ideas on 12V computer and clean power

CreakyDecks

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I wouldn't think short term drops in supply voltage would cause any problem. The battery will act like a big capacitor. Your laptop doesn't "die" when you pull the supply lead out!
 

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pappaecho

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Having posted two days ago regarding the HP C300 laptop, which uses a 10.5 volt battery, I tested the output of the mains PSU which is 12 volts, and the current spec was 2 amps.

Plugged it via cigar lighter into the laptop and it charged OK and it worked, WiFi included, inside the car. Never though before that a volume HP laptop would work in a car/boat - even found a cigar lighter lead with correct size power plug which fitted the laptop.

Looking at the mains PSU, it look dumb, so assume the charging circuit is within the laptop circuitry, which presumably stops the system overcharging
 

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Sometimes I like to pretend I'm clever

I never say anything really rude on the forums. However now ... sometimes I and others spout off to demonstrate that we we know lots of stuff. Actually I think the OP needs to be told this is a piece of piss, not that there are all sorts of complications - which there aren't.

I have the same feeling about sailing magazines. Articles about how easy it is make no good reading. A lot of duffers like me pootle on incompetently without major disaster. This is supposed to be fun.

I'm going to regret this intemperate remark I'm sure.
 

Conachair

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I'm undecided about going for a dedicated boat PC or just sticking with a laptop - couple of questions...

Does the PC crash ever when you start the engine with a big voltage drop?

Is the power supply quiet enough to not have an impact on recieving weatherfax and general SSb use?

My laptop only draws 1.5a with a (noisy! ) maplin car charger so might just stick with it.

TA
 

contessaman

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I'm undecided about going for a dedicated boat PC or just sticking with a laptop - couple of questions...

Does the PC crash ever when you start the engine with a big voltage drop?

Is the power supply quiet enough to not have an impact on recieving weatherfax and general SSb use?

My laptop only draws 1.5a with a (noisy! ) maplin car charger so might just stick with it.

TA

that (mini itx) board is fanless
the PSU I mentioned is fanless
the hard disk is solid state
Its completely silent. Its actually odd to see windows boot up and load without the rumble of a hard disk or whir of a fan.

heres a photo of the computer I built. Im not telling everyone to go out and do this by the way. laptop is fine. I just enjoyed making it over one winter and took it as a challenge to build the most low power pc I could.

and no it never crashes the OPUS ATX PSU is so stable you can crank your engine from the same batter without a glitch.
 

Conachair

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that (mini itx) board is fanless
the PSU I mentioned is fanless
the hard disk is solid state
Its completely silent. Its actually odd to see windows boot up and load without the rumble of a hard disk or whir of a fan.

heres a photo of the computer I built. Im not telling everyone to go out and do this by the way. laptop is fine. I just enjoyed making it over one winter and took it as a challenge to build the most low power pc I could.

and no it never crashes the OPUS ATX PSU is so stable you can crank your engine from the same batter without a glitch.

Looks nice :D :cool:

Sorry , I wasn't very clear. I was wondering about RF noise from the power supply, to get a good weatherfax I need to turn off the fridge and the laptop power supply, too much radio noise from them.

How much power does yours draw??
 

contessaman

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Looks nice :D :cool:

Sorry , I wasn't very clear. I was wondering about RF noise from the power supply, to get a good weatherfax I need to turn off the fridge and the laptop power supply, too much radio noise from them.

How much power does yours draw??

1.1 amps all in with 12 inch monitor and usb gps all on. with the monitor on stby its down to 0.5 amps of which 150 ma is the usb gps. so 0.35 for a pc running xp and chart plotter software aint bad.

Im desperate to break the 1 amp boundary! there are a few leds here and there that are meaningless as they are inside the case so Im going to unsolder them.

re: your question about interference, I have the nasa serial pc navtex (the old one) and that works fine with the computer on. (the old one has to have the computer on it has no memeory in the receiver).

If you are using a communications receiver with something like hammcom I cant vouch for that but I suspect it would be fine as long as the rx isnt right next to the computer. Im sure the fact that I have the whole lot in a metal case helps too.

My isotherm fridge is harsh too. If I have R4 on longwave it intereferes with that. Cold beer or upto date weather, decisions decisions!!
 

