543

The Tektronix Type 543 is an all-tube 30MHz scope introduced in 1959. It takes letter-series and 1-series plug-ins. It is similar to a 545, but without the second, delayed timebase. Instead, it has a range of horizontal magnifiers from X2 to X100. It has the same six-stage balanced distributed vertical amplifier (twelve 6DK6 tubes) as the 545.