will investigate further.
Tx Ron

[cpetku]

Back when they discontinued the Analog service in the US the government had a program to make sure converters were available.

Just search BestBuy or Amazon and you'll find them. However these are unique to the US TV system.

Hopefully they had a similar program on the other side of the pond...

[rxc]

Just an anecdote about antennas. While we were sailing north to Scotland this year, we were able to pick up UK signals from Cherbourg. We have one of those flying-saucer, powered(12v) antennas at the top of our mast.

OTOH, however, as we sat in Dover Marina, we could not pick up any UK signals at all, even though we were also able to pick up French signals from Calais. Evidently, the marina is in a "hole", and cannot see the UK transmitters for the Dover area because of the mountains. In other areas in the UK, sometimes we got good signals, but other times, it was spotty. I don't think it was a connection issue, but where the antennas were aimed - usually at the population on land rather than at us on an anchor in the sea.

[jimairey]

Since digital switchover we get fantastic reception of huge number of channels using an amplified indoor aerial. Otherwise we use our camping satellite system...£40 from Lidl and great! Previously on analogue only 4 weak channels could be viewed. We're in N Ireland.

[Xantia]

You may find this article useful.

www.jeanneauaustralia.com/articles/practical-advice

Sorry, I don't seem to be able to make it a link, you'll have to cut and paste. Digital Tv is much the same worldwide.

If you want to build your own unpowered hoistable antenna, the loop dimensions are 405mm on each side. The 75 ohm cable goes to one loop directly and to the other through two parallel 300 ohm ribbons 230mm long. Look up turnstile antennas, this is a turnstile loop. Find another way to space it if wind is common, the plywood flips around. It works as well as a mushroom type antenna.

[caledonia]

Hi

I've fitted the Glomex 12v 'flying saucer' type antenna at the top of the mast of my Sun Odyssey 36.2 and it has worked well. When you sail to a new area you occasionally have to retune the TV but I've always been able to get a signal.

Glen

[Mistroma]

A lot depends on the area where you sail wrt signal strength. No such thing as a Digital antenna for TV, you just need one that covers the correct range. As you will be mobile that means a "wideband" antenna and I'd bet that virtually everything you look at will be suitable in that respect. The Digital ref. is just marketing hype.

I think previous mention of a digital converter by cpetku was just a reference to what we sometimes used to call a "Digibox" in the UK. You'll only need that with an old analogue TV. You mentioned digital so I assume it's not relevant as it will have a digital tuner built-in.

Circular omni antennae work well for many people but are pretty much zero gain. They benefit from being high up as you don't need to point them in a particular direction and might get a better signal up there.

Directional antennae need to be mounted lower down because you need to point them in the right direction. However, you can get ones with quite high gain and this makes a huge difference.

You can also get some sort of amplifier but that usually won't improve a poor antenna as much as you'd hope. However, OK if reception is marginal even with a decent antenna.

I bought a Vision Plus (probably older version of IMAGE 420 UHF Digital TV Antenna). It is directional, has decent gain and worked well at anchor from Cape Wrath to Land's End last year. Not as tidy as a masthead omni but simple to install, just needs a coax extension cable to get it on deck. I actually installed a permanent point below and ran it to an access cover on the mast. I just plug it in there when needed (not used a lot now in Galicia).

If you do buy a directional antenna then it is worth downloading a PDF with location of transmitters in UK. I might be able to email a copy. I seem to remember that it also gave polarisation for each transmitter (Horiz. or Vert.). You normally have the "bars" (non-techy name) in the antenna lying flat for most transmitters but some smaller ones need them to be up & down. The Vison Plus bracket lets you turn the antenna on its side for these.

I found a link to the current Vision Plus. Manufacturer's web-site used to give tech. info. relating to gain and so on.
www.towsure.com/product/Image_53018_UHF_Caravan_TV_Aerial

[ForGrinsToo]

Given that marine VHF (at least in North America) is kind of in the middle of the TV broadcast band, I am wondering if anyone successfully (define that) uses the masthead VHF antenna for TV. There's a balun problem between 50 ohm VHF and 75 ohm TV, but Shakespeare makes a splitter/switch. Would anyone care to report on experience with such a set-up?

[ForGrinsToo]

Ian Fletcher's article is very informative. Should have read it first. My apologies.

www.jeanneauaustralia.com/article/digital-television-and-boats

[keithk]

Hi there,
You may be interested in my experience with a new 409 over the past year. I had a saucer Arial fitted on the mast head, the signal in the marina area is quite poor but to cut a long story short. The Arial has failed and I am using a reasonable quality indoor type that I plug in when needed. It works much better than the mast type and is not prone to failure. Keep it simple and forget anything located on the mast is my advice.

[Trevor]

Hello Lateron,

This article from Hints and Tips may be of some interest.

www.jeanneau-owners.com/hintsandtips/tvaerial.html

Kind regards and happy TV viewing!

Trevor

[so40gtb]

Apr 15, 2013 13:52:51 GMT ForGrinsToo said:

Given that marine VHF (at least in North America) is kind of in the middle of the TV broadcast band, I am wondering if anyone successfully (define that) uses the masthead VHF antenna for TV. There's a balun problem between 50 ohm VHF and 75 ohm TV, but Shakespeare makes a splitter/switch. Would anyone care to report on experience with such a set-up?

[so40gtb]

My day job is Director, RF Systems Engineering, for 62 TV stations in the USA.

In the US, very few digital TV stations operate in the low-VHF band (54-88 MHz). A small number operate in the high-VHF band (174-216 MHz). The vast majority operate in the UHF band (470-698 MHz). The VHF marine band is really not a factor in TV reception, especially if a dedicated TV receiving antenna is used and that antenna has adequate out-of-band filtering.

Most current-generation TV receivers have 75-Ohm coaxial inputs. They will perform best when the receiving antenna also has a characteristic impedance of 75 Ohms, as does the coaxial cable connecting the two (think RG-59/U and its cousins). Piggybacking off the boat's VHF communications antenna is not a particularly viable means of reception and invites deterioration of emergency VHF communications. The reasons for this are as follows (i) most US stations are on UHF channels, not efficiently received by the too-long marine VHF whip antenna; (ii) Marine VHF polarization is vertical, but the TV transmission standard is horizontal (the more savvy stations use elliptical or circular polarization, including a vertical component, but that is far from universal), causing a 100:1 nominal power loss in reception. {This is not an issue with FM transmission in the US - which is almost always circularly polarized, with the vertical and horizontal components equal - so the FM band couplers that attach to marine-band VHF transceivers will and do work, in most cases.}

The best case for TV reception aboard is use of a horizontally-polarized receiving antenna located at the masthead and optimized for UHF reception with inefficient but useful high-VHF reception capability. That does not guarantee service, as intervening terrain between the station's transmitting antenna and the receiving antenna my preclude successful reception. (For example, receiving LA TV stations when anchored on the west side of Santa Catalina Island or near the Palos Verdes hills.) At urban marinas, compact antennas located within the boat may sometimes work, but it's anyone's guess as to optimal orientation, directionally and horizontal/slant/vertical, due to reflections and depolarization in the urban environment. (In downtown Chicago, my employer's station has found that the most reliable reception of its signal at its studio building's roof is a reflection off another building, not the direct signal from the readily-visible transmitting antenna!)

-Karl

[sailbleu]

No arguing with Karl's explanation.
From what I understand is that the aerial has to be located as high as possible.
Which I recently did. Before it was close to decklevel with rather poor reception , now it's on top of the mast and my expectations have now grown about 15 metres.
Mine is the same saucer as described above , be it with a 12volt amplifier

Regards