Found it! VALVE, volume 4 number 10, October 1997, page 11. It does not incorporate a shunt regulator - that was a later development. (And be aware that usually we refer to a shunt regulated driver stage, but have done a small number of amps with the whole amp shunt regulated - the nomenclature does not do a good job of distinguishing between them.)
It should be a great project, simple but sophisticated.
There are several small changes I would suggest, based on what we've learned over the last 13 years. This circuit, along with the Bottlehead Afterglow (originally Tucker's design) and the custom-only Excite which IIRC existed in both 45 and 2A3 forms, became the starting points for the Paraglow and eventually the 2A3 Paramount - with numerous changes along the way. So we have a variety of experiences with it.
The most critical thing is the power supply, whose voltage must be tightly controlled. In the original, the voltage at the 45 plate was 400 volts, plus 20 volts for the drop across the plate choke - power supply 420 volts. Different power transformers with the same nominal volts can give wildly different output voltages; I have seen over 500 volts from power transformers with the same 350-0-350v nominal rating. This places the power supply capacitors, the current source, and even the 45 at risk of premature failure. (Also there are some typos - the 1/4 watt bleeders will dissipate 2/3 watt; I would not use anything less than a 2-watt rating!)
If you would like some detailed notes on my thoughts, I'd be happy to write up something - ping me through the forum if interested.
