US2441958A - Communication system - Google Patents

Communication system Download PDF

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Publication number
US2441958A
US2441958A US545260A US54526044A US2441958A US 2441958 A US2441958 A US 2441958A US 545260 A US545260 A US 545260A US 54526044 A US54526044 A US 54526044A US 2441958 A US2441958 A US 2441958A
Authority
US
United States
Prior art keywords
tube
condenser
circuit
grid
potential
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 - Lifetime
Application number
US545260A
Other languages
English (en)
Inventor
Rosa Louis A De
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
STC PLC
Federal Telephone and Radio Corp
Original Assignee
Standard Telephone and Cables PLC
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority to BE475385D priority Critical patent/BE475385A/xx
Application filed by Standard Telephone and Cables PLC filed Critical Standard Telephone and Cables PLC
Priority to US545260A priority patent/US2441958A/en
Priority to GB18205/45A priority patent/GB596052A/en
Priority to FR950767D priority patent/FR950767A/fr
Priority to ES0182268A priority patent/ES182268A1/es
Application granted granted Critical
Publication of US2441958A publication Critical patent/US2441958A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B14/00—Transmission systems not characterised by the medium used for transmission
    • H04B14/02—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K3/00—Circuits for generating electric pulses; Monostable, bistable or multistable circuits
    • H03K3/78—Generating a single train of pulses having a predetermined pattern, e.g. a predetermined number
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K7/00—Modulating pulses with a continuously-variable modulating signal
    • H03K7/06—Frequency or rate modulation, i.e. PFM or PRM
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B14/00—Transmission systems not characterised by the medium used for transmission
    • H04B14/02—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation
    • H04B14/026—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation using pulse time characteristics modulation, e.g. width, position, interval

Definitions

  • My invention relates to communicating systems, and more particularly to a simpliediorm of pulse generating system that is particularly suited for use in portable transmitters.
  • radio trans-f mitting equipment must be kept within certain prescribed limits both as to weight and to the number and variety of circuit elements employed. While this is often the case in apparatus intended for use on aircraft, itis almost universally" ior repair thereof is greatly facilitated. Further-'i15- more, a reduction in the number of circuit elements utilized correspondingly reduces the possibilityof electrical or mechanical failure of the transmitter.
  • a lead II connects the anode 9 of triode 3 to' is varied in accordance with the envelope of the signal representing the intelligence to be transmitted.
  • Fig, 2 is a set of curves useful in explaining the operation oi the system of Fig. 1;
  • Fig. 3 is a schematic circuit diagram of one form of receiving system that may lbe employed inconjunction .with the transmitting system of Fig. 1.
  • a pulse transmitting system including a microphone or other sound pick-up device I connected to an amplifier 2.1
  • a gasffilled triode 3 such, for example, as an RCA 884 has its grid d connected through a coupling condenser to the output of amplier 2.
  • a resistor 5 provides a negative bias from voltage C ⁇ on grid 4 for a purpose to be hereinafter described.
  • -l Y A Between the cathode 6 of triode 3 and ground is connected a resistor l of fairly high value, Asay forV example '75,000 ohms.
  • a condenser 8 is shunted across resistor
  • Anode 9 of triode 3 is provided with a D. C. potential of positive polarity from a suitable source. For the purpose of illustration, let this plate potential be equal to 150 volts. Between anode 9 ⁇ and the source of plate potential Yis connected IaY resistor Il) of fairly low value, say
  • amplifier I2 passes through a clipping circuit I3 to an R. F. translator I4 and is thentransmitted from an- Y tenna I5.
  • the horizontal line I6 represents the normal striking potential oi tube 3 as determined by its bias, in the present example approximately -151/'2
  • the grid voltage is of constant value, in which case the series of points 2E!A representing Vperiodic maximum" charged conditions of condenser 8 will be'edually spacedv apart in time, this spacing being, ot course, determined by the" time constant of the resistance-corldenserV combination 'I- as well as bythe operating characteristics of, and the voltages.on, the particular tube employed.
  • theV normal striking potential oi tube 3; vvillfY be varied. This is illustratedfby. the wave 24 of curve a, which shows the signal voltage superposed on the grid bias voltage. Due to, this variance in the striking potentiaLvthe time duringj which condenser 3 ⁇ discharges before the striking potential is reached willi vary correspondingly. As shown for example inportion.25 o f waveV I'I, the discharge time of the condenser isl applieciably shortened, resulting a change, in the recurrence rate oi points 2:0,A along extinction level 2I.
  • pulses of curve b in that casebeingapplieddirect to translator la are used ⁇ to modulatefa-carrier wave in a conventional translating device I4 whereby a series of pulses 30 of R. F. energy as shown in curve d is produced for transmission from antenna I5.
  • a system such as shown in Fig. 3 may be employed.
  • This system comprises an R. F. detector and amplifier 3! which may be of any suitable type.
  • the output of detector and amplifier 3l is applied to an integrating circuit 32 which reproduces the envelope of the original audio, Wave as applied to grid 4 of Vtriode 3 in Fig; 1*:
  • the audio wave mayrthen be used to energize a reproducing apparatus such as the tem, it is to ⁇ be clearly understood that this discription is made by way of example only and not as a limitation on the scope of my invention asset forth in the objects and the accompanying claims.
  • a pulse modulator system comprising afreely-running relaxation. oscillator including; a gridcontrolled gaseous discharge tube,AY an anodecathode circuit coupled tosaid; tube, asource of potential coupled to4 theanodefcathode. circuit of said tube, time-constant means coupledftothe anode-cathodeV circuit Vand including. a condenser adapted-tobenorrnally chargediand: discharged.-y at a rate controlled; byV thepotential on thel grid kof sa idtube, meansfor biasing said.
  • Apulsemodulator. system according toclaim 11 wherein said; time; constant; means.. is. a. circuit including a resistor in. parallel with; saidV condensensaid circuit; being connected inseries in the anodefcathode circuit, said. condenser being charged ,uponignitionoigsaidvr tubeanddischarged through said resistor.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Other Investigation Or Analysis Of Materials By Electrical Means (AREA)
  • Electrostatic Spraying Apparatus (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
US545260A 1944-07-17 1944-07-17 Communication system Expired - Lifetime US2441958A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
BE475385D BE475385A (en(2012)) 1944-07-17
US545260A US2441958A (en) 1944-07-17 1944-07-17 Communication system
GB18205/45A GB596052A (en) 1944-07-17 1945-07-16 Pulse generating and/or modulating system using a gas-filled electron discharge tube
FR950767D FR950767A (fr) 1944-07-17 1947-08-01 Systèmes de communications radioélectriques
ES0182268A ES182268A1 (es) 1944-07-17 1948-02-11 MEJORAS EN SISTEMAS DE COMUNICACIoN

