I finally got a second car to keep miles low on my 911. It just wasn't cutting it as a station wagon, so I bought a Subaru to lug my toys around town. I will want to take out the 911 on weekends but may drive it only once every 1 - 2 weeks. Do I need to put the battery on low voltage during this time? Are there other moves necessary to protect it? Thanks in advance.

Use a battery tender (CTEK manufactures the OEM Porsche one)
Full tank of gas + stabilizer
Make sure tires are fully inflated
Put a cover on it and let her go to sleep

However for your case, if you're still planning on driving it every week, I'd just use a battery tender while it's not being used.

thank you. quick, stupid question: I have an Exide 12v charger with a rocker switch offering 6 vs 2 amps. Which is the right setting?

BTW, cool avatar on your profile!

What Subaru did u get? I am also thinking of a 2nd car.

just the basic Outback, 2005 model. I love it! its nice not having to worry about bottoming out everytime i leave a parking lot. It now lugs my scuba gear and kids. Dont go earlier than 2005 unless you want a car with a cassette player and possible head gasket problems.

will do similar soon if the car doesn't sell, may i ask if the cover is only to keep the paint clean? Or is there another reason?

we seem to have gotten off the subject a bit. My last question was...

a quick, stupid question: I have an Exide 12v charger with a rocker switch offering 6 vs 2 amps. Which is the right setting? And do users agree this is necessary if I drive it once per week?

I beleive that the 2 amp is a slower more trickle charge to you battery, the 6 setting will charge quicker.

The most you need to do is add a trickle charger when not in use. Fill the tank if need be. Thats it.

If you drive it once a week then you should not need a trickle charger. The car goes into sleep mode if not used.

I put my car away during the Winter for four months with -25c temps. No gas additive.

The only reason I use a cover is to keep the dust build up off the car and protect it from any accidental dings or scratches. Also the car cover (I use a Dust top) covers the exhaust so it keeps any critters out.