The Janus shunt regulator made its first appearance in 2007 in the Tube CAD Journal. In a nutshell, the Janus shunt regulator is a tube-based regulator that uses both feedforward- and feedback-based shunt regulation to reject both the rectifier-induced power-supply noise and the signal-induced power-supply noise from its output. This implementation of the Janus regulator was designed to deliver between +250V to +300V worth of B+ voltage. The Janus regulator is not a DC voltage regulator, as it cannot maintain a fixed B+ voltage; instead, it works to eliminate any AC perturbations on its output voltage. In this way it is similar to a large inductor-filled power supply that bucks quick changes in output voltage, but allows slow DC voltage to vary with the wall voltage variations. In other words, with the Janus regulator, the output voltage will depend on the input voltage and the current drawn through the key series resistor. The Janus PCB also holds a low-voltage regulator circuit for the heaters.
Kit does not include a power transformer. Works with transformers between 400V to 550V center-tapped, with 5V @ 2A and 6.3V or 12.6V windings. Do not expect this realization of the Janus circuit to power a KT88-filled power amplifier; it won't.
The Janus shunt regulator kit includes
High-quality, USA-made, PCB that is 4 by 6 inches, extra thick (0.93"), with 2oz copper traces, with four mounting holes
JJ/Tesla or EH ECC832/12DW7 (Optional)
Sovtek 5Y3GT (Optional)
All the resistors needed
All the capacitors needed (Nichicon, Panasonic, MKP10)
Two ceramic tube sockets
LD1085 Low-Dropout voltage regulator
Heatsink for TO220 device
Four sets of PCB standoffs with O-rings
Two Ultrafast 1A/1000V rectifiers
Four Ultrafast 4A/100V rectifiers
24-Page User Guide