[time-nuts] Low noise power supplies?

[Rex]

On 1/31/2013 12:20 AM, Bruce Griffiths wrote:
> With some care its possible to make the emitter current of the shunt 
> transistor approximately PTAT so that, at least for small signals the 
> temperature dependence of the rejection is reduced significantly.

Sorry, what does PTAT mean? I'm not familiar with that term.

>
> Its also possible to build a feedback style shunt regulator that has 
> considerably higher supply rejection than the Wenzel circuit using an 
> opamp and a shunt transistor together with a small resistance in 
> series with one of the supply leads.
>
> Bruce

The Wenzel article gives three circuit topologies. The third shows an 
opamp feeding a 2N4401 across 0.05 ohm in the power path. Sounds like 
what you are describing. Did you miss that one or are you describing 
something different?