Powr Supply

I already have a Celestron Power Tank 7amp/hr for my 9.25 ASGT scope. I want to get a new power supply so I can use my dew buster without having to worry about power depleting using it on the power tank. K-Mart has a Rally 8amp/hr power booster for $32.95. With two 12v cigarette lighter inputs. Think this would be ok.

8amp hour is not too much, that is a small battery. I use 7amp hour batteries for running the ServoCat, but that is not nearyly the same draw.
I bought a large 45amp hour battery at Wal-Mart (K-Mart will have the same) with a built in handle for about the same price. Then I got a cigarrette lighter splitter at a Dollar Store and put terminals on it and that will run for a long time.

No its not enough. The Kendrick 9" heater is about
2 Amps. Figure a couple eyepiece / finder heaters
and you are up to say 3 Amps total. Even though the
battery is rated at 7 Amp-Hours, you should plan around
half that (the battery will last alot longer that
way, cold weather, etc.). So that gives you about
3.5 Amp-Hours in the battery, drawing 3 Amps and
you've got about 1 hour of power.

I can also say from experience it is nowhere near
enough, having once tried to run off a 7 AH battery.

Advance Auto Parts usually sells the 18 AH
jump starters for $50 - $60. I'd get one or
more of those. Or do as Floyd says and get a big
battery. Make sure to get the sealed non-spillable
type. The regular old-fashioned car battery type
make a huge ugly mess if they tip over and the
acid spills out (been there, done that).

batterymart-dot-com is a good place for sealed
lead-acid batteries.

This may be enlightening:
http://aajonahfish.com/sinewave_power.htm

dan kowall

I built my own power supply using a 12 volt 75AH marine deep cycle battery, and have never looked back. I had a ton of issues powering my LX200 Classic SCT scope using a cheapish 12volt 7AH battery pack. Thanks to some advice on these boards and a couple of local astrobuddies, this turned out to be the right solution.

I went to Kmart for everything, including the battery mentioned above, a marine battery box to place it in, a power switch and some cigarette lighter jacks. Total cost around $80.00. I figure it lasts around 36 hours between charges, and the scope just loves it!

You can see it here: http://theguvnah.blogspot.com/2006/03/power-supply-is-done.html

Robert,
Check these guys out......

http://www.zbattery.com/

Jay

Here is another source for solar cells and charge controllers.
http://www.icpsolar.com/

However the ICP charge controllers work on systems greater than 1 amp charging. I use two of their older 1200 series panels with their older charge controller for my Aunt's cabin with a 115 ah battery. It has been going for three years and with someone leaving the attic lights on over this past winter!
I used their older 350 ma panel to charge a 5 ah set in my NGT-18 power panel (240 ma max draw with drives and secondary dew zapper) and managed to murder by overcharging! Remember 90% of the lead acid batteries don't die by 'old age', they are murdered!
The effect of it was shown this past winter when the low battery alarm went off a dawn at first then I started losing 1/2 hr per night.
I could not find a solar cell charger that handled less than 1 amp. I then took apart a 2 stage, 1 amp "wall wart" AC charger I got from Mouser Electronics and attached wires for the small solar charger to the two 'spare' lug terminals the thing had and got it to work on the 350 ma solar cell.
My career was in electronic repair, DO NOT attempt taking apart an AC Supply if you don't have the proper formal electricity and electronics (EE) training!

I just wanted to post my recent solution to remote power. I bought a 26 amp hr gel cell and installed it in an old "6-pack cooler". A 4 outlet plug unit and a inline switch were added to make a nice portable unit. I use a 1 amp wall wart to recharge which will also fit inside the case.

Walt

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