Adjustable frequency bipolar square wave generating circuit

Claim 2

A circuit for energizing an output circuit to the lowfreuqency pulses, said circuit including: an input circuit of direct current; an oscillator connected across said input circuit for providing high-frequency alternating current; first means operatively associated with said oscillator and said output circuit and energized by said high-frequency alternating current for providing a positive going pulse across said output circuit each time said oscillator is rendered operable; a pulse circuit connected across said input circuit and operatively associated with said output circuit for providing negative going pulses across said output circuit; a multivibrator operatively associated with said oscillator and said pulse circuit for rendering said oscillator and said pulse circuit alternately operative at a frequency lower than the frequency of oscillation of said oscillator, said multivibrator including first and second transistors having emitter collector circuits connectable in parallel across said input circuit and each having an output and an input circuit, control means connecting the output circuit of each of said transistors to the input circuit of the other transistor for causing the emitter collector of each transistor to be rendered nonconductive for a predetermined period of time when the emitter collector circuit of the other transistor is rendered conductive, and blocking means operatively associated with said control means and connected between the input and output circuits of each transistor for preventing each transistor from rendering its own emitter collector circuit nonconductive.

Claim 3

The circuit of claim 1, wherein said control means includes adjustable means for varying said predetermined period of time.

Claim 4

The circuit of claim 2, wherein said transistors have resistances connected in series between their collectors and one side of said input circuit of direct current, the common connection of the collector of each transistor and the resistance connected thereto constituting the output circuits of said transistors and the bases of said transistors constItuting their input circuits, said control means comprising a capacitor connected between the output circuit of each transistor and the input circuit of the other transistor, and discharge path means for said capacitors connected between said capacitors and said one side of said input circuit of direct current.

Claim 5

The circuit of claim 3, said blocking means comprising unidirectionally conducting means connected in said discharge path means for preventing flow of current from one capacitor to the other through said discharge path means and permitting flow of current from said capacitors through said discharge path means to said one side of said input circuit.

Claim 6

The circuit of claim 4, wherein said adjustable means comprises a variable resistance, said discharge path means including said variable resistance.

Claim 7

The circuit of claim 1, wherein said first transistor and said second transistor each have a collector, a base and an emitter, the emitters of said transistors being connectable to one side of said input circuit of direct current; said control means including a first resistance for connecting the collector of said first transistor to the other side of said input circuit; a second resistance for connecting the emitter of said second transistor to said other side of said input circuit; a first capacitor and a third resistance connected in series between said other side and a first common connection of the emitter of said first transistor and said first resistance; a second capacitor and a fourth resistance connected in series between said other side and a second common connection of the collector of said second transistor and said second resistance; means connecting the base of said first transistor to a third common connection of said fourth resistance and said second capacitor; means connecting the base of said second transistor to a fourth common connection of said first transistor and said third resistance; and a common discharge path means for said capacitors connected between said other side of said input circuit and said third and fourth common connections, said blocking means including unidirectionally conducting means connected reversely in series between said capacitors and said discharge path means for preventing flow of current from one capacitor to the other and for permitting flow of current from each of said capacitors through said discharge path means to said other side of said input circuit.

Claim 8

The circuit of claim 6, wherein said discharge path means includes a variable resistance for varying the period of discharge of said capacitors whereby the frequency of oscillation of said multivibrator may be varied.