Sorenson 2000S AC Regulator

My uncle gave me this July 2005. It's an AC line regulator designed to regulate 115vac out for an input range of 95-130vac. The output regulation is supposed to be adjustable from 110-120vac. I had envisioned setting it to regulate 110vac for the old Boatanchors. However, I discovered that it really doesn't like to regulate at the bottom end of it's range. It regulates very well at 115vac. Model number is 2000S, the 2000 being the load range in VA of this unit. It regulates the AC line using a saturable core reactor driven by a 6L6. It's works very well, though it is very inefficient. It draws about 5 amps with no load.
As I compulsively do I stripped it down to a bare chassis and rebuilt it. Here's all the parts remounted and ready to wire. Here's a top side view. The huge transformer on the left side is the saturable core reactor. There are  total of 8 transformers in this unit. It's very heavy.
Here's some top and front views (minus the front panel). The meter reads regulated voltage out. I did later add an AC current meter to the left of the voltmeter. Bottom view of the unit with wiring complete.
He's some views of the underside showing the control circuit components. It did initially have a drift problem over a long period of time. After about 4 hours of running it would drift to a point of triggering the circuit breaker. I solved the problem by adding filter capacitance to the screen of the 6L6 which in my opinion had a huge amount of ripple on it. I also adjusted the value of a resistor in the feedback circuit which allowed the feedback to have a greater effect on the regulation. Has run like a champ since. Here's where I have it installed. My plan is to make the regulator the load center for all my radios. Top row of meters are: input voltage, input current, line frequency, 110vac output current, and 110vac output voltage. Meters on the front of the regulator are output current and output voltage from the regulator. Note the big autotransformer in the back.
Here's a back view of the cabinet installation. The knob is connected to the autotransformer. I ended up using the autotransformer to bring the reg 115 down to 110 for the Boatanchors. Sockets on the back are reg 115 and reg 110 out. Here's a closer view of the regulator in the cabinet.


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