LCD TV - Help please!

[Andrew38]

Can anybody give me some technical help please?

I've just bought an LCD flat screen TV for the boat. Chose it specifically because it has a transformer stepping it down from 240 to 12v. Aha I thinks no problem, just make a new cable with no transformer in the way and plug it straight into the boats 12v system.

The problem is that it works but with no great enthusiasm! When I first plugged it in and switched it on to autoscan tune it just switched itself on to standby after a few seconds. I then tried it on mains and it worked OK and completed the autoscan and tuned itself in. I then tried it again on 12v and now it's tuned in, it works OK.

I can't believe that suddenly everything is fine - is it short of power, it shouldn't be the boats a new 42 footer and powers everything else perfectly. Any bright ideas?

 

[oldgit]

How big is the invertor on your boat .Perhaps you are getting a lot less than 240 volts and maybe also not 50 hertz.Due to drawing to much current at start up ?

 

[stuartw]

Would suggest that the mains adapter, in common with many others, is giving out much more than 12 volts. This is due to the fact that the TV has it's own regulator inside, who's minimum requirement is 12V. If you are trying to run it off a stabilised 12V, (ie an instrumentation supply via a DC-DC converter) then I would expect problems. If you can get hold of a voltmeter, try and measure the 12v from the mains adapter while the TV is running, ie on load. Do the same from your boat supply. Direct from your batteries ie around 13V, would give you a better chance. Failing that, put the boat's battery charger ON, which if you ARE running straight of the battery, will give you another volt or two.
good luck
Stuart

 

[Robin]

Some LCD TVs like the Sharp Aquos range specifically say in the small print do not use direct on 12v or the warranty is invalid, even though they have a 12v DC feed, especially odd I thought as I was looking at them at Southampton Boat Show. The dealer later confirmed that you must power them from 220v AC or via an inverter. We later bought a Bush TV also with 12v DC feed (and no small print) and it worked fine on 12v in our berth with the charger on (so 13.8v float voltage) but later found it wasn't so happy at anchor with a full battery, but of course at 12.8v. We have an inverter so now run it on that with no problems.

 

[rickp]

We found that the sharp Aqueos we have runs happily on 12v, but it won't run on anything below 11.8. I had a look inside and it seems there are further regulators, so I was happy enough to strap it direct to the boat 12v supply even though that can be a bit more than 12v.

I suspect the 'must run it from the AC adaptor' claim is a CYA thing coupled with that fact that the marketeers probably can't find anyone with enough knowledge of the insides of the product to answer the question sensibly.

Rick

 

[Andrew38]

Thanks for your experience and advice.

Which inverter type did you buy pure or modified sine-wave? As I'm being told that a modified sine wave inverter might also damage low voltage equipment.

 

[Robin]

We were lucky enough to inherit our inverter with the boat, it is a pure sinewave unit I believe and capable of about 500w. It was fitted by the previous owners for running a laptop, which we also do plus other useful jobs like the TV now (and latest aquisition Freeview Box, yet to try off our berth) and soldering iron, recharging batteries for cameras etc. They aren't that expensive but someone else will know better than me which to buy.

 

[mjf]

That is what I like so much about this forum - prompt useful advice from like minded people!

I wondered about this 12v issue for TV's myself. In the end I opted for a laptop which runs thro a power thingy to get its 15v and have a digital TV box/USB that runs off 12v.

Excellent results - and you can record progs onto the hard drive too!

 

[Jobs_a_ good_ un]

i TRIED FREEVIEW FROM POOLE SATURDAY I COUNDT GET ANY RECEPTION IT SAID NO SIGNAL
TRIED IT IN LYMINGTON NO SIGNAL
ONLY PLACE I COULD GET RECEPTION WAS CHICHESTER

 

[rickp]

Freeview is a bit touch and go in places. I can't get it in Northney unless its close to high tide. May have to think about going to a satellite based system to keep the teenagers (and other big kids) happy...

Rick

 

[Planty]

Rick,

I've found this freeview thing to be all about tyhe type of aerial used. Glomex type is virtually useless everywhere, however one of the indoor "Loop plus telescopic arms including booster" types gives a brilliant reception for freeview all over the place. Only real black hole on Solent seems to be Cowes Yacht Haven behind breakwater, however at home in little corner of OV surrounded by 12' high metal piles at times, super pictures. Got the current one from Maplins, £12.99 I think and place it on the "dash" in front of helm position, at differeing jaunty angles until the "aerial installation" feature on the digibox tells me I've got a decent quality signal on UHF channels 23 & 28. (Gives about 30+ programmes).

Ran, TV, Digibox, Aerial & Bose system off the inverter anchored off at weekend and watched the first Grand Prix for years of any interest with a superb picture and surround sound, excellent!! Paul

 

[Robin]

I set ours up in Poole on Saturday too! We have a cheapo B & Q loft aerial (about £8 I think last year) and normally this works in our berth in Poole with the elements horizontal. The only way we got a signal on Freeview was with the elements vertical (ie 90 degs rotated) and we then received all the BBC channels but no others. That said Poole is not a Freeview area yet according to their website and others in our club all have problems. I am told reception is better away from loads of masts and those of us using 'house' aerials seem to do better on analogue than those with expensive UFO style aerials, I don't know if that is the case with digital. I will be looking out for a better version of our loft aerial if such exists without being cumbersome, but as we can receive analogue in the Solent on no aerial at all I'm hoping it will work OK there.

 

[rickp]

Cheers for that Paul - I guess giving a different aerial a shot has to be cheaper! /forums/images/graemlins/smile.gif

Rick

 

[Nick_H]

I was at the NEC boat show just, and the Sharp stand was advertising some device that allowed their products to run on 12v DC. Alternatively there are LCD tv's designed for boats and caravans which will run happily on 12v battery power, such as the Manhattan

 

[KevB]

Fantastic news. Just bought a free veiw box and my boat's in Chichester. Excellent!!

 

[oldgit]

Wonder if that Glomex is for conventional horizontely polarized TV signals whereas the digital stuff is vertical.The dab stuff transmits on around 220 MHZ and suspect that signal is mainly for mobiles like cars etc.

 

[rwoofer]

Been running my sharp off 12V for some time now. No problems.

 

[Wiggo]

Nah, we use a Glomex and it's fine with the digibox. In fact, the box even says it's for digital TV

 

[Gludy]

I had the same problem and ended up fitting a mains plug.

 

[andyball]

freeview at northney

We get freeview ok at Northney....different boxes are better/worse with low signal strength/bouncing off masts.

On our steel boat a new aerial made all the difference & except at very low tides, it's perfect. Even at low lows, I move the aerial somewhere less convenient (it's on suckers) & then no prob's.