Found in a 1980s American documentation, this circuit has a current consumption of only 1 mA. The crystal can be from 100 kHz up to a few megahertz.
Found in a magazine 73 for radio amateurs, this circuit has two settings, one for the interval and the...
This good quality amplifier found in a 1982 documentation has a traditional complementary output...
A low frequency divider can be made using common unijunction transistors as shown by the figure...