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I built the burglar alarm system for my school, 28 years ago while in 12th grade. All TTL circuitry. That portion of the building was remodeled, so it was tor
by madengr 8y ago
I built the burglar alarm system for my school, 28 years ago while in 12th grade. All TTL circuitry. That portion of the building was remodeled, so it was torn out after a few years, but I’m guessing the replacement cost for a commercial system was over $10k.