Wikipedia:Reference desk/Archives/Computing/2013 October 4

= October 4 =

Car charger needed
I have a gasoline-powered car I don't drive in winter, stored in the garage. The battery is a problem, though. It apparently has stuff running all the time which drains the battery in a couple weeks. Now, I could disconnect the battery, but that causes it's own problems, with the alarm going off when I reconnect, the clock and other computer stuff all resetting, etc. Or I can be sure to run it once a week to charge it, but that wastes gasoline and is a pain. What I'd really like is a charger I can plug in, say to the cigarette lighter, all winter, which will provide minimal charging, just enough to keep it from going dead. Unfortunately, the chargers I've found are for quick charging, and will cook the battery if left on full-time. So, does the type of charger I want exist ? StuRat (talk) 15:21, 4 October 2013 (UTC)


 * This is called trickle charging or float charging. There exist such chargers, Deltran makes one, but I couldn't give a recommendation for a particular brand. --Mark viking (talk) 15:51, 4 October 2013 (UTC)


 * OK, I will Google "trickle car charger" and hope I don't find one with Dick Trickle's face plastered on it. :-) StuRat (talk) 15:56, 4 October 2013 (UTC)

UPDATE: The ones I found all seem to have too high of a max voltage. I'm looking for something like 12.7 V max, but haven't had any luck finding it. The trickle chargers I've found are for charging overnight, whereas I need one that will charge (or rather counter the natural discharge) over a couple weeks. StuRat (talk) 18:41, 4 October 2013 (UTC)


 * You could just try a regulated 12Vdc power supply (eg a old phone charger or something) and put a 100 ohm resistor and a diode in series (Kathode to the battery +ve terminal). The diode would prevent anything happening until the battery went below 11.3V and prevent a charged battery damaging the chasrger. Below 11.3V a maximum of 113mA would be available into a 0V battery and into, say, an 11V battery you would get 3mA which may be enough to keep everything alive. -- SGBailey (talk) 19:16, 4 October 2013 (UTC)


 * Thanks, but I'd prefer an off-the-shelf solution. How about this:  ?  It's 6 watt solar panel designed specifically for charging car batteries, etc.  I'm thinking at 6 watts there's no way it could fry the battery.  How does that relate to the voltage, and how long would it take to charge a 12-volt car battery at that rate ?  (I'm looking for a couple weeks.) StuRat (talk) 19:26, 4 October 2013 (UTC)


 * Float charger or storage charger are good keywords for what you want. K ati e R  (talk) 19:29, 4 October 2013 (UTC)


 * For some reason, these seem less easy to find in the US than in the UK. Amazon in the UK do these: http://www.amazon.co.uk/tag/battery%20conditioner/products.  That should give you something to look for.  --Phil Holmes (talk) 10:10, 5 October 2013 (UTC)
 * I'm sure you already know this Stu, but letting a car sit for 6 months without firing it up invites some problems. Cars need to be driven, even if it's only a few miles, regularly, to keep things lubricated, batteries charged, etc. Mothballing a car is an extensive process (similar to airplanes). Shadowjams (talk) 20:10, 6 October 2013 (UTC)


 * I just realized you mentioned that the battery drains in a few weeks. It can be expected when storing over winter, but a car should be able to sit a few weeks without the battery going flat. If you have access to a decent current clamp (a bit too expensive for most people to have lying around unfortunately) I would suggest hooking it up and seeing just how much current is flowing when the car is off. Pulling fuses would let you narrow down what is the biggest cause and possibly help you find a fault somewhere. K ati e R  (talk) 17:28, 7 October 2013 (UTC)


 * Oh and don't try starting the car with it attached, especially if it's borrowed. I don't know how much protection they put on the sensor windings and the owner would not be happy with you if you fried it. K ati e R  (talk) 17:30, 7 October 2013 (UTC)

Thanks all. Any comments about the solar charger I linked to above ? StuRat (talk) 21:54, 7 October 2013 (UTC)


 * It looks like it is sold specifically for your sort of situation and it gets good reviews. It says it works indoors or in shade, so if you've got a good window to put it near in your garage I say go for it. It's advertised as all-weather so you could mount it outdoors somewhere where it won't get obscured by snow, but it will probably last longer with the less extreme temperature/humidity cycle in your garage. If you're nervous, then just test the battery with a meter a few times over the first several weeks to make sure it isn't losing charge. K ati e R  (talk) 12:28, 8 October 2013 (UTC)


 * Heh, it looks like the only bad review is from someone who tried using it to charge a battery, not maintain it. K ati e R  (talk) 12:31, 8 October 2013 (UTC)


 * OK, I think I'll order it. And I also wouldn't want to use it outside because it would get dirty, and cleaning the solar panel regularly is almost as much work as starting the car regularly. StuRat (talk) 15:30, 8 October 2013 (UTC)

Windows card dragging program
Does there exist a windows (XP) program that will show 52 cards and allow you to manually drag them around the screen? Ideally with a double click to "turn them over" between face and back?

I haven't found anything with google.

I presumably could do it with 52 paint windows on the desktop, or maybe better with 52 images embedded into an excel worksheet. The latter sounds the most promising, especially if I can make them auto-align to the cell grid. Could VBE do the face/back thing somehow?

Any suggestions for a low effort solution? (An alternative is a pack of cards and bluetak on a wall...)

-- SGBailey (talk) 19:07, 4 October 2013 (UTC)


 * What are you trying to do ? Is this the first step in writing a card game program ? StuRat (talk) 19:28, 4 October 2013 (UTC)


 * Use it as a teaching aid for a bridge course. -- SGBailey (talk) 21:40, 4 October 2013 (UTC)


 * I'm wondering if Microsoft PowerPoint can be set up to do this. Pretty sure it can actually. Not sure about the 'dragging around the window' bit. However 52 sequential cards (or Powerpoint 'slides') and 'backs' would be easy, assuming you know how to use the program? I think a 'master slide' with 52 images linked to 52 'cards' (as you were thinking for Excel) is also possible.


 * Seems you are intending to use this directly for teaching, but as a 'handout' too? Powerpoint would allow you to print it easily in multiple formats, and as an executable file to give to students if wanted. --220  of  Borg 01:13, 5 October 2013 (UTC)


 * List of flashcard software may give some help. (Found by Googling "windows flash card program free" by the way)  --220  of  Borg 08:12, 5 October 2013 (UTC)


 * I think the physical cards stuck to the wall might actually work better, and be less expensive. Consider that if you do a demo on the computer, you either need a projector or to clone the display to get more than a few people to see it clearly.


 * Either way, I suggest over-sized cards with the important bits full sized. So, Q♠ taking up the entire card, versus an artistic picture of a queen taking up most of the card.  This should help people make it out from further away. StuRat (talk) 15:41, 8 October 2013 (UTC)

FWIW, I ended up using Excel with the rows and columns sized to be one card big, so that when I dragged them (live), they were easy to put down on grid too. -- SGBailey (talk) 11:01, 14 October 2013 (UTC)