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US545260A US2441958A (en) 1944-07-17 1944-07-17 Communication system

Publications (1)

Publication Number Publication Date
US2441958A true US2441958A (en) 1948-05-25

Family

ID=24175509

Family Applications (1)

Application Number Title Priority Date Filing Date
US545260A Expired - Lifetime US2441958A (en) 1944-07-17 1944-07-17 Communication system

Country Status (5)

Country Link
US (1) US2441958A (en(2012))
BE (1) BE475385A (en(2012))
ES (1) ES182268A1 (en(2012))
FR (1) FR950767A (en(2012))
GB (1) GB596052A (en(2012))

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2495768A (en) * 1947-05-12 1950-01-31 Int Standard Electric Corp Electric pulse modulator

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1887237A (en) * 1929-05-31 1932-11-08 Rca Corp Signaling system
US2227596A (en) * 1938-03-31 1941-01-07 Rca Corp Signaling system
US2280707A (en) * 1940-05-31 1942-04-21 Rca Corp Apparatus for and method of frequency modulating
US2288554A (en) * 1939-06-05 1942-06-30 Philco Radio & Television Corp Synchronizing system and method
US2292100A (en) * 1940-08-30 1942-08-04 Rca Corp Square wave generator
US2329137A (en) * 1941-05-23 1943-09-07 Rca Corp Deflection generator

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1887237A (en) * 1929-05-31 1932-11-08 Rca Corp Signaling system
US2227596A (en) * 1938-03-31 1941-01-07 Rca Corp Signaling system
US2288554A (en) * 1939-06-05 1942-06-30 Philco Radio & Television Corp Synchronizing system and method
US2280707A (en) * 1940-05-31 1942-04-21 Rca Corp Apparatus for and method of frequency modulating
US2292100A (en) * 1940-08-30 1942-08-04 Rca Corp Square wave generator
US2329137A (en) * 1941-05-23 1943-09-07 Rca Corp Deflection generator

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2495768A (en) * 1947-05-12 1950-01-31 Int Standard Electric Corp Electric pulse modulator

Also Published As

Publication number Publication date
BE475385A (en(2012))
FR950767A (fr) 1949-10-06
GB596052A (en) 1947-12-24
ES182268A1 (es) 1948-04-01

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