US3838201A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency simulator for ew training device
Assignee: Individual
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Filing: 1973-06-25
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Granted: 1974-09-24
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Expires: 1993-06-25
Abstract
Abstract Frequency simulator apparatus for use with passive, electronic warfare (EW) training devices to render more effective and realistic signal recognition training of operators. A video switching network is connected between the output of a video tape recorder and the video circuits of a passive EW receiver set. Prerecorded radar video signals will not be displayed on the receiver set until the operator selects at the receiver set the proper frequency band and tunes the receiver to the proper frequency within that band to thereby actuate the switching network with a voltage indicating that the proper band has been selected and another voltage indicating that the proper frequency has been tuned to.
Inventors
- 👤 B Appling
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:50
CPC Classifications
G; G09; G09B; G09B9/00; G09B9/54
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
378 words
EW radar signal recognition training apparatus comprising: a source of prerecorded radar signals comprising video signals and audio frequency signals recorded simultaneously and preceded by a preamble comprising a train of high-frequency, audio bursts, said source having a video output and an audio output; passive EW receiver means comprising video display means, frequency tuner means for providing a DC voltage proportional to the frequency setting thereof, and frequency band selector means for providing a DC signal corresponding to the frequency band setting thereof; video switch means connected between the video output of said source and the input of said video display means; frequency discriminator means connected to the audio output of said source and being responsive to said train of highfrequency, audio bursts to produce a first DC output voltage each time a burst is coupled thereto, and further being responsive to said audio frequency signals to produce a second DC output voltage proportional to the frequency thereof; comparator means connected to the outputs of said frequency tuner means and said frequency discriminator means to compare said second DC output voltage with said DC voltage from said tuner, whereby said comparator means produces a first low-level signal when said second DC output voltage and said DC cvoltage are substantially equal; level-sensing amplifier means connected to the output of said frequency discriminator means and being responsive to said first DC output voltage to produce a high-level trigger output each time one of said bursts is sensed; binary counter means connected to the output of said amplifier means for counting said triggers and for producing an output count proportional to the number of said triggers coupled thereto; first logic gate means connected to the outputs of said binary counter means and said frequency band-selector means to produce a second low-level signal when said output counts and the output signals from said band selector means are equal; and, second logic gate means connected to the output of said comparator means and said first logic gate means to produce an output when said first and second low-level signals are coupled thereto in coincidence, said output being coupled to said video switch means to energize said switch means to an on condition whereby said video output is coupled to said video display means.
Claim 2
Dependent Claim
378 words
EW radar signal recognition training apparatus comprising: a source of prerecorded radar signals comprising video signals and audio frequency signals recorded simultaneously and preceded by a preamble comprising a train of high-frequency, audio bursts, said source having a video output and an audio output; passive EW receiver means comprising video display means, frequency tuner means for providing a DC voltage proportional to the frequency setting thereof, and frequency band selector means for providing a DC signal corresponding to the frequency band setting thereof; video switch means connected between the video output of said source and the input of said video display means; frequency discriminator means connected to the audio output of said source and being responsive to said train of highfrequency, audio bursts to produce a first DC output voltage each time a burst is coupled thereto, and further being responsive to said audio frequency signals to produce a second DC output voltage proportional to the frequency thereof; comparator means connected to the outputs of said frequency tuner means and said frequency discriminator means to compare said second DC output voltage with said DC voltage from said tuner, whereby said comparator means produces a first low-level signal when said second DC output voltage and said DC cvoltage are substantially equal; level-sensing amplifier means connected to the output of said frequency discriminator means and being responsive to said first DC output voltage to produce a high-level trigger output each time one of said bursts is sensed; binary counter means connected to the output of said amplifier means for counting said triggers and for producing an output count proportional to the number of said triggers coupled thereto; first logic gate means connected to the outputs of said binary counter means and said frequency band-selector means to produce a second low-level signal when said output counts and the output signals from said band selector means are equal; and, second logic gate means connected to the output of said comparator means and said first logic gate means to produce an output when said first and second low-level signals are coupled thereto in coincidence, said output being coupled to said video switch means to energize said switch means to an on condition whereby said video output is coupled to said video display means.
Claim 3
Dependent Claim
28 words
The apparatus of claim 1 wherein said frequency discriminator means includes an LR circuit preceded by amplification and voltage limiting stages and followed by rectifier and filter stages.
Claim 4
Dependent Claim
27 words
The apparatus of claim 1 wherein said comparator means includes a differential amplifier stage which drives a coincidence gate having an emitter follower connected at its output.
Claim 5
Dependent Claim
236 words
Passive apparatus for training radar personnel in signal recognition and comprising: a source of prerecorded signals of interest; operator-controlled receiver means for displaying said signals; switch means connected between said source and said receiver means and comprising: first discriminator and comparator means connected to an audio output of said source and to frequency potentiometer means of said receiver means for producing a first coincidence signal when an operator tunes said potentiometer means to a frequency substantially equal to that of said first audio output; second discriminator and counter means connected to said audio output for producing a pulsed output corresponding to the number of high-frequency audio bursts received from said audio output; first coincidence means connected to the output of said second discriminator and counter means and to the output of band select switch means of said receiver set for producing a second coincidence signal when an operator tunes said switch means to the frequency band corresponding to that of said bursts; second coincidence means connected to the outputs of said first discriminator and comparator means and said first coincidence means for producing a third coincidence signal wehn said first and second coincidence signals are received simultaneously; and, video switch means connected between a video output of said source and video display circuits of said receiver means and being responsive to said third coincidence signal to pass video signals to said receiver set for display thereof.
Claim 6
Dependent Claim
236 words
Passive apparatus for training radar personnel in signal recognition and comprising: a source of prerecorded signals of interest; operator-controlled receiver means for displaying said signals; switch means connected between said source and said receiver means and comprising: first discriminator and comparator means connected to an audio output of said source and to frequency potentiometer means of said receiver means for producing a first coincidence signal when an operator tunes said potentiometer means to a frequency substantially equal to that of said first audio output; second discriminator and counter means connected to said audio output for producing a pulsed output corresponding to the number of high-frequency audio bursts received from said audio output; first coincidence means connected to the output of said second discriminator and counter means and to the output of band select switch means of said receiver set for producing a second coincidence signal when an operator tunes said switch means to the frequency band corresponding to that of said bursts; second coincidence means connected to the outputs of said first discriminator and comparator means and said first coincidence means for producing a third coincidence signal wehn said first and second coincidence signals are received simultaneously; and, video switch means connected between a video output of said source and video display circuits of said receiver means and being responsive to said third coincidence signal to pass video signals to said receiver set for display thereof.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |