prev. -- follow up

Stage.3 ::

no differential test yet . . . // now is ↓

 

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Update! : 2018.03.04 -- Stage.4 ::

. . . Some clean-up ↓↓

After frequency pass ↓↓

In the old soviet literature it is said to be a good Op Amp ???
. . . for audio frequency operation ... perhaps ???

TEST ↑↑ TEST ↑↑ TEST

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[Eop]