REMOTE FUNCTIONAL CONTROL CIRCUIT

• US 3,614,321 A
• Filed: 03/07/1969
• Issued: 10/19/1971
• Est. Priority Date: 03/07/1969
• Status: Expired due to Term

• Current Assignee: Henry W. Shaw, Milton N. Lanford
• Original Assignee: Henry W. Shaw, Milton N. Lanford
• Inventors: Shaw, Henry W., Lanford, Milton N.
• Primary Examiner(s): Griffin, Robert L.
• Assistant Examiner(s): Handal, Anthony H.
• Application Number:
  US04/805,255
• Time in Patent Office: 956 Days
• Field of Search: 325/466,348,478,64,392,37 343/225,227,228 179/2A,1VC,1D,1SW,1VL 340/167A 353/15
• US Class Current: 381/105
• CPC Class Codes: H03G 1/02 Remote control of amplification, tone or bandwidth combined with remote tuning or selection of resonant circuits H03J
• CPC Class Codes: H03G 3/005 Control by a pilot signal H03G3/001 takes precedence

Abstract

We disclose a receiver of the type having an audiocircuit portion, a functional control circuit comprising a relay switch, a tone signal circuit having semiconductor switching means sensitive to presence of a certain tone signal, and additional series-connected semiconductor switch devices connected to the audiocircuit portion and to the first mentioned switching means, the presence of the certain tone signal causing the relay switch to be deactivated while enabling the audio circuit portion to function normally, but momentary interruption of the certain tone signal causing the relay switch to be activated and the audiocircuit portion to be concurrently squelched. Optionally operable switch means, connected in parallel with one of the additional series-connected semiconductor switch devices, is effective in its closed position to cause activation of the relay switch coterminously with continuance of the tone signal.

Claims

1. An audio squelch and remote control circuit comprising an audio circuit path having an audio amplifying stage, a tone signal circuit having a first semiconductive switch connected therein so as to be turned on responsively to the presence of a tone signal in said tone signal circuit, said first switch being also connected to said audio stage so that said audio stage is activated when said first switch is turned on, a second semiconductive switch and capacitance means connected in said tone signal circuit so that said second switch is turned off and turned on after a predetermined delay interval following turning on and turning off respectively of said first semiconductive switch, a relay having an actuating coil and a pair of semiconductive devices connected in series with each other and with said coil to a source of operating potential, one of said pair of semiconductive devices being connected to said second switch so that said one of said pair of semiconductive devices can be turned on as said second switch is turned off, the other of said pair of semiconductive devices being connected to said first semiconductive switch so that the other of said pair of semiconductive devices can be turned on when said first switch is turned off with the result that said pair of semiconductive devices are momentarily concurrently turned on upon a momentary interruption of said tone signal thereby causing energization of said relay coil.

2. The combination according to claim 1 wherein on-off switch means are connected in shunt relation to said other of said pair of semiconductive devices so that with said on-off switch means in closed position, said one of said pair of semiconductive devices is individually effective to cause energization of said relay coil so long as a tone signal endures in said tone signal circuit.

3. The combination according to claim 1 wherein an indicator lamp is connected in an energizing circuit in series relation to said one of said pair of semiconductive devices and energized under control of said one of said pair of semiconductive devices when turned on responsive to establishment of a tone signal in said tone signal path, to give visual indication of the presence of said tone signal in said tone signal path.

4. An audio squelch and remote control circuit comprising an audio circuit path having an audio amplifying stage, a tone signal circuit path having a first switching means operatively sensitive to the presence of a certain tone signal in said tone signal circuit path for activating said audio stage, a relay having contacts and an actuating coil therefor, a second switching means operatively responsive to said first switching means upon establishment and interruption of said certain tone signal, potential storage means operatively associated with said second switching mean for delaying actuation thereof responsive to a change in the operative condition of the first switching means, first and second switching devices connected in series with each other and with said actuating coil to a source of potential to thereby control actuation of said relay, said first switching device being responsive to said first switching means and said second switching device being responsive to said second switching means, said first and seconD switching devices being concurrently conducting only upon a momentary interruption of said tone signal.

5. The combination according to claim 4 wherein said first and said second switching devices are semiconductive devices the bias on which is respectively controlled according to the operative condition of said first switching means and said second switching means.

6. The combination according to claim 4 wherein is provided a charging circuit and a discharging circuit for said potential storage means, said charging circuit being established responsively to turn-off of said first switching means in consequence of interruption of a tone signal in said tone signal path to delay for a certain time the turn-on of said second switching means, and said discharging circuit being established responsively to turn-on of said first switching means in consequence of establishment of a tone signal in said tone signal path, to delay for a certain time the turn-off of said second switching means.

7. The combination according to claim 4 wherein said first switching device is turned on responsively to turn-off of said first switching means upon interruption of said tone signal, termination said second switching device is turned off responsively to turn-on of said second switching means following an interval of time delay effected by charging of said potential state means, the interval of time during which said first and second switching devices are concurrently turned-on determining the length of time the said coil is energized to activate said relay.

8. The combination according to claim 7 wherein an on-off switch is connected in shunt relation to said first switching device so that turn-on of only said second switching device effects energization of the coil of said relay, said second switching device being turned-on responsively to turn-off of said second switching means under control of said first switching means so long as a tone signal endures in said tone signal circuit.