Guide to the Tektronix 360 Indicator System

The Tektronix 360 Indicator is a tiny  3" oscilloscope in a rack-mount configuration. It was developed for production line monitoring applications, but became a darling oscilloscope wherever a modular system was required. Today it is a curiosity and a collectors item, but can also be a useful working tool. In fact, a number of these are still in use and under service contract, making the demand for used parts high.

The system considted of the following components. The power supply unit is the 160 or 160A. Either can operate the components, but the 160A is a well regulated rugged unit that is being snapped up for audio, ham radio and other applications not related to the 360 system. These have a small cooling fan in the top of the case which required periodic service, and may be burned up.

The indicator itself uses the old 3WP2 CRT, whiich it shares with the 310A. It is an oscillocope or, at least, part of an oscilloscope. It has a high voltage supply, a vertical amplifier, a horizontal amplifier, and an unblanking circuit. It doesn't have a timebase. The vertical specs are a DC to 500 kHz bandwidth, and sensitivity from.05 V/div to 50 V/div in 4 steps, with a variable control. The horizontal requires a positive or negative going sawtooth, and a positive gate for unblanking.

The waveforms for the horizontal section are provided by 162 Waveform Generator. This little gem provides a calibrated sawtooth and a pulse gate for unblanking the indicator. It could also be used as a repetition rate generator in a chain of events.

Finally there is the 161 Pulse Generator. This unit provides calibrated rectangular pulse output based on a trigger input. When triggered by the 162 sawtooth, it functions as a delay generator, as it can be adjusted to trigger at any point along the rising ramp of the sawtooth.

All of these units were mounted in frames which could then be mounted in a standard 19" relay rack. The units themselves were fitted with octal plugs, and cables were supplied by Tektronix to "daisy-chain" all of the units together to supply power from the 160A. This allowed an engineer to set up a system with as many pulse generators, waveform generators, and indicators as he needed. When the application changed, he need only rearrange the units to perform a totally different function.

Of course, these were also ideal for schools teaching programs in electronics, allowing students to not only see how the various components of an oscillocsope worked, but to develop their own test applications as well.

Today about the only place to find these units is on eBay, although school and Universisty asset-disposal sales and auctions also turn some up. They are great to play around with, and can even be set up for monitoring production lines, biological phenomenon and so on and so on.