Conachair

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1.1 amps all in with 12 inch monitor and usb gps all on. with the monitor on stby its down to 0.5 amps of which 150 ma is the usb gps. so 0.35 for a pc running xp and chart plotter software aint bad.

Oh, now you're getting me all excited :D

20 quid for a motherboard, how much do you think your whole system cost you? rough guess. It's getting more attractive now. :cool:
 

contessaman

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Oh, now you're getting me all excited :D

20 quid for a motherboard, how much do you think your whole system cost you? rough guess. It's getting more attractive now. :cool:

about a ton but thats picking up bits off ebay. I got that same motherboard out of a wyse winterm pc for a lot less than computer dealers sell just the motherboard.
I was very lucky with the OPUS ATX powersupply, they dont come up used often. again lucky to have that custom cse fabricated for peanuts, and sprayed black for beer money too.

I reckon I could build one getting the parts tomorrow for a couple of hundred. I might build another and see what I can get for it on ebay when I get some time. I've just changed boats so need to fit my system to the 'new' boat. its a deck saloon with inside steering so I hope to have the low power monitor and keyboard at the interior helm. then the brighter monitor in a waterproof enclosure at the outside helm. I will post some pictures when its all done but im so busy with work wont be until the spring. I think I'm going to set the monitor into the dashboard that way if its all built in some blighter is less likely to break in and pinch it!

I can recommend having a go at building your own marine pc. its fun getting the current down as much as you can. you'll learn a lot. and if youre in no rush for the bits you can pick them up for pennies. I also have been making my own LED navigation lights over the winter, to cut my electrical consumption. amazingly low current and really bright but the red one still needs some work. got 'warm white' leds for the stern -looks just like the yellowish incandescant light, really bright, 50 milliamps, got the green one nailed, managed to find green-blue coloured leds - again perfect match for the incandescant colour. 80 milliams. trouble is red leds of same tpye and current consumption look a lot dimmer to the eye. so I think its back to the drawing board and more powerful leds in the red one. if it ends up taking a bit more power and being different inside I dont care as long as it looks right from the outside.

oops i've gone off on a tangent again! anyway, get building! its in the spirit of 'practical' boat ownership. make yourself something better than all the other boats have and most importantly, have fun tinkering!!
 

st599

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about a ton but thats picking up bits off ebay. I got that same motherboard out of a wyse winterm pc for a lot less than computer dealers sell just the motherboard.
I was very lucky with the OPUS ATX powersupply, they dont come up used often. again lucky to have that custom cse fabricated for peanuts, and sprayed black for beer money too.

I reckon I could build one getting the parts tomorrow for a couple of hundred. I might build another and see what I can get for it on ebay when I get some time. I've just changed boats so need to fit my system to the 'new' boat. its a deck saloon with inside steering so I hope to have the low power monitor and keyboard at the interior helm. then the brighter monitor in a waterproof enclosure at the outside helm. I will post some pictures when its all done but im so busy with work wont be until the spring. I think I'm going to set the monitor into the dashboard that way if its all built in some blighter is less likely to break in and pinch it!

I can recommend having a go at building your own marine pc. its fun getting the current down as much as you can. you'll learn a lot. and if youre in no rush for the bits you can pick them up for pennies. I also have been making my own LED navigation lights over the winter, to cut my electrical consumption. amazingly low current and really bright but the red one still needs some work. got 'warm white' leds for the stern -looks just like the yellowish incandescant light, really bright, 50 milliamps, got the green one nailed, managed to find green-blue coloured leds - again perfect match for the incandescant colour. 80 milliams. trouble is red leds of same tpye and current consumption look a lot dimmer to the eye. so I think its back to the drawing board and more powerful leds in the red one. if it ends up taking a bit more power and being different inside I dont care as long as it looks right from the outside.

oops i've gone off on a tangent again! anyway, get building! its in the spirit of 'practical' boat ownership. make yourself something better than all the other boats have and most importantly, have fun tinkering!!


I'm going to have a go when the RaspberryPi is released - single board RISC PC at less than 1/2 an amp + a small screen off ebay and a small laptop hard-disk.

Simon
 

Conachair

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about a ton but thats picking up bits off ebay.

Thanks for posting all this, I'm going to go for it. A few more questions...

Which monitor did you get?

Any particular good website to research all the bits?

