https://sites.google.com/a/ricomputermuseum.org/home/Home/equipment/dec-pdp… We removed the 709 power supply and checked for physical damage. Everything looked OK. We reformed all of the capacitors in the power supply. All worked OK. We attached a resistive load to the power supply and measured the output voltages. All looked OK. The power supply fan was sticky so we sprayed some WD40 in the end bearing to free it up. It is noisy, but it works OK a few seconds after it is powered on. We reinstalled the power supply and connected the AC wires. We connected 110VAC to the power cord to the 841A power controller. We could control the power state with the power switch on the console. We connected the remaining red/white wires to the 709 power supply and found that all of the chassis fans work OK. Some are noisy though. The hour meter runs and we add a few tenths of an hour to the 40,163 hours already on the system. We connected the DC wires to the 709 power supply. We turned the power supply on for a few seconds at a time and measured the voltages on the chassis test points. The voltages looked OK and some lights on the console turned on. We tried the basic Examine/Deposit functions, but did not get the expected response. We can turn the PRGM STOP light on and off with the I/O RESET and START switches. With the REGISTER DISPLAY switch in the API position the REGISTER lights flicker. The rate of the flicker can be controlled with the REPEAT SPEED switch. Later this week we will do some basic debugging to see if any of the processor is working as expected. -- Michael Thompson