US3668673A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for telemetering d.c. signals
Assignee: Aerotherm Corp
•
Filing: 1970-09-23
•
Granted: 1972-06-06
•
Expires: 1990-09-23
Abstract
Abstract A telemetry transmitter where a d.c. voltage from for example a strain gage which is to be telemetered is converted to an a.c. square wave by a chopper. This amplitude modulated signal drives a voltage controlled oscillator which produces a frequency modulated signal which is then transmitted to a receiver by an antenna or wire.
Inventors
- 👤 Alan J Adler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:17
CPC Classifications
G; G08; G08C; G08C19/00; G08C19/12
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
118 words
Apparatus for telemetering d.c. signals including a transmitter coupled to a d.c. signal source said transmitter comprising: sub-carrier oscillator means; amplitude modulation means responsive to said d.c. signal and said sub-carrier oscillator means to produce an amplitude modulated output signal comprising a sub-carrier signal from said sub-carrier oscillator means and a modulation signal which is said d.c. signal; voltage controlled oscillator means directly responsive to said amplitude modulated output signal for generating a frequency modulated output signal whose amount of frequency deviation is proportional to said modulation signal and whose rate of deviation is equal to the frequency of said sub-carrier signal; and means coupled to said voltage controlled oscillator means for transmitting said frequency modulated output signal.
Claim 2
Dependent Claim
118 words
Apparatus for telemetering d.c. signals including a transmitter coupled to a d.c. signal source said transmitter comprising: sub-carrier oscillator means; amplitude modulation means responsive to said d.c. signal and said sub-carrier oscillator means to produce an amplitude modulated output signal comprising a sub-carrier signal from said sub-carrier oscillator means and a modulation signal which is said d.c. signal; voltage controlled oscillator means directly responsive to said amplitude modulated output signal for generating a frequency modulated output signal whose amount of frequency deviation is proportional to said modulation signal and whose rate of deviation is equal to the frequency of said sub-carrier signal; and means coupled to said voltage controlled oscillator means for transmitting said frequency modulated output signal.
Claim 3
Dependent Claim
18 words
Apparatus as in claim 1 where said amplitude modulation means provides 100 percent modulation of said sub-carrier signal.
Claim 4
Dependent Claim
21 words
Apparatus as in claim 1 where said amplitude modulation means chops said d.c. signal at the frequency of said sub-carrier signal.
Claim 5
Dependent Claim
14 words
Apparatus as in claim 3 where said sub-carrier oscillator is of the multivibrator type.
Claim 6
Dependent Claim
44 words
Apparatus as in claim 4 where said amplitude modulator means includes a pair of series connected field effect transistor having their gate terminals coupled to complementary outputs of the multivibrator oscillator and with two of their output terminals coupled to said d.c. signal source.
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) | 1975-06-06 | 1975-12-06 | 1976-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-06 | 1979-12-06 | 1980-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-06 | 1983-12-06 | 1984-06-06 | $7700.00 | Window Closed / Lapsed |