The 160 series was a set of modular "bolt-in" instruments introduced in 1952 and was in production until 1970. It was a precursor to the TM500 series of modular plug-in instruments and was designed to provide timed pulses of adjustable duration and amplitude. The 160 series consisted of separate instrument modules with a common power supply. The 125 would power a single module while the 160/160A would power 6 modules. The 160 series modules consisted of a Type 161 Pulse Generator, Type 162 Waveform Generator, Type 163 Pulse Generator, and a Type 360 Indicator. In addition the Type 122 Preamplifier was often used and the later version had the same form factor as the 160 series.
The 160 series was designed by Dick Ropiequet. This description comes from the "Winning With People: The First 40 Years Of Tektronix" book.
"Initially, Ropiequet worked on medical instruments which Tek was developing for the University of Oregon Medical School. These instruments, which were intended for use in the continuation of the work done by Dr. Tunturi on the nervous system, proved successful enough to warrant going into production. Eventually they appeared as the 122 Low Level Pre-Amplifier, the 160 Power Supply, the 161 Pulse Generator, and the 162 Wave-Form Generator, all of which found numerous research applications."
The modularity enabled many different configurations which led to the 160 series to be used extensively in biological research. The museum has this configuration on display.
This 7 page extract from the Instruction Manual shows some of the configurations that can be setup with the 160 series. Click on the image to view the PDF.
The 360 was designed with a paper phenolic PCB but later changed back to ceramic strips. This two sided 360 PCB used eyelets which proved to not be reliable due to thermal expansion issues.
This is a composite image showing both layers superimposed.