success will be very limited. Shortest possible leads, good bypassing, and adequate shielding as shown above, are ah essential at these high frequencies*
After getting boLh of these units working, i constructed a two meter preamp utilizing the MPFI02 in a grounded source to grounded gate configuration. (This FFT was used because I ran out of the UC734EJ This ore-amp required very little adjustment to get it working. It also seems to outperform my 417A preamp as far as noise figure vs gain, i say "seems'1 because I don't have the know-how or the necessary equipment at this time to perform noise figure tests.
As 1 have tried to indicate, I am no engineer and these units evolved out of a cut and try approach.
I heartily encourage any one needing a good preamp to try one of these because they are not at ail difficult and require a minimum of parts, i suggest though, that before attempting to build one, the reader should refer to the very excellent article by Frank Jones in the Sept. 73 issue. His article covers the basics behind these pre-amps very thoroughly and takes carc of what I have left out. _K6KTP
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