I am buying a boat in a few days and know nothing about power supply. I would like to buy a small television for the boat. I am deciding between 9" and 13". In terms of drain on electrical systems, does it make a real difference?
I should''nt think so, but then i wll depend on the boat, the power source 12V vs 120VAC.
How much time you watch it will also come into play.
We liveaboard and currently while at dock the TV is on 120VAC, if we anchor out I change the cord to the 12V cord. But it isn''t necessary to buy a dual voltage TV....you can buy a 13" 120VAC TV at Wal-Mart for about $85.00 and pick up a 300 Watt inverter that plugs into a cigarette lighter and you will be on your way. You may also want to buy a mast mounted antenna...and that may cost you more than the TV!!
Ethan, you''ll find the 13" TV draws more power than the 9" for the simple reason it must fire a much larger tube. The more pressing issues, however, tend to be where a 13" set can live without leaving the dock being a problem or intruding on useable space. Also, you''ll find 12V/110V 9" TVs fairly common - some with built-in VCR, which save some space but will lack features - while I''m not sure you''ll find any 13" units that will operate on 12V. This may be a factor if you aren''t equipped with an inverter aboard. And note the wattage rating on the TV & multiply by 1.2 to get the inverter rating: 10% efficiency losses & 10% so you''re not running the inverter flat out for long periods.
If you go to Radio Shack, some Wal-Mart Supercenters, Pilot Truckstops, Petro Truckstops, T/A Truckstops, Williams Truckstops, Buckhorn Truckstops, and some others you will find plenty of 13" TV''s that run on 12V. You can also find 13" DC TV''s with VCR''s in them. But you will pay a premium for the 12VDC units.
The reason I mentioned the 13" AC with the inverter is for cost savings. I have both 13" TV''s that are 12VDC/120VAC with different cords, and a 13" 120VAC. The 12V unit costs significantly more, better than double $$. It was less expensive to purhase a 300W inverter for $49.00 and the $85.00 TV.
I doubt that the power draw of a 13" tube vs a 9" tube, given all the solid state components is all that different. I think I would put it in the category of negligible. And if your charging system is up to par... there is really nothing to worry about.