485

The Tektronix Type 485 is a dual-trace portable analog oscilloscope with a maximum bandwidth of 350MHz. The impedance of the inputs can be set to 50 ohms or 1 meg. The scope achieves its maximum bandwidth when the inputs are in 50-ohm mode. The 485 was introduced in 1973 uses a switching power supply and uses custom integrated circuits for most of the gain blocks. Triggering is with tunnel diodes.