CRT repair near Portland, OR? Sharp 13VT-L200 vcr combo

Recently I got a Sharp 13VT-L200 tv/vcr combo that was described as working perfectly. After a bit of use I found that it would power off by itself, and I wouldn't be able to turn it on again. Occasionally I can turn it on and it stays on for about 30 minutes and powers off again, and the power button does nothing after that. Any ideas about what could be wrong? Or who I could have look at it in the Portland, OR area? Thanks!