As promised, I made some rigorous measurements of my home brew fixture for
making transmission measurements of various HF circuit elements using a
"professional" instrument. I could have used the NANOVNAs, but using HP
might add some credence to the results ????? Subjects for the fixture
might include common mode chokes, ugly baluns (which I do not use), current
baluns (which I use wound of RG-400 on toroids), filters, and other active
and passive circuits where a fixture is required.
I took the time to calibrate my HP8753C using HP standards with a full
2-port cal from 1 to 30 MHz to make these measurements of the fixture.
Please have a read of the attachment for the results. While the fixture is
essentially free for a few inexpensive components and my time (retired, so
that's free, too). While it's not up to the old HP standards, not bad for
a home baked project which will lead to other projects.
Oh, yes,..... any typos are also free.
If you attempt duplication based on the images, YMMV. Dimensions can be
scoped from the standard alligator clips which are 1.3-inches tip-to-tip (¡À
amateur measurement relying on a non-RF ruler).
Measure everything. Let the data speak for itself, *not *opinion, snake
oil, or sorcery.
Dave - W?LEV
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Dave - W?LEV
