Free Simple Circuit Diagram
This is a circuit of 90-125 MHz Crystal which is very useful for VHF/UHF converters. This circuit provide 5 to 15 mW output. High-quality fifth- or seventh-over-tone crystal type can be used in this circuit. Undesired oscillation never reach above 500 MHz because of Ferrite bead FB. Using regulated power supply and allowing crystal to operate at its natural series-resonant […]
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This is a metal locator circuit. This circuit is useful to detect metal. This circuit uses a AM radio and one-transistor oscillator. This circuit is inexpensive. The correct bias is provided by R1 and the frequency of oscillation is determined by search coil, C4 and C3. The search coil is formed by inductor which has varied inductance depend on the […]
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This is a 2 MHz crystal circuit using CMOS pair. This circuit is ideal for uses in digital watches and clock because this circuit has low power drain. The oscillator in this circuit is built by connecting the One CMOS transistor pair from CA3600E array with feedback pi network. This oscillator has stable performance with 2-MHz crystal. Here is the […]
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Using this circuit, we can accept positive or negative or differential control voltages. When the control voltage is zero, the output frequency is zero. To charge the timing capacitor C1 linearly, the 741 op amp forms a current source controlled by the voltage EC. The capacitor charges and discharges between 1/3 Vcc and 2/3 Vcc because NE555 is connected in […]
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