Hey Everyone,
I'm interested in how a universal remote control works. I can't seam to find any good circuits online

. I'm not interested in the firmware or anything, just learning about the circuit of a standard universal remote (with no learning features, just a USB port or something). My best guess is there are a bunch of tact switches, an integrated circuit, a transistor, a few capacitors, resistances, diodes, an infra-red LED, battery casing and something else I can't work out? A circuit diagram or something would be really nice

.
Thx
Antoine