You might search in some of the VNA-associated notes from HP and Motorola.
I no longer have specific references, but I remember specifically, both
suppliers addressed the problem with fixture designs. HP (Keysite) still
sells fixtures for the purpose applied to test equipment specific
applications. Cloning those fixtures might be the best approach. When
Motorola came out with their line of bipolar (BJT) RF power transistors,
they documented the test fixtures. A few other Japanese suppliers of
small-signal devices did the same.
Wish my memory of 40 to 50 years ago was better.
Dave - W?LEV
On Tue, Sep 22, 2020 at 8:23 PM Reginald Beardsley via groups.io <pulaskite=
[email protected]> wrote:
I found some discussion over a year ago, but nothing since. Has anyone
done this?
I had trouble finding any information on fixture design. Ultimately I
settled on biasing the candidate transistor with PCB edge SMA-F connectors
on a board and then with the appropriate appendages measuring it with the
nanoVNA and possibly some other VNAs.
I just made up a bunch of bare fixture boards. First up is a 2N3904 in CE
form and no feedback. After that I thought I'd try CB and CC before moving
on to feedback.
I know I'm not the only one interested, but I can't seem to find much
record of prior work.
Have Fun!
Reg
--
*Dave - W?LEV*
*Just Let Darwin Work*