I'm playing around with LED's as well, easiest quickie so far was a micro switch from maplins turning on a 9v battery and some LED strip inside the fridge when the lid is lifted. Works a treat. And some high power white for the masthead when I figure out an enclosure.

All good fun :)
 

contessaman

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Thanks for posting all this, I'm going to go for it. A few more questions...

Which monitor did you get?

Any particular good website to research all the bits?

I'm playing around with LED's as well, easiest quickie so far was a micro switch from maplins turning on a 9v battery and some LED strip inside the fridge when the lid is lifted. Works a treat. And some high power white for the masthead when I figure out an enclosure.

All good fun :)

Hi mate,

no particualr website, just my trial and error.

I have 3 monitors. the most economical is branded as a harsper 1210. its made for a till and has 12v input.

http://www.baber.com/monitors/harsper_hl1210a.htm

it looks like it was sold under many different badges, I think this is the same:

http://www.ebay.co.uk/itm/DIGIPOS-1...mputerComponents_Monitors&hash=item415b138da5

this ebay shop have quite a few of these for sale.

they all say 12v xxx amps input but thats just the output rating of the mains brick that powers it. the one I have takes between 0.4 and 0.6 amp depends on brightness.

I have a sanyo one at about 0.71 amps and a non branded (much brighter) one at about 1 to 1.1 amps.

that digipos one will be fine below decks. not bright enough for direct sunlight. I assume you want this at your chart table?

the motherboard as we have discussed. via eden 500 mhz.

get a proper vehichle atx PSU. one thats designed for a range of input voltages. this will power the motherboard and also if you use one of the disk drive power leads you will find it has red, black and yellow wires. across the yellow ones you have stabilised 12v so this can power monitor too. Make sure the PSU can handle the current of the monitor on its 12v rail. (the mother board will take a bit)

I was lucky and persistant enough to get a used keyboard like this off ebay:

http://www.made-in-china.com/showro...-Stainless-Steel-Keyboard-With-Trackball.html

although mine was made in USA and secondhand. it panel mounts, looks good with a teak bezel and the trackball is soooo much beter than a mouse at sea. stainless and waterproof - what more could you want?

finally for the hard disk you could use a laptop hard drive with ide adapter. or use a compact flash card with an adapter (only transcend ones will work as a hard drive - my trial and error). or just buy one of these:

http://www.ebay.co.uk/itm/NEW-FLASH...122?pt=LH_DefaultDomain_3&hash=item43a17c65c2

I dfo think solid state is the way forward on a boat. and is the only way to go if you want really low power consumption.
I found 4 gb enough for xp with tsunamis99 and world charts. alternativly that should handle cm93 charts and open CPN. the latter will show your AIS data if youre into that thing.

finally, most usb gps receivers use a somthing called a PL2303 interface. the long and short of it is that xp or win2k will confuse it for a mouse from time to time and the pointer will jump all over the screen. its an easy fix once you know - google it - you just disable 'ms ballpoint mouse' in the registry.

have fun. remember, its all about the PSU. enough watts but not too much or the queiscent current will wast valuable milliamps!
 

fisherman

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finally, most usb gps receivers use a somthing called a PL2303 interface. the long and short of it is that xp or win2k will confuse it for a mouse from time to time and the pointer will jump all over the screen. its an easy fix once you know - google it - you just disable 'ms ballpoint mouse' in the registry.
QUOTE]

You can avoid this by turning on the GPS after the computer, or rather, after opening the programme you use.
 

contessaman

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finally, most usb gps receivers use a somthing called a PL2303 interface. the long and short of it is that xp or win2k will confuse it for a mouse from time to time and the pointer will jump all over the screen. its an easy fix once you know - google it - you just disable 'ms ballpoint mouse' in the registry.
QUOTE]

You can avoid this by turning on the GPS after the computer, or rather, after opening the programme you use.

yes you can, but his invloves plugging your usb rx in and out evertime you turn computer off and on. If you want to hardwire the whole thing and mount the 'brain' of the computer out of sight (and wet?!) with just the monitor and keyboard on show this will be a nause. you could also cut the 5v supply wire inside the usb cable to the gps and fit an inline switch to ahieve the same effect but again that makes the startup process more hassle and its a quick and easy software fix.

I did wonder what the hell was going on at first though with the cursor jumping all over the place!
 
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