actually, it is a lot easier to simply etch or grind away some of the
xtal, then check it with a grid dip oscillator for sharp dip, no need to
remount and test ;-) An old Hints and Kinks IIRC. This could be really
handy if you wanted to make a xtal filter and needed to really match and
control the xtal freq offsets (what, 3.5179 Mhz xtals from TV color burst
sources?) ;-)
and how about drilling a small hold in the holder so you could tread a
small bolt to put pressure on the xtal holder plates, shifting the xtal
freq. around like a xtal controlled VFO - but only a handful of khz ;-)
Still, very solid (pun intended) freq. source that can be varied around
enough to avoid QRM at minimal cost and effort for QRPers and so on? ;-)
Wasn't there a recent historical article in QST on the role of the quartz
xtal industry in WWII, how they figured out overtone osc. issues and so
on?
Given that some sources ask $12 and up for scanner and ham crystals, these
costs add up rather fast if you need to replace a bunch of xtals in a
scanner. So the search for alternatives seems quite worthwhile ;-)
regards bobm
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* Robert Monaghan POB 752182 Southern Methodist Univ. Dallas Tx 75275 *
********************Standard Disclaimers Apply*************************
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