Loudspeaker telephone apparatus
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United States of America Patent
Stats
-
Feb 17, 1981
Grant Date -
N/A
app pub date -
Jul 9, 1979
filing date -
Jul 9, 1979
priority date (Note) -
Expired
status (Latency Note)
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Abstract
The loudspeaker telephone apparatus consists of a hybrid circuit which interconnects a telephone line and its line balance impedance with receive and transmit amplifiers. These amplifiers are connected to a bridge circuit, the arms of which are formed from two pairs of similar coil groups located in two multi-filar moving coil loudspeakers. The coil groups in one loudspeaker are connected in series aiding while the coil groups in the other loudspeaker are connected in series bucking. In one arrangement, the bridge circuit may be connected directly to the amplifier, the receive amplifier being connected across the pair of coils in each loudspeaker and the transmit amplifier being connected across the junction between the pair of coils in each loudspeaker. In another arrangement, a second hybrid circuit is used to connect the bridge to the amplifiers which are connected to the hybrid by its amplifier terminals. One coil group in the bridge is connected to the line terminals of the hybrid and a balance RC impedance is connected to the balance terminals.
First Claim
Family
- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
- TECHNICAL UNIVERSITY OF NOVA SCOTIA
International Classification(s)
Inventor(s)
| Inventor Name | Address | # of filed Patents | Total Citations |
|---|---|---|---|
| Hastings-James, Richard | Halifax, CA | 2 | 33 |
| Holbrook, George W | Tantallon, CA | 2 | 33 |
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| Fee | Large entity fee | small entity fee | micro entity fee |
|---|---|---|---|
| Surcharge after expiration - Late payment is unavoidable | $700.00 | $350.00 | $175.00 |
| Surcharge after expiration - Late payment is unintentional | $1,640.00 | $820.00 | $410.00 |
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