US3735050A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical storage circuit
Assignee: Modern Telephones Ltd
•
Filing: 1971-07-16
•
Granted: 1973-05-22
•
Expires: 1991-07-16
Abstract
Abstract An electrical storage circuit suitable for use as a repertory dialler in a telephone system in which the digits of a number to be dialled are stored at respective addressed locations in a coordinate store constituted by active bistable devices as four bit words, and words read out from the store are applied via an inverter to a four bit counter which is stepped until each stage is set at 1 in synchronism with an output from a pulse generator to give a digital output according to an addressed word associated with a particular digit of a stored number at a rate governed by the frequency and duration of the clock pulse output from the generator.
Inventors
- 👤 A Mardas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:24
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/26; H04M1/27; H04M1/274; H04M1/2745; H04M1/27495
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
176 words
An electrical storage circuit including a random access store; a first input to the store; a plurality of digit switches; a decimal to binary code converter connected between said digit switches and said first input to the store to provide a parallel input to the store in the form of binary coded words according to the serial operation of the digit switches; a second input to the store for an address signal identifying the location of a respective group of said words in the Store; and means for reading a group of words out of the store according to a location in the store addressed by an address signal without removing the word information from the store, said means for reading out the group of words including a counter; an inverter connected between the output from the store and the counter; and a pulse generator having an output applied to control the counting down of the counter whereby a pulse train output corresponding to an output from the store according to an addressed word is provided.
Claim 2
Dependent Claim
176 words
An electrical storage circuit including a random access store; a first input to the store; a plurality of digit switches; a decimal to binary code converter connected between said digit switches and said first input to the store to provide a parallel input to the store in the form of binary coded words according to the serial operation of the digit switches; a second input to the store for an address signal identifying the location of a respective group of said words in the Store; and means for reading a group of words out of the store according to a location in the store addressed by an address signal without removing the word information from the store, said means for reading out the group of words including a counter; an inverter connected between the output from the store and the counter; and a pulse generator having an output applied to control the counting down of the counter whereby a pulse train output corresponding to an output from the store according to an addressed word is provided.
Claim 3
Dependent Claim
91 words
A circuit as claimed in claim 1 including an address code converter and a second counter, the address code converter and the second counter being connected in series between the address signal input and the second input to the store, a connection between the decimal to binary code converter and the second counter and a connection between the second gate and the second counter, whereby upon the writing in or reading out of a word from the store the second counter is stepped to address the location of a successive word.
Claim 4
Dependent Claim
51 words
A circuit as claimed in claim 2 including a keypad providing a signal corresponding to the address of the word and a binary encoder, the keypad being connected to the input of the binary encoder and the output of the binary encoder being connected to the input of the second counter.
Claim 5
Dependent Claim
51 words
A circuit as claimed in claim 3 including an impulsing relay and a third gate, a second output from the pulse generator and the output from the second gate being connected to the input to the third gate and the output from the third gate being connected to the impulsing relay.
Claim 6
Dependent Claim
22 words
A circuit as claimed in claim 4 wherein the output from the third gate is also connected to step the first counter.
Claim 7
Dependent Claim
76 words
A circuit as claimed in claim 2 including a Schmitt trigger circuit and an input to the store for a write signal, the Schmitt trigger circuit being in the connection between the decimal to binary code converter and the second counter and having its input connected to the output of the decimal to binary code converter, one output connected to step the second counter and the other output connected to the write input fro the store.
Claim 8
Dependent Claim
29 words
A circuit as claimed in claim 4 including a time delay circuit in the connection between the output from the second gate and the input to the third gate.
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) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |