Other than being an electronics tech all my life I really don't know what I'm talking about but would think the charger or it's instructions would state the current requirements of the input supply. Once you know that, here is a good source for power supplies.

http://www.mpja.com/

Here's what I'm using and its on sale:

http://www.hobbypeople.net/gallery/158301.asp

Hi Mike,

1. IMHO: you want to have at least a 20 amp Power supply (PS). Anything less and you will not be able to use the new style batteries that we are using that can be charged at a 5C rate (about 12 min. charge times). BTW: I do not have the guts to charge them that fast, but my ERC friends do with no problems. I charge them at 3C and that's fast enough for me! ;-)

2. I use the four PS shown below:

Here is a link to an excellent power supply:

http://sincityjets.com/store-categories.htm

It is the photo in the Accessories link. It is not listed on their web site but I think they still have some. Contact them by email or phone. They are nice people in "Sin City" (AKA LV), my other home town. ;-)

This PS has two large fans and THREE pair of female banana plugs so you can use THREE chargers at once. Chargers are less expensive than more batteries so this is a big help to us. This PS is 20 Amps, very light weight and works well.

3. I also have a Radio Shack 20 Amp PS. This is a slim, light PS that also works well. I made up a plug adaptor that allows using two chargers at the same time. Here is a link: (it is their 15 amp, call to get the 20 amp)

Link:     http://www.radioshack.com/product/index.jsp?productId=2103960

4. There is an engineer at our ERC flying field that makes a beautiful PS from a large File Server for his friends (I have one). It is perfect for our needs. If you want one please contact me off forum and I will see if I can get him to make another one?

5. For some sick reason I am addicted to buying PS and chargers (4 PS, 9 chargers, and counting ;-). I have found that I really like the "ALL IN ONE" charger from Tower when I just want to charge a 5S battery at 1C. I take this to contests to use in the hotel. It is very quiet, light, and compact. It is a good charger combined with a PS and internal balancer. It is easy to use but still has many features. Link:

http://www3.towerhobbies.com/gibing/Wit0001p?&I=LXVZA8&P=ML

6. The "charger" (link below) looks like it will become my favorite charger. My friend Mark (PS builder and electronic engineer in AS industry) said it was the best for the $, and it looks like it is. So far I really like using it. He makes up a wire harness that allows charging of multiple batteries.  The 2nd link is to their PS. Good company (in Hong Kong, perfect English speaking help :-) And unreal prices.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?id Product=6792        Great Charger

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?id Product=9205        Great PS (you will like it)

I hope this info. helps. ...... It's a shame you had to work this past weekend and missed the fantastic GS contest. Seeing Paul's BEAUTIFUL ECL plane fly was worth the 500 mi trip for me! :-) I was looking forward to seeing you there, but I will come up again and see you at the next bay area contest. :-)

Warm Regards, 

Some software (somewhere) added a space to each of these URL's - not uncommon but can be a little annoying.

(http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?id Product=6792)       

Should be:
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6792

likewise -

(http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?id Product=9205)       

should be
http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9205

Thanks guys. That is a lot of good info. I am confident I could modify a power supply for cheap but as Rudy notes I think I would feel safer charging these critical and pricey batteries with a purpose-made PS as well as charger. I am happy with Hobby King/City; I got my TGY 42-50 and lipos from them, took under a week. (Incidentally their "comments" section gives rave reviews to this motor from RC users.)

Rudy: Sorry I couldn't make GSSC; Sat was my wife's birthday and Sunday my gymnast daughter had a meet, which I always attend. Gym season corresponds with model contest season, unfortunately. I would have loved to see PW's E stunter in action. Judging from the scores in Advanced I would have wound up at the bottom of a very select heap anyhow.