Energy efficient monitor

[fos]

I am in the process of building an energy efficient TinyCore based computer. I intend for the entire system to run off 12 volts so I can use a deep discharge truck battery as a backup power supply.

I purchased a Mini-ITX Via C7 motherboard. I would have preferred a Pico-ITX motherboard but the cost was over twice as much with very little improved energy efficiency. I am using a Logic Supply PicoPSU which is very efficient. I expect to place the operating system (TC) and files on a USB thumb drive. I may eventually purchase either a conventional hard drive or a flash based hard drive when the price and long term reliability improve. Emphase flash drives are getting pretty good but are still expensive per GB.

The main computer will be very efficient. The Comcast cable modem will use a lot more energy than the computer!

I would like suggestions for an energy efficient monitor, preferably 12 volt. I have seen a few mobile LCD units but they are pretty expensive.

Any ideas or suggestions to improve my super low power system?

Jeff

[curaga]

This link might be of interest, he runs off entirely solar:

http://www.tectonic.co.za/?p=4335


I'm under the impression that a desktop lcd that takes 12V should only need a regulator to avoid spikes from the battery, and then it should just work.

[fos]

That was a great link. Thanks

He mentioned all of the hardware except the monitor.

[vinnie]

my economic 190w viseo (packard bell) consume range of 9-17 w

[andrewphoto_andyp]

The monitor is the biggest drain on power.
Bigger monitor,more power.
Monitor backlight is still 'on' whether working in GUI or CLI.
Most monitors (approx. 96%,) use fluorescent tubes, the monitor inverter board usually converts up to 94V for the tubes.
My "Aspire One" is low-voltage L.E.D. backlight.
I would like a L.E.D. backlight for my mini-itx, but they are expensive.
Recently I configured a webcam security system (recording,) & once it was up & running I turned off the monitor.
I've got a cheap VuSys (£45 new of Ebay,) 14" widescreen, and the AC adaptor converts to 12V monitor input plug (the cheap VuSys has got a high grade Quanta panel inside.)
Replaced my car "starting/cranking" battery with "leisure" battery.
"Leisure" batteries not quite "deep-discharge" but good availabilty, never purchase a "starting" battery again.
I've been exclusively using cf/ide,sata adaptors for years now, just purchased D945GCLF2, boot LILO/GRUB failed so installed extlinux, see www.andrewjchapman.co.uk/extlinux_boot.htm
You can get "Aspire One" and other L.E.D. panels off Ebay, but the panel to motherboard cable availability may be a minefield.
Personally, I use monocrystalline cells to charge batteries, rather than polycrystalline or amorphous.

[andrewphoto_andyp]

I would like a 9" car monitor, last time I checked the price was about 18 months ago.
Today a Eonon 9" 800x480 12V 12W is $104 inc. delivery.

I've got one of those common car laptop 12V 70w adaptors, and I can set 15,16,18,19,20,22,24V
If I charge/use my Aspire One I set the switch to 19V.
It is VERY EASY to destroy equipment, especially when working under pressure, done it, got the t-shirt.
My adaptor is fixed at 19V two pieces of matchstick & tape to be sure, that switch is locked.
I know that the 12V doubles to 24V before it becomes 19V, I wish I knew more about electronics.
Bottom line is that little adaptor whacks my car battery, theory does not equal practice.
From actual practical experiment, the Yuasa NP2.8-12 was totally insufficient,and I look at the 4amp & 7amp and they're definately too heavy.
12V li-ion rechargeable for CCTV is the way to go.

[fos]

I have my little box up and running. I'm using it with TC 2.4.1 and Firefox now. It is incredibly fast!

The motherboard is an Intel Celeron Mini-ITX that I purchased on ebay for $35. I already had a 1 GB stick of memory. The power supply is a PicoPSU from Logic Supply for $33. All you have to provide is 12 volts from a decent power brick.

The case is a very sturdy universal case also from Logic Supply: http://www.logicsupply.com/products/m350

The case is a very heavy duty steel case that provides plenty of passive ventilation. The only cooling necessary is the CPU fan. The system barely gets warm, even after extended use. It provides two hidden USB ports behind the front panel. I have one chip there that I store Tiny Core on. It has a movable cross bracket just inside the top of the case. It has a couple of cut outs that would support two fans or a couple of speakers. There is also a fan location available behind the front panel.
This is really a nice case. A lot better and cheaper than anything I was trying to fabricate.

I still haven't solved my monitor problem. I'm still researching. I'm looking for cheap and energy efficient. I'm currently using a Dell 17" CRT that I purchased on ebay for $35. It is not particularly energy efficient.

It is a work in progress. If I only had more spare time!

Jeff

[Guy]

Anyone interested in making a power supply to run a notebook computer from a 24 volt battery (or two 12 volt batteries), should look at the LM338K regulator.

I am talking about building your own power supply from separate parts.

You could run a 17 volt, or 18 volt, or 19 volt (anything up to 23 volts) notebook from a 24 volt battery.

From memory, i think the power supply only needs the LM338K regulator, two resistors and two capacitors, as well as a heat sink or piece of metal to disperse the heat.

There are circuits diagrams for this on the internet.

The LM338K regulator is used in a number of different types of circuits. You need to find one which gives a constant voltage output.

Each LM338K regulator can have a maximum output of 5 amps. If you use two, you can get 10 amps, 3 - 15 amps, and 4 - 20 amps, etc.

Even if the input voltage changes, the output voltage remains constant. A 24 volt battery may be 26 volts when fully charged and only be 20 volts when fairly flat. The output voltage remains constant.

It can only be used to drop the voltage, not increase it. (Different circuits can be used to increase it.)

Anyone making their own electronic circuits should should have a fairly good understanding of electronics, and do so at their own risk. If you do it wrong and fry your computer, don't blame anyone but yourself.

[andrewphoto_andyp]

Fos,
did you bust the two side clips on the front panel like I did?!
Pity the M350 didn't come with a single piece of paper with a diagram.
I think the M350 is a little too heavy, but ultimately I love it, no competition.

Thanks Guy for the LK338K information.
I think possibly 24V = the most efficient, & obviously 2 x 12V series is easy.

Fos,
What size monitor you desire?
14"? 20"?

[fos]

No, I didn't break the plastic tabs.  I guess I was lucky.

My next box will be with one of the Intel Atom mother boards that has a built in power converter. All you need is 12 volts. It also runs without a cpu fan. The ultimate quiet computer (small and energy efficient).

Jeff