Crystal characterization and
page is a place to put my notes and a few documents from a presentation
I gave at the OzarkCon QRP convention in Joplin, Missouri in 2008.
My slide show was really too big (over 4 MB) in native
PowerPoint, but I converted it into a PDF and made it much smaller.
Same for a Word document that covered the same stuff in greater
It feels incomplete, but you should have seen me trying
to cover all this ground in 50 minutes. I think the crystal
measurements topic is covered pretty well, but the filter design part
is mainly a discussion and overview of available software design tools.
The following links are to my presentation's slide show and an
accompanying text document.
Slide show PDF
was lucky to find (or be found by) Darell Brehm, WA3OPY of
International Crystals (ICM), who introduced me to Bill Carver W7AAZ,
noted ham technical guru and author of a number of articles.
Darell took four crystals I had measured with my homebrewed
circuits and did his own measurements with ICM's professional
equipment, then sent them to Bill who did them on his vector analyzer.
So I had two good "controls" for my crystals and I compare the
results with my own measurements in the slide show.
below are to a couple of documents Mr. Carver was kind enough to
provide me. First are his notes from a crystal filter
presentation he did, I think at Dayton. Next is a sketched out
circuit he recommended to me for crystal measurements using the Hycas
amplifier I mentioned having built Note that his fixture puts the
crystal in a one ohm (!) environment, necessitating a lot of gain --
use for the Hycas.
Carver lecture notes PDF
Carver crystal test
circuit and notes PDF
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