system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why are cable boxes so big, yet more technologically advanced devices such as smart phones can fit in the palm of our hands?
gpt
Cable boxes need to contain the analogue circuitry to deal with whatever else (i.e. cable TV) signals, 90V power (in some cases) may be coming down the line.  (the 90V power is for repeaters and other things that make the trunk lines work; should probably be filtered out at the house drop).  You're talking big analogue circuitry... which you could put into a smaller package, but you'd have to cool it. Bigger package and vents = cheaper.