A TV probably isn't too hard too build, certainly an easier amateur project than a video mixer or PIP unit. However, it would cost considerably more than buying one - unless you could get most of the parts second hand, or even better completely free!.
hmmm. maybe i will try a tv first. it would be utterly thrilling to see a tv i built myself light up with a live broadcast (or taped). a primative, LED looking tv like the ones i've seen in museums, would be even more thrilling! i'm obviously not prepared to complete the PIP device. it is still what i am working towards, but i would rather a couple gratifying interem projects along the way, in order to learn, than weeks, months...years of failure and tedium with an excessive project.
if i bust up a (working) 20 year old tv can i get many of the parts for a DIY tv?