US4475245A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transceiver
Assignee: Trio KK
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Filing: 1983-02-10
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Granted: 1984-10-02
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Expires: 2003-02-10
Abstract
Abstract An improvement in a transceiver having first and second carrier frequency oscillators for demodulation, a change-over device for making change-over of oscillation outputs between the first and second carrier frequency oscillators, a mixer for mixing the oscillation outputs from the first and second carrier frequency oscillators, and a switching circuit for connecting and disconnecting the input signal into, or output signal from, said mixer by on-off operations of the telegraphic transmission key to apply the signal to a low frequency amplifier of the transceiver.
Inventors
- 👤 Takashi Iimura
- 👤 Masaki Yanagihara
- 👤 Kouji Yokota
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 04:14
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/54; H04B1/403
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
118 words
A transceiver including: a transmission section and a receiver section comprising a demodulator means for supplying an audio signal to an audio amplifier and reproduction device; first and second carrier frequency oscillators; change-over means coupled to said first and second oscillators to select an output of one of said first and second carrier frequency oscillators and applying said output to said demodulator means; a mixer for mixing the oscillation outputs from said first and second carrier frequency oscillators; and a switching circuit for connecting and disconnecting the output signal from said mixer in response to on-off operations of a CW key to apply said mixer output signal to said audio frequency amplifier and reproduction device of the transceiver.
Claim 2
Dependent Claim
118 words
A transceiver including: a transmission section and a receiver section comprising a demodulator means for supplying an audio signal to an audio amplifier and reproduction device; first and second carrier frequency oscillators; change-over means coupled to said first and second oscillators to select an output of one of said first and second carrier frequency oscillators and applying said output to said demodulator means; a mixer for mixing the oscillation outputs from said first and second carrier frequency oscillators; and a switching circuit for connecting and disconnecting the output signal from said mixer in response to on-off operations of a CW key to apply said mixer output signal to said audio frequency amplifier and reproduction device of the transceiver.
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) | 1987-10-02 | 1988-04-02 | 1988-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-02 | 1992-04-02 | 1992-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-02 | 1996-04-02 | 1996-10-02 | $7700.00 | Window Closed / Lapsed |