TV on boats

[TimfromMersea]

After having spent a week (almost!) holed up in Ipswich Haven whilst a gale blew outside, I thought that it would be a good idea to explore the idea of a small TV, both for weather forecasts and also to pass the time.

I found a really light and thin 15 inch flat screen type TV from Currys Digital (Dixons as was) and it was only £140 or so. It had all the connections at the bottom and ventilation slots at the sides and top, so was bulkhead mountable - I thought of using self adhesive Velcro strip, which works well with other things, allows easy removal.and doesn't mean any drilling of holes in the bulkhead.

The TV is only 48 watts load and so I bought a 75 watt inverter from Maplins for £20 or so, intending to go back down the street in Ipswich shopping centre and buy the TV.

BUT - the man from Maplin's said that you would never get a signal from a normal portable TV aerial! So that put me off.

I'd like to revisit the idea. Does anyone have any experience of a TV aerial for a sailing boat? Not permanently fixed, but to be got out of a locker and used when necessary? I thought of one of those white 'saw tooth' ones from the caravan shop, wihch seem to get good reports on the Web, and simply lie it on top of the stackpack and move it until a good picture is received.

Any ideas as to whether this would work would be gratefully received!

 

[catalac08]

whatever type of aerial you have you will need 12v signal booster - also depends very much where you are as to the signal you get - close to transmitter perfect signal with any aerial (with booster) some areas no signal at all. I use a glomex which is the best I have used so far and hope even better when mounted up the mast.
Have used caravan type aerials with fair success. Only way i can get SWMBO afloat is with a regular supply of TV soaps!

 

[LadyInBed]

Maplin Omnimax 12/24V d.c . Omnidirectional UHF TV/FM Aerial
for £79.99 would do a job, but it depends on the quality of the signal in the area. For this, ask locally.

 

[robstracey]

My setup uses laptop and tv card usinga 12 supply. the lapop also serves for mobile intert and chatlotter.

The arial i use is just an old vhf whip at the top of the mast, and i dont seem to need a booster in most areas. unless im quite a way out to sea.

 

[alan17]

I use a Glomex fitted to mast top but for years I used the same aerial hoisted on a halyard in a sail bag. Worked fine.

 

[Searush]

Many LCD tv's are 12v and can be run direct from boat supply to avoid the losses in a converter. Signal depends on aerial, its and your location & transmitter location. Try a 12v amplified freeview aerial - analogue reception is due to be witrhdrawn over th enext few years so HMG can sell off the frequencies (& cut our taxes? /forums/images/graemlins/confused.gif)

 

[Refueler]

There yer go ..... plenty of answers ... I have a Nikkai 8" jobbie that is powered direct from domestic 12V, the antena is the telescopic rod when on home pontoon which appears to work but not fantastic. (Note I'm in Latvia and we have no digital or freeview ! Promised but still waiting ...) So rod antena's do work.
The Tv is ex another boat in UK when it apparently stopped working. Seems they have a strange habit of failing if voltage is not steadyor sufficient, then stop working. Go back later and they work again !
Anyway it was originally fitted to a Glomex amplified antena - owner used to hoist via the flag halyard once tied up. That way he didn't have gear up when not needed. Even with swinging / wash from other boats - it worked ... odd ghosting when boat swung but soon settled.

I plan to make up a antena based on frame + criss-crossed wire ......... yes I'm talking DIY, only because out here the mobile antena are not available - then couple it to booster - that is available !

 

[Cerddinen]

There is an alternative solution that has not been mentioned. Echopilot can supply a splitter that connects to your masthead aerial and separates the VHF signal and the Freeview signal. If the reception is sufficiently good this allows Freeview with no need for an additional external aeriel.

 

[TrueBlue]

Not on a sailing boat -

But, been there, done it.

The Maplin man is basically right. Unless you are in a strong signal area, an indoor jobby is unlikely to work, even more so if you are at sea level (!)

There is no such thing as a special Freeview aerial, any external UHF aerial suitable for your area(s) should work

Omnimax aerials (the Maplin jobby in the post below), are fine but a bit expensive.
But:-
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They are great for hauling up a mast, or whatever, as they are onmidirectional.
However, IME, they do not work if your area has a local tv transmitter (local tv aerials have the sharp bits pointing upwards , rather than horizontal).
Even so being omni - they "see" any signal, and if you're between two or more transmitters they can't sort out the sheep from the goats, so aren't a whole lot of use.
[/list]

The more important thing to do is to get your aerial up as high as reasonably practical, and then point ting in the right direction. Not an easy matter if it's on the end of a line, but a long pole which you can rotate may work.

If you buy an aerial, get a log periodic one like this, principally because they are fairly compact and the sticky-out-bits don't intrude as much as a "normal" unit.

I've spent ages fiddling about with aerials on poles getting wet in the *** rain, that in the end I jacked it in, got myself a s/h pace satellite box and dish from Ebay (cheaper than the Maplin sat kit - otherwise the Maplin kit will do and it's all in one box)
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Dish can sit on the hatch roof - height is not an issue
28.2 deg East is always in the same place, whereas the terrestrial transmitter will be in a different direction depending on where you move to (assume some cruising).
You are not dependent on signal strength, 'cos you're always looking up in the sky.
You already have an inverter, and the Sat decoder doesn't take a lot more power, though if you're going to Maplin, perhaps you could swap your 75W for a 150 - just in case. The inverter only takes as much power as it needs.
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[TimfromMersea]

Re: Not on a sailing boat -

Wow! Some very detailed replies. Thanks, one and all.

I hadn't thought of the satellite idea. That's an interesting one....

Thanks again to everyone taking the trouble to reply. Some things to work one in the winter.

 

[emnick]

Re: Not on a sailing boat -

You could always use BBC IPlayer to view programs via laptop, only internet connection required.

 

[William_H]

Re: Not on a sailing boat -

On the basis of your using the TV when moored. The log periodic antenna would be suitable provided you are prepared to realign the antenna each time the boat moves or turns. You may not need an amplified antenna. Everything depends on the signal stregth /location.
Your problem is no different to the nearby houses so take a cue from them except you will probably be lower in altitude.
It would be quite reasonable to try the VHF com antenna on top of the mast. It may be OK. It will be vertical when you need horizontal the wronf lenght to tune correctly to UHF and the cable may have too much loss but it may still be OK.
The omni directional ones are really poor performance but have the advantage of not requiring alignment and so OK when on the move. Hence they almost always require an amplifier built in.
good luck olewill

 

[Refueler]

Re: Not on a sailing boat -

Trouble with amplifiers - they do not correct a bad signal - only amplify what is received. Poor signal is poor signal no matter how strong !