>> of the 3 x 1N4001 in place of the link to the bases.
>=20
> Reduce output x 3 x Vd ~=3D 1.8V.
> Vout can be V_LM317 - 3 x Vd - Vbe_2N3055 ~~~~=3D 0V min
> if Vee is grounded.
>=20
> If Vee is < ground then cct can go to ground without the diodes
> (maybe).

Ah. I was looking at the wrong end. It wasn't to reduce Vout, it was to
reduce base Vmin ie compensate for the 1.25V min of the LM317. I
think I'd prefer a Vee, as changing base current will change the Vdrop
of the diodes

>>  And the 1N5401 feedback from
>> Vout to supply ?
>=20
> That's a reverse discharge diode for when Vin is removed and you
> may have larghe caps on the output (not shown)

Similar to reverse diode across LM78xx. It would be wise then to
include it. Although the PSU itself doesn't have any large filter caps,
the target circuit might have

> Under low to no load with 34VAC then Vincap can go to 34 x
> sqrt(2)~=3D 48V. R plus zener will clamp this

So you're suggesting the more common arrangement of a series R
to ZD k, ZD a to ground. eg a 24 ohm 5W + 39V 5W zener

46.5 - 39 =3D 7.5, I =3D 0.32A

V =3D I * R, R =3D 7.5 / 0.32 =3D 23.4R
P =3D 0.32 * 0.32 * 24 =3D 2.46W
--=20
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