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I'd be more than happy to, only that was a long time ago, and that along wi th many other documents of the time have long since disappeared.
From memory there wasn't much to it. An op-amp driving a power transistor a s an emitter-follower, then a diode to protects against the battery feeding back when the power was off. Control was from a high resistance feedback path fr om the battery terminals (so negligable drain on the battery) and somewhere in that lot was the thermistor and a preset pot.
Current limiting was crude - just a resistor in series with the transistor collector.
Not a lot of help I'm afraid :(
Hmmm, thinking a bit more. The thermistor and preset weren't directly in the feedback but in the potential divider producing the reference voltage.
Actually it's remarkable what you remember once you actually start thinking about things. One resister from the battery + to the inverting pin of the op-amp. Something like 470k I think, and the same from there to the common ground. A resistor from a zenner reference to the non-inverting pin of the op-amp, then resistor - preset - thermistor from there to ground. No idea what the values were, nor what specific thermistor it was