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smzarba
2003-Jun-06, 07:30 AM
Hello All,
I live in a so-called "paradise" about 2 blocks from the ocean. But! I rarely get a chance to use my telescope (partly because of my work schedule but mostly) because it's ALWAYS WET!!!!! ahem... cloudy or foggy.
I MUST get myself away from this moisture and lights!
So, my question; can anyone suggest a decent DC source to fun my scope other than my car's battery?
Thanks and sorry if I missed prior posts on this subject.

Jigsaw
2003-Jun-06, 08:05 AM
It doesn't have to run off your car's battery--go down to Wal-Mart and buy a 12-volt car battery just for your telescope.

Portable power packs.
http://www.scopetronix.com/field.htm

Some plans for DIY 12-volt battery packs. FWIW.
http://members.aol.com/planclos/index/battery.htm
http://ngc1514.com/Celestron/power.htm

Then there's this.
http://www.robertreeves.com/class4.htm

Most in-the-field telescope use involves attaching a scope's drive corrector to a 12-volt car battery. The current draw from most telescope drives is very low, only several hundred milliamperes, but the inconvenience of draping power wires from car to telescope can be bothersome. Battery-powered 12-volt dew removal equipment can add to the wiring clutter.

Today, there are several options which can free a telescope from dependence on a car battery. The most common is a small gel-cell battery under the telescope tripod. Gel-cells are sealed batteries which will not leak acid and they come in various sizes and capacities. A Sears Die Hard wheel chair battery is the most common, providing 33 amp-hours at 12 volts. Gel-cells are also common in computer backup power supplies and can be obtained at electronics stores. The down side of a gel-cell is that it must be slowly and carefully recharged. Automobile battery chargers will charge a gel-cell too quickly and damage it. A slow trickle charger is required.

I have successfully powered my telescope with a home made battery pack using rechargeable 1.3-volt nicad batteries formerly used in my son's remote control toy cars. Ten C or D cell nicads combined will provide 13 volts. A holder can be fashioned by using one-inch PVC pipe for C cells and 1 1/4-inch PVC pipe for D cells. A convenient holder can be made by mounting five batteries in two sticks side-by-side which are epoxied together. Slip-on pipe caps form the ends which are held on with a large rubber band.


You can also look up more info on Google under things like "powering your telescope" and "telescope 12 volt battery".

smzarba
2003-Jun-06, 09:06 AM
Jigsaw,
Thanks! That was quick.
BTW, after years of dreaming, I finally got my scope last year and since I lived about 18 miles inland I didn't have near as much problem with all this water in the atmosphere (just light pollution of course). But I moved about 7 months ago and it's been pretty frustrating. You've been a great help.

russ_watters
2003-Jun-06, 04:39 PM
So, my question; can anyone suggest a decent DC source to fun my scope other than my car's battery? What's wrong with your car battery? A scope uses a tiny amount of power.

I once hooked up a 200w stereo system to a car battery at a drive-in movie. Not a good idea.

darkhunter
2003-Jun-06, 06:11 PM
It doesn't have to run off your car's battery--go down to Wal-Mart and buy a 12-volt car battery just for your telescope.

Portable power packs.
http://www.scopetronix.com/field.htm

Some plans for DIY 12-volt battery packs. FWIW.
http://members.aol.com/planclos/index/battery.htm
http://ngc1514.com/Celestron/power.htm

Then there's this.
http://www.robertreeves.com/class4.htm

Most in-the-field telescope use involves attaching a scope's drive corrector to a 12-volt car battery. The current draw from most telescope drives is very low, only several hundred milliamperes, but the inconvenience of draping power wires from car to telescope can be bothersome. Battery-powered 12-volt dew removal equipment can add to the wiring clutter.

Today, there are several options which can free a telescope from dependence on a car battery. The most common is a small gel-cell battery under the telescope tripod. Gel-cells are sealed batteries which will not leak acid and they come in various sizes and capacities. A Sears Die Hard wheel chair battery is the most common, providing 33 amp-hours at 12 volts. Gel-cells are also common in computer backup power supplies and can be obtained at electronics stores. The down side of a gel-cell is that it must be slowly and carefully recharged. Automobile battery chargers will charge a gel-cell too quickly and damage it. A slow trickle charger is required.

I have successfully powered my telescope with a home made battery pack using rechargeable 1.3-volt nicad batteries formerly used in my son's remote control toy cars. Ten C or D cell nicads combined will provide 13 volts. A holder can be fashioned by using one-inch PVC pipe for C cells and 1 1/4-inch PVC pipe for D cells. A convenient holder can be made by mounting five batteries in two sticks side-by-side which are epoxied together. Slip-on pipe caps form the ends which are held on with a large rubber band.


You can also look up more info on Google under things like "powering your telescope" and "telescope 12 volt battery".

I would recommend the Gel-Cels if you do decide to go that route--they are safer because they have no electrolyte to spill if they are knocked over (unliky due to their weigth and size) or dropped. I maintain equipment that uses them, and they are a lot less hassle than the old wet batteries...

smzarba
2003-Jun-08, 05:15 AM
What's wrong with your car battery? A scope uses a tiny amount of power.

I once hooked up a 200w stereo system to a car battery at a drive-in movie. Not a good idea.

LOL!! But I bet the movie sounded great! (hey, it's not anything I wouldn't have tried a while ago....I was going to say 30, 35 years ago, but I suppose it could have been last week too!)

russ_watters, darkhunter, jigsaw, thanks very much. You guys are great

beskeptical
2003-Jun-08, 08:38 AM
Those batteries on the link look superior, but I just wanted to say I have a marine battery. It's still heavy, but it's about half the size of a car battery. I don't use it for scopes, I have it as a power back up for a few appliances at home. The generator is way too loud and the power goes out on occasion. (It's a trade off for all the wonderful trees we have here.)

Also, I keep it hooked up to a 'trickle' recharger for long periods it's not in use. Also got that from the marine hardware store. It's for boat batteries that sit between uses. It keeps them from losing their charge without burning them out from overcharging.