Just for reference: extract from the RSGB H/B, 4th. edition (1971).
Characteristics of quartz crystals.
Type of cut: X Y AT BC BT GT
Normal freq. range, MHz: 1-5 1-10 0.5-8 1-20 1-20 0.1-0.5
Temp. Co-eff. ( Hz/ MHz/ °C): -20 +75 0 -20 0 0
The temp. co. of the AT and BT cuts, given as zero, is only true at certain temperatures; at other temperatures, likely to be a small +ve or -ve value. Only the GT cut has a true zero temp. co.: 0 °C → 100 °C.
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(Presumably, the 'normal freq. range' refers to fundamental freq. operation and not an overtone).
It should also be borne in mind that that data was (presumably) up-to-date in 1971.
Al.
Characteristics of quartz crystals.
Type of cut: X Y AT BC BT GT
Normal freq. range, MHz: 1-5 1-10 0.5-8 1-20 1-20 0.1-0.5
Temp. Co-eff. ( Hz/ MHz/ °C): -20 +75 0 -20 0 0
The temp. co. of the AT and BT cuts, given as zero, is only true at certain temperatures; at other temperatures, likely to be a small +ve or -ve value. Only the GT cut has a true zero temp. co.: 0 °C → 100 °C.
-----------------------
(Presumably, the 'normal freq. range' refers to fundamental freq. operation and not an overtone).
It should also be borne in mind that that data was (presumably) up-to-date in 1971.
Al.
