long time to power on

My Ecco television is one of the old models and not the lcd screen. It takes long about 4 to 5 minutes to power on, and plays well for a few minutes then starts flickering and eventually shows mixed shaking horizontal lines until it powers off again on its own. A friend who is an electrician told me its possible it has to do with a bad capacitor but my problem is I don't know anything about these things. I was wondering if anyone could assist me in identifying the problem and try to fix this on my own because this TV is really cheap and not worth taking to an electrician.