GB1471318A - Communication apparatus for receiving data - Google Patents
Communication apparatus for receiving dataInfo
- Publication number
- GB1471318A GB1471318A GB2647174A GB2647174A GB1471318A GB 1471318 A GB1471318 A GB 1471318A GB 2647174 A GB2647174 A GB 2647174A GB 2647174 A GB2647174 A GB 2647174A GB 1471318 A GB1471318 A GB 1471318A
- Authority
- GB
- United Kingdom
- Prior art keywords
- transmitter
- encoder
- handset
- gate
- handle
- 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
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
- H04W88/02—Terminal devices
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/44—Transmit/receive switching
- H04B1/46—Transmit/receive switching by voice-frequency signals; by pilot signals
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
- H04B1/38—Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving
- H04B1/40—Circuits
- H04B1/54—Circuits using the same frequency for two directions of communication
- H04B1/56—Circuits using the same frequency for two directions of communication with provision for simultaneous communication in two directions
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M1/00—Substation equipment, e.g. for use by subscribers
- H04M1/72—Mobile telephones; Cordless telephones, i.e. devices for establishing wireless links to base stations without route selection
- H04M1/725—Cordless telephones
Landscapes
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Signal Processing (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
1471318 Radio telephone systems INTERNATIONAL MOBILE MACHINES CORP 14 June 1974 26471/74 Headings H4L and H4J A radio telephone system, includes a duplexer 16 and a conventional FM receiver and transmitter 12, 14 respectively for communication with a base station. To initiate a call the handset is removed from its hook to close a switch 41, Fig. 1, and open the circuit of line 42. Thus causes a scanner 36 to scan through the available channel frequencies and lock on to an idle channel which carries a 2000 Hz idle tone which is selected by filter 24 and passed to the scanner and to a gate 64. At the same time the impulse on line 42 turns on transmitter 14 and is also passed to a timer 52 which activates a 2150 Hz oscillator 54 for 250 milliseconds to modulate the transmitter accordingly. The signal from line 42 also enables an AND gate 60. The signals from the base station include the 2000 Hz idle tone and an 1800 Hz data tone for the particular user of the apparatus shown and these signals are passed to a decoder 30 which is arranged to separate tones and digits corresponding to the particular user from incorrect tones and digits which latter are supplied via line 32 to restart the scan. The 1800 Hz tone is selected by filter 26 and supplied to the decoder 30, to AND gates 60, 64 to cause them to conduct and to transmitter 14 to inhibit it from sending. AND gate 64 operates an alarm 76 and maintains the muting at 20. AND gate 60 operates a pulse encoder 80 which turns on transmitter 14 and sends a pulse via inverter 86 to sequentially operate encoder oscillator 54 and encoder disconnect 94 to send a signal to the base station for billing purposes. The output of encoder 95 also provides a signal to maintain circuit 20 in the unmuted state. The multi-frequency signalling pad 96 is then operated to dial a required number and communication is established via the microphone and receiver of the handset. When the handset is replaced on the hook a pulse is sent to the scanner 36 which resumes scanning and to a timer 102 which operates a flip-flop 104 to deactivate the encoder 54 and encoder disconnect 94 and turn off transmitter 14 via timer 116. Portable transmitter-receiver.-A housing 212 is provided with a handle 214 which is pivoted at 216 and may be locked in the closed position by a latch 218. A shelf 220 in the housing carries a multi-frequency signalling pad 222. This may be replaced by a dial or other pulse-generating system. The radio and encoding decoding equipment 226 is beneath the shelf. The handset 228 is held within the handle by a clip or hook 234 and when the handset is removed it releases a button 236 to activate the system. An aerial 240 in the handle is in the operative position when the handle is open.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU70124/74A AU483284B2 (en) | 1974-06-14 | 1974-06-14 | A communication system for receiving computerized data orthe like |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1471318A true GB1471318A (en) | 1977-04-21 |
Family
ID=3753444
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2647174A Expired GB1471318A (en) | 1974-06-14 | 1974-06-14 | Communication apparatus for receiving data |
Country Status (9)
Country | Link |
---|---|
AU (1) | AU483284B2 (en) |
BE (1) | BE817448A (en) |
CA (1) | CA1031038A (en) |
CH (1) | CH572684A5 (en) |
DE (1) | DE2432945C2 (en) |
FR (1) | FR2283599A1 (en) |
GB (1) | GB1471318A (en) |
NL (1) | NL187043C (en) |
SE (1) | SE382296B (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2167273A (en) * | 1982-06-01 | 1986-05-21 | Sideband Tech Inc | Radio frequency transmitter and method |
GB2184917A (en) * | 1985-12-04 | 1987-07-01 | Philip Smith | Security device for a telephone instrument |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1462279A (en) * | 1965-09-21 | 1966-04-15 | Cit Alcatel | Random carrier frequency radio links |
FR1552870A (en) * | 1967-08-11 | 1969-01-10 | ||
US3623106A (en) * | 1969-07-03 | 1971-11-23 | Motorola Inc | Multifrequency receiver employing tone-coded squelch with automatic channel selection |
FR2069778A5 (en) * | 1970-02-09 | 1971-09-03 | Siemens Spa Italiana | |
US3818481A (en) * | 1972-08-14 | 1974-06-18 | Codata Corp | Multiple address direct coupled communication and control current carrier system |
DD105363A1 (en) * | 1973-08-02 | 1974-04-12 |
-
1974
- 1974-06-14 AU AU70124/74A patent/AU483284B2/en not_active Expired
- 1974-06-14 GB GB2647174A patent/GB1471318A/en not_active Expired
- 1974-06-17 SE SE7407979-9A patent/SE382296B/en not_active IP Right Cessation
- 1974-06-17 CA CA202,627A patent/CA1031038A/en not_active Expired
- 1974-06-25 NL NLAANVRAGE7408553,A patent/NL187043C/en not_active IP Right Cessation
- 1974-06-26 CH CH878674A patent/CH572684A5/xx not_active IP Right Cessation
- 1974-07-09 BE BE146386A patent/BE817448A/en unknown
- 1974-07-09 DE DE2432945A patent/DE2432945C2/en not_active Expired
- 1974-07-10 FR FR7423978A patent/FR2283599A1/en active Granted
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB2167273A (en) * | 1982-06-01 | 1986-05-21 | Sideband Tech Inc | Radio frequency transmitter and method |
GB2184917A (en) * | 1985-12-04 | 1987-07-01 | Philip Smith | Security device for a telephone instrument |
GB2184917B (en) * | 1985-12-04 | 1989-11-15 | Philip Smith | A security device for a telephone instrument |
US4937860A (en) * | 1985-12-04 | 1990-06-26 | Philip Smith | Security device for a telephone instrument |
Also Published As
Publication number | Publication date |
---|---|
SE7407979L (en) | 1975-12-18 |
NL187043B (en) | 1990-12-03 |
NL187043C (en) | 1991-05-01 |
DE2432945A1 (en) | 1976-02-12 |
CA1031038A (en) | 1978-05-09 |
BE817448A (en) | 1974-11-04 |
SE382296B (en) | 1976-01-19 |
NL7408553A (en) | 1975-12-30 |
AU7012474A (en) | 1975-12-18 |
AU483284B2 (en) | 1975-12-18 |
CH572684A5 (en) | 1976-02-13 |
FR2283599B1 (en) | 1980-11-07 |
DE2432945C2 (en) | 1986-06-19 |
FR2283599A1 (en) | 1976-03-26 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |
Effective date: 19920614 |