Dynamic magnetic information storage or retrieval – General recording or reproducing – Specifics of equalizing
Patent
1976-09-30
1979-06-26
Canney, Vincent P.
Dynamic magnetic information storage or retrieval
General recording or reproducing
Specifics of equalizing
G11B 545
Patent
active
041594894
ABSTRACT:
A magnetic record reproducing system preamplifier includes an inductive choke in the emitter circuit of a first stage transistor amplifier whereby to provide a frequency responsive variable input impedance whereby to maintain a proper impedance relationship between the inductive transducer and the input impedance of the first stage amplifier. A second stage transistor amplifier is connected to the output of the first stage amplifier in cascode relationship, reducing the effective voltage gain of the first stage to substantially zero. The choke in the input circuit of the first stage amplifier acts as a degenerative feedback at higher frequencies, effectively reducing the bias current through the first stage transistor. The base emitter capacitance of the first stage transistor tends to resonate with the inductance of the transducer. The effective degenerative feedback at that first stage transistor tends to push that resonant frequency beyond the desired or useful frequency band of the system.
REFERENCES:
patent: 2861258 (1958-11-01), Walsh et al.
patent: 3026380 (1962-03-01), Reher et al.
patent: 3160824 (1964-12-01), Stair
patent: 3316360 (1967-04-01), Coleman, Jr. et al.
patent: 3513267 (1970-05-01), Trost
patent: 3585315 (1971-06-01), Shaifer
patent: 3781488 (1973-12-01), Byers
patent: 3927420 (1975-12-01), Hayashi et al.
Burton Lockwood
Canney Vincent P.
Honeywell Inc.
Marhoefer Laurence J.
LandOfFree
Magnetic record reproducing system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic record reproducing system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic record reproducing system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1560380