link | frame, telecom, vertical | Tue Feb 4 18:33:13 EST 2020 link | frame, telecom, theory, vertical, wires | Fri Jan 26 18:34:25 EST 2018 link | bell_system, frame, solder, telecom, vertical, wires | Thu Jan 18 19:24:37 EST 2018 link | bell_system, frame, solder, telecom, vertical, wires | Thu Jan 18 19:19:40 EST 2018