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<DIV>From: "Kenneth G. Gordon" <kgordon2006@frontier.com><BR><BR>> I am
now toying with the idea of completely reversing the polarity of every
polarity-sensitive <BR>> device in this power supply, and substituting
Silicon NPN transistors with almost identical <BR>> specifications for ALL
the PNP Ge devices.<BR><BR><EM>Don't do this. Replace the transistor with your
best guess (but cheap). If that doesn't work, figure out why and make an
adjustment.</EM><BR><BR>> I have yet to find a decent schematic of a more
modern design for a switchable, variable-<BR>> voltage variable-current
supply with current-limiting, or I would simply use the main power <BR>>
supply as the source and replace everything else with a more up-to-date
circuit.<BR><BR><A
href="http://www.siliconchip.com.au/cms/A_102445/article.html">http://www.siliconchip.com.au/cms/A_102445/article.html</A></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><A
href="http://www.siliconchip.com.au/cms/A_112014/article.html">http://www.siliconchip.com.au/cms/A_112014/article.html</A></DIV>
<DIV><FONT size=2 face=Arial></FONT> </DIV>
<DIV><FONT size=2 face=Arial>Neil</FONT></DIV>
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