Hackaday (unofficial) June 19, 2021 6:00pm Vacuum Tube Magic Comes To The 741 #classichacks #radiohacks #741 #opamp #tube #hackaday posted by pod_feeder_v2 Vacuum Tube Magic Comes To The 741 Some of you may remember a recent project that featured on these pages, a 555 timer reproduced using vacuum tubes. Its creator [Usagi Electric] was left at loose ends while waiting for a fresh PCB …