3A2

The Tektronix Type 3A2 is a dual-trace amplifier plug-in introduced in 1963 for 560-series oscilloscopes. It was designed for compatibility with the digital unit in the 567. Bandwidth is 500 KHz. The input impedance is 47pF. Deflection factor ranges from 10mV/div to 25V/div. The input signal passes through compensated attenuators and then into a 12AT7 cathode-follower stage. Channel switching in ALTERNATE mode is done using diodes. The output stage that drives the vertical deflection plates of the scope uses a pair of 6BA8 pentodes.