BV to OP V1-1

Vol 1-1 Burkhard Vogel from Stuttgart, Germany commented to Ovidiu Popa's article in Vol 1 "On the Noise performance of Low Noise Input Stages", and to Brad Wood's letter to the same article. Vogel's letter contains a complete MathCad noise analysis and the MathCad worksheet is also available for download from within the letter. The full document including Ovidiu's reply can be found here. This is the MathCad worksheet referred to.