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Bliley Electric Company History: The Early Years, 1930-1955 - http://www.bliley.net/XTAL/
History of the company that invented and patented the overtone crystal, etch-to-frequency and variable crystals. Source for ads, engineering bulletins, patents and manuals. |
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Crystal Info - http://pages.cthome.net/fwc/XTAL.HTM
A handy historical chart of old crystal holders with dimensions, and suppliers. |
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Crystal Oscillators - http://www.qsl.net/n6ev/68-xtal.html
From N6EV. Tube oscillator schematics, and discussion. |
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Crystal Grinding - http://www.qsl.net/n6ev/ft243.txt
FT243 information compiled by Paul Carreiro, N6EV. |
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Technical Information - http://www.icmfg.com/technicaldata.html
A useful technical reference page for Crystals. |