The possibilities are vast-- almost limitless, although as the functions become more complex, it is usually more practical to do the job with a microcontroller. In the early 1980's I worked as a technician at the main TEAC USA plant in Montebello, CA, and fixed approximately 1,000 tape recorders while I was there. The oldest ones generally had relay control, then the next generation used lots of logic ICs. Then came the microcontrollers which reduced the parts count and made it more practical to have nice displays, better control of tape tension, etc.. In our aircraft-communications products, we started out 22 years ago controlling the many features with logic gates, but quickly went to microcontrollers to reduce the parts count and assembly costs, as microntroller development became practical and cost-effective for tiny companies.
