M20 Blank screen

I got a M20 second hand, read the manual, got an couple of shots,but still have a problem.. notmally whhen i switch it on its ok for the first pic, but not always.. the screen is black , it take black pictures even when i review them its black.. tried differnt marco , modes, its usally after the review stage it returns to black screen

Have I missed something or was I sold a dummie .. otherwise its good enought for P & S. its normall animal pics I take ans the continoius shooting mode is great for this.

Ok I didn't pay a lot but i'm annoyed if I've got a useless peice of parts..

Welcome to the forum but bad news I fear. I'm afraid it probably isn't worth repairing since a factory refurbished Grade A one with full Pentax warranty is only £49 from SRS Microsystems. A repair will almost certainly cost more. It is an excellent camera in macro mode.