Do you remember BBS? If you're a fan of retrocomputing, you've probably heard of Bulletin Board Systems (BBS). Before the spread of the internet, these digital networks allowed users to communicate, exchange files, and even play online games. At Varese Retrocomputing [...]
LPTEL is a telephone ring repeater: it turns on a light bulb when the telephone is ringing. It connects to the telephone line, so it is independent of the telephone. Telephone ring repeater, components R1 – resistor 47 ohm 1/4 WC1 – […]
SPTEL is a busy phone line detector, which I designed when I was just over 15 years old: it is an LED that lights up when the phone line is engaged by a telephone in conversation. This my [...]