Give it a boost
In the late 60's when I was a slightly precocious teenage schoolboy interested in electronics, I convinced my father that I could squeeze a bit more life out of our old black and white TV, that was gradually fading away.
Opening it up I located the mains transformer which, like most in those days, had various taps on it to adjust for slightly different AC mains voltages around the country. I moved the the wire to the next tap, which increased the voltage in by about 10 volts. I switched it on and my father marvelled at the increased brightness of the screen. Maximum brownie points.
Three months later there was a bit of a bang and a burning smell.
Oh well, we needed a new one anyway...