At 13.06 2011.12.05, you wrote:
>> An emitter follower will always introduce a Vbe drop, and it will spoil
>> the regulation.  A much better solution is to use a PNP transistor as
>> described in many of the 3 terminal regulator application notes e.g.
>>
>> http://www.onsemi.com/pub_link/Collateral/MC7800-D.PDF
>
>What he says.
>Note also that the LM317 is more flexible in this role due to it's
>lower minimum Vout and the LM317 datasheets often contain sample
>circuit.

Thank You both for the precious insights.

Cheers,
Mario

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