Telephonic communications – Substation or terminal circuitry – Amplifying
Patent
1985-02-26
1987-07-14
Rubinson, Gene Z.
Telephonic communications
Substation or terminal circuitry
Amplifying
379387, H04M 160
Patent
active
046807896
ABSTRACT:
A transmit amplifier which also stabilizes the line direct voltage of the audio transmission circuit of a telephone set with respect to a reference voltage, the amplifier gain being adjustable to a high value by means of a resistor which does not affect the further properties of the audio transmission circuit. Variation of the line direct voltage by the offset current of the microphone pre-amplifier preceding the transmit amplifier, and by temperature fluctuations of the reference voltage, is greatly reduced by increasing the reference voltage and adding a temperature-dependent current source to a voltage divider which is comprised in the amplifier.
REFERENCES:
patent: 3748399 (1973-07-01), Matsuda et al.
patent: 3867576 (1975-02-01), Simonsen
patent: 3909548 (1975-09-01), Jacobson
patent: 4233474 (1980-11-01), Hishinuma et al.
patent: 4358644 (1982-11-01), Hubler
patent: 4394542 (1983-07-01), Hara et al.
patent: 4459553 (1984-07-01), Diller
patent: 4562309 (1985-12-01), Le Croff et al.
"Integrated Linear Basic Circuits", van Kessel et al, Philips Technical Review, vol. 32, No. 1, 1971, pp. 1-12.
Otten Henricus J. M.
Sijbers Peter J. M.
Van Der Plaats Petrie J.
Briody Thomas A.
Oisher Jack
Rubinson Gene Z.
Streeter William J.
U.S. Philips Corporation
LandOfFree
Audio transmission circuit comprising a transmit amplifier in th does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Audio transmission circuit comprising a transmit amplifier in th, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Audio transmission circuit comprising a transmit amplifier in th will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1432108