battery power to TV

[Dvandersys]

I'm using a 15 inch Coby LCD tv for a laptop-style game console/portable TV thing. The TV has the typical PSU board which turns 110vAC to 12vDC and 5vDC. I plan on using a rechargeable NiCad battery to power the thing when it isn't using a wall outlet. (I also intend to use the TVs PSU to power the "built in" N64 and whatever else I decide to cram into the case, like a radio tuner or something). So, my question is, can I simply solder the leads to my battery connector right to the 12vDC leg of the PSUs transformer, and the 5vDC voltage regulator (from the battery) to the 5vDC leg of the transformer, and expect the PSU to charge the battery while powering the game/TV combo? And incidentaly, can I feed 5 volts to the 3.3v portion of my N64 without killing it? Sorry so many questions, hope they make sense! Thank you.

[hailrazer]

And incidentaly, can I feed 5 volts to the 3.3v portion of my N64 without killing it?

No

[Dvandersys]

And incidentaly, can I feed 5 volts to the 3.3v portion of my N64 without killing it?

No

Ah, bummer. Working with three different voltages... Unless the 5 volt portion of the tv can live off 3.3... Blah, this was supposed to be fun, it's turning out to be a lot like work!

Thanks

[timmeh87]

So, my question is, can I simply solder the leads to my battery connector right to the 12vDC leg of the PSUs transformer, and the 5vDC voltage regulator (from the battery) to the 5vDC leg of the transformer, and expect the PSU to charge the battery while powering the game/TV combo?

Similarly, no. Your 12v battery needs like 14.4v to charge.

Why Ni-Cd? They are the least desirable kind of rechargeable battery for most situations.

Is the power supply actually just a transformer? There's further complications in that case but Im assuming it at least has a rectified and filtered output or something right?

[Dvandersys]

Yes, the power supply has a rectifier and filter and all that stuff (I suppose... I really need to take some photos of the thing instead of trying to describe it). As a matter of fact, it sends power to the main board of the TV and also, through a separate ribbon cable, to a small board which is hooked to the LCD screen itself. It would be sweet if I could just figure a way to feed video to just that board and eliminate all the other TV related stuff, though on the other hand, having a portable system that I can watch TV on would be sort of cool, too. Why Ni-CD? Well, least desirable also means least expensive, and weight isn't that much of an issue, as I'm building the thing into a medium sized briefcase. I guess that makes it less portable and more trans-portable. It's actually a 7.9 volt battery, but I assumed since 7.9 can power the 12 volt portion of a N64 (or so I've read) then it should work for the 12 volt portion of the TV too. I don't need really long battery life... hmm, perhaps I should just explain the purpose of this project. I'm in the Air Force, and I've deployed to Iraq a couple of times now, and the power in the dorms/tents over there can be unreliable. I just wanted to put together a somewhat robust, easily transportable unit I can play games on and watch a little TV on, and keep using even if the power cuts out for a half hour or so. I know I could always just throw a TV tuner and a few emulators on a laptop and call it good, but I like making things. Obviously not an expert in the electronics department, but thanks to the posts and other projects on this forum, I'm learning. Thanks for your input, and if anybody has any idea how to feed battery power into this TV (I'm almost wishing I'd gone with a smaller screen that's already designed to take 12 volts... almost), please help me out! Thanks much,

David