I have a Minolta Dynax 300si. I am using it since 10 years beside my all other digital cameras. I love my old camere most ...but since lastfew days i am getting it's display is not coming .... i changed the battery .. but no effect / could you please give me a solution?

Sometimes cameras get "confused" if the battery is allowed to die and is replaced. Remove the batteries and wait 30 minutes for the camera to reset then put the batteries back in. This works on rare occasions and does not cost anything to try.

Hope that helps,
Bax

try to get 2cr5 it works :)

Yes.
You can shop the bay http://cgi.ebay.com/NEW-MINOLTA-DYNAX-MAXXUM-XTsi-BATTERY-DOOR-REPLACEMENT-/320374552315?pt=LH_DefaultDomain_0&hash=item4a97cfb6fb

This is the part you need. Dynax is just the European maketed Minolta. Exactly the same.

contacts of the card reader,card clean asjust the contacts.

Hi If it works on a dynax minolta it shoud work on sony digital cameras

Your Minolta QTsi Maxxum takes a Konika Minolta AF lens. These lenses work on these Konika Minolta DSLR cameras:
DYNAX 5D / Maxxum 5D
DYNAX 7D / Maxxum 7D

problems with the Minolta Dynax 300si Battery

In MOST of the cases it's the new battery itself. Sometimes we do not check the manufacturing date on the battery and it is to old to get exhasted in the shelf itself. Otherwise the camera is faulty.

The Konica-Minolta 5d, and 7d, both discontinued but available used on ebay and other places will work with your AF lenses, as well as all the sony alpha camera bodies. KM sold their camera business to sony, and most of the whole maxuum/alpha/dynax group of engineers went with the sale to Sony. I had a 7000, and an 8000i, and all my lenses are quite happy on the 7D I picked up a few months ago on ebay.

Part 1:
http://ca.konicaminolta.com/support/manuals/film-cameras/film_af_slr/dynax_maxxum_400si/Maxxum400siManual-Part1.pdf

Part 2:
http://ca.konicaminolta.com/support/manuals/film-cameras/film_af_slr/dynax_maxxum_400si/Maxxum400siManual-Part2.pdf