GB795098A - Telegraph apparatus employing a transistor amplifier - Google Patents
Telegraph apparatus employing a transistor amplifierInfo
- Publication number
- GB795098A GB795098A GB2924256A GB2924256A GB795098A GB 795098 A GB795098 A GB 795098A GB 2924256 A GB2924256 A GB 2924256A GB 2924256 A GB2924256 A GB 2924256A GB 795098 A GB795098 A GB 795098A
- Authority
- GB
- United Kingdom
- Prior art keywords
- relay
- circuit
- transistor
- signals
- output transistors
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
- H04L25/00—Baseband systems
- H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
- H04L25/20—Repeater circuits; Relay circuits
- H04L25/22—Repeaters for converting two wires to four wires; Repeaters for converting single current to double current
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Amplifiers (AREA)
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
Abstract
795,098. Code telegraphy. STANDARD TELEPHONES & CABLES, Ltd (International Telephone & Telegraph Corporation). Sept. 25, 1956, No. 29242/56. Class 40 (3). [Also in Group XL (c)] A frequency shift telegraph receiver comprises a limiter-discriminator arrangement 12, producing double current signals which are fed to a transistor converting amplifier 13 supplying single current signals to the selecting magnet of a teleprinter 14, and a circuit 11 which biases the amplifier into the mark condition when the signal is absent. The output from the discriminator 12 is negative on marking signals causing an input transistor 41 to be cut off and parallel connected output transistors 53, 54 to be conducting so that current flows in the selecting magnet 61 of a teleprinter. Space signals are positive and these cause the input transistor 41 to conduct and therefore the output transistors 53, 54 to be cut off so that the selecting relay 61 is released. A capacitor, resistance arrangement 56, 57 improves the operation of the relay and a zenner diode 55 limits the voltage peaks when the relay current is interrupted. It is stated that the relay circuit 11 which bases the input transistor to the marking condition in the absence of an input signal could be replaced by a transistor circuit. In an alternative circuit (Fig. 2, not shown) the output transistors are replaced by a junction diode.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2924256A GB795098A (en) | 1956-09-25 | 1956-09-25 | Telegraph apparatus employing a transistor amplifier |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2924256A GB795098A (en) | 1956-09-25 | 1956-09-25 | Telegraph apparatus employing a transistor amplifier |
Publications (1)
Publication Number | Publication Date |
---|---|
GB795098A true GB795098A (en) | 1958-05-14 |
Family
ID=10288399
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2924256A Expired GB795098A (en) | 1956-09-25 | 1956-09-25 | Telegraph apparatus employing a transistor amplifier |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB795098A (en) |
-
1956
- 1956-09-25 GB GB2924256A patent/GB795098A/en not_active Expired
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