Osbourne 1 problems

I recently accquired an Osbourne 1 computer. I turned it on and it seemed to work, I was able to boot BASIC off of a floppy and I wrote a couple little programs, (print hello world, count to ten, and count forever, stuff like that). The picture on the screen was kinda dark in spots, and while the computer was counting, it flickered to a very dark and barely readable, then it went black all together. I tried turning up the brightness and contrast controls, the only one that makes any change on the screen is the brightness control. I can see the rasters when the brightness is up all the way, but the contrast control has no effect. The computer seems to still work though, I can turn it on, then hit enter and it will boot from the floppy. Previously, when it was working, I noticed the screen flicker when the computer accessed the floppy drive. My guess is that there is something wrong with the power supply. Does anyone have any ideas? I would really like to get my Osbourne working again, it's a really cool little computer. Thanks! Ian Primus ian_primus(a)yahoo.com