--_003_E7FBC8AB52474251BEC416306ADFBF88ivp1_
Content-Type: text/plain; charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable

Hi all

Recycling again

re the attached

The max in-out differential voltage to the LM317 is 40V so I'd
want to drop a few volts off the supply, at least 5V

2N3055 gain is 20-70 @ 4A, transformer rated at 34V 6.5A

Vee will be a small -ve voltage so the output can go down to 0V

So, if I aimed for a Vout max of 38V (assuming regulator/transistor/
resistor losses will probably not quite reach that), at 6.5A that implies
a worst case base current of about 320mA, which will come from the
LM317/350, and will pass through the zener

Would a 6.8V 5W be a suitable dropper ? At less than full current
draw, it would need a load resistor to 'turn it on' ? Maybe 6.2V is
sailing a bit close to the wind

Would you include sharing resistors on the transistor bases ?

And then the diodes I've seen in some designs. What is the purpose
of the 3 x 1N4001 in place of the link to the bases. Simply a voltage
dropper for that particular design ? And the 1N5401 feedback from
Vout to supply ?

TIA

Joe=

--_003_E7FBC8AB52474251BEC416306ADFBF88ivp1_
Content-Type: image/gif; name="v_control.gif"
Content-Description: v_control.gif
Content-Disposition: attachment; filename="v_control.gif"; size=2353;
	creation-date="Mon, 30 May 2011 19:09:49 GMT";
	modification-date="Mon, 30 May 2011 19:09:49 GMT"
Content-Transfer-Encoding: base64
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--_003_E7FBC8AB52474251BEC416306ADFBF88ivp1_
Content-Type: text/plain; name="ATT00001.txt"
Content-Description: ATT00001.txt
Content-Disposition: attachment; filename="ATT00001.txt"; size=208;
	creation-date="Mon, 30 May 2011 19:09:49 GMT";
	modification-date="Mon, 30 May 2011 19:09:49 GMT"
Content-Transfer-Encoding: base64

LS0gDQpodHRwOi8vd3d3LnBpY2xpc3QuY29tIFBJQy9TWCBGQVEgJiBsaXN0IGFyY2hpdmUNClZp
ZXcvY2hhbmdlIHlvdXIgbWVtYmVyc2hpcCBvcHRpb25zIGF0DQpodHRwOi8vbWFpbG1hbi5taXQu
ZWR1L21haWxtYW4vbGlzdGluZm8vcGljbGlzdA0K

--_003_E7FBC8AB52474251BEC416306ADFBF88ivp1_--
.