The Tektronix PS501 is a 0-20 V, 0.4 A + 5 V, 1 A power supply plug-in for the TM500 system.
The 0-20 V 0.4 A output is floating, the fixed 5 V 1 A output is ground referenced.
The PS501 and PS501-2 have coarse/fine potentiometers for setting the variable output voltage.
The PS501-2 additionally features an analog meter to monitor voltage or current.
The PS501-1 has a 0-10/10-20 V switch and a 10-turn pot with mechanical voltage readout.
All versions have a 0-400 mA current limiting pot and an output switch.
Two special modified versions of the PS501-1 exist:
PS501-1 MOD 730E is a modified version to power the strain gage adapter 015-0169-00 or other transducers. The strain gage adapter was initially powered by the 3A10 differential plug in for the 561 or 564 oscilloscopes. When the production of this oscilloscope series was terminated in 1975, the modified PS501-1 MOD 730E became available in 1977 as a replacement power supply, and was produced until 1985.
PS501-1 MOD 730F is a modified version to provide power for the 015-0108-01 Rotational Function Generator (RFG) and to condition its output signals to be connected to the modified 7B53A MOD FB time base.
The 3A74 MOD 730A vertical amplifier and 2B67 MOD 730A time base were originally used in a 561 or 564 oscilloscope as part of the Tektronix Engine Analyzer System. When the production of this oscilloscope series was terminated, the modified PS501-1 MOD 730F became available as a functional replacement for generating the horizontal signals for the gated X-Y display of the 7B53A MOD FB timebase.