US2458558A - Radiotelephone equipment - Google Patents

Radiotelephone equipment Download PDF

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US2458558A
US2458558A US686265A US68626546A US2458558A US 2458558 A US2458558 A US 2458558A US 686265 A US686265 A US 686265A US 68626546 A US68626546 A US 68626546A US 2458558 A US2458558 A US 2458558A
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switch
relay
contacts
receivers
control unit
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George G Bradley
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RCA Corp
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RCA Corp
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W84/00—Network topologies
    • H04W84/02—Hierarchically pre-organised networks, e.g. paging networks, cellular networks, WLAN [Wireless Local Area Network] or WLL [Wireless Local Loop]
    • H04W84/04—Large scale networks; Deep hierarchical networks

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  • This invention relates to-radio-telephone equipment.
  • the invention has particular application in two-way radiotelephone service where it is required to operate between ships and on ship-to-shore service.
  • the invention is well adapted to the communication needs of ships which ply our inland water ways, such as rivers and lakes.
  • My invention is exemplified in certain radiotelephone equipment which has been built and successfully tested and which, as a specific embodiment, comprises transmitting circuits pretuned to as many as six radio frequency channels and six radio receivers, also pre-tuned.
  • the main body of the equipment including the radio circuits, is usually located at some point remote from the operators station. It is therefore required that it be completely operated by remote control.
  • two telephone stations are installed, one, say, in the pilot house, and the other in the radio operators cabin or captains quarters.
  • the different transmitting circuits and receivers are adjusted for service on assigned carrier waves, such as have been provided by the Federal Communications Commission for use on the Mississippi River and its tributaries, or on the Great Lakes.
  • the frequency range is within the limits of 2000 to 9000 kilocycles.
  • the power output of the transmitter is preferably in the 75 watt range.
  • the equipment has been proven satisfactory for service over distances as great as 800 miles. In pla and answering calls a frequency channel is usually chosen among six that are available whereby optimum conditions of communication may be chosen according to the time of day and with respect to the distance between stations.
  • the transmitter of which is serviceable with a minimum of delay for answering a call, and which will give satisfactory service over distances up to 800 miles.
  • each receiver being tuned to a difierent frequency channel and their outputs being impressed upon aloud speaker or a selective .rcall responsive device which responds to specific code signals and causes an alarm to be sounded upon reception of its code number.
  • FIG. 1 a single circuit diagram is shown by Figs. 1 and 2.
  • Fig. 215 to be placed on the right'hand side of Fig. 1, so that the conductors which appear to run from one figure to the other maybe placed in registry.
  • this figure in its entirety represents a control unit A for one telephone station.
  • This control unit comprises a hook switch IOI whereon a hand-set I02 may be hung when not in use.
  • the control unit also includes a loud speaker I03 which is principally used for continuous monitoring of incoming calls on the three medium or low frequency channels.
  • a bell I04 is also provided in the control unit. As will be explained hereinafter, this bell is sounded by relay operation whenever a selective ringer I05 responds to code signals.
  • This selective ringer is preferably connected through a ringer amplifier I06 to the output terminals of three receivers D, E and F which are tuned to the higher frequencies.
  • a channel selector switch having a multiplicity of ganged contact wipers and cooperating contacts' wafers, lettered a to 1 inclusive, is provided for use of the equipment on any of six radio frequency channels, numbered I to 6 inclusive.
  • the gang switch also has a position for stand-by operation, so that continuous monitoring of incoming calls may be had on any of the six receivers ,three of which would impress their calls upon the loud speaker and the other three of which would be responsive by way of soundingthe alarm through the selective ringer I and bell I04.
  • control unit A shown in Fig. 1 may be the sole telephone station on board, but preferably two such units are provided.
  • Fig. 2 therefore I have shown as a block diagramv asecond control unit B the components of which will be understood to be exact duplicates of what is provided in control unit A.
  • the radio equipment is housed in a single cabinet which may be located wherever spacev can be conveniently found on shipboard.
  • This cabinet contains the radio circuits of the transmit,- ters and receivers, also certain switching devices which are remotely controlled from the control stations. Furthermore it houses the selective ringer I05. and a motor-generator for the transmitter power supply.
  • the motor-generator is not shown, but it will be understood that it requires starting mechanism for which a control circuit 209 is provided.
  • the receivers are operated from the ships D. C. power line.
  • the motor-generator is operated only when carrying on a conversation and provides anode, screen and negative biasing voltages for the transmitter tubes.
  • the junction box contains only the relays 60I, 602 and 604, the first two relays beingparallel-connected.
  • the control unit The remote control unit with which the handset I02 is associated is provided with a switch I01 having connections 8
  • Switch I I0 is; provided for choosing between loud speaker and, earphone receoption.
  • the hand-set, I02 is provided with.
  • a push-button I I I- which must be depressed when talking.
  • the pushbutton circuit may be traced from ground through conductor 30, contacts of relay 60-2, the coil. of relay- I12 and thenceto the negative terminal-C of the transmitter power supply, in which the +C' is ground potential.
  • Thev relay II'2 operates two movable contacts b, and e. which. are associated with front contactsa, and cl respectively, and contact e normally rests.
  • resistor I22 4700 ohms
  • resistor I57 5 ohms
  • the carrier wave is not propagated because of a positive potential applied to the cathodes just mentioned.
  • This positive potential results from the voltage drop (approximately volts)- through resistor I22 which carries a bleedercurrent derived from a voltage divider (not shown but indicated by terminal T) connected across the anode potential source terminals in the motor generator, the negative terminal being grounded.
  • resistor I 5l which is; sufficient to energize the microphone.
  • Function (4) of the relay H2 is: to open the circuit between the. negative line terminal -L and all of the receiver gain control circuits, thus silencing the receivers while talking.
  • This circuit when normally closed may be traced from relay contacts II2e, -f through relay contacts I I'3fe-e, through conductor I'I8, through branched rheostat. elements H5, H6 and II "I to certain contacts of the channel selector which connect with gain control circuits 43, 44 and 45 leading to the cathodes of R. F. and I. F. amplifier stages (not shown) in the low frequency receivers A, B and C.
  • the connections to corresponding cathodes in receivers D, E and F may also be traced from conductor II'8 through other contacts of the channel selector and through conductors #0, M and 42 to the high frequency receivers.
  • Relay II4' when operated as a slave to relay I I2 performs further functions thus:
  • Function (2). of relay I- I4 is to open the circuit. at its contacts c-b so as to disconnect the antenna from conductor I, 2;'I having branches to each of the signal input terminals of the six receivers. During talking periods, therefore, no signal can. reach the receivers.
  • Function (3) is carried, out by closure of contacts de, thus grounding the input circuits of the receivers: for the purpose. of noise suppression.
  • Function (4); isfulfilled by closure of contacts I I4J'--g andismerely contributory to the performance (as above described) of function (3) of relay II2, that is, to close the microphone circuit.
  • One virtue in the double make; and break of this circuit is, to minimize key clicks.
  • The. operation, of; relay H14 is delayed by a, few microsseconds. with respect. to that of re.- lay II2.
  • Position is used for maintaining stand-by conditions in which the output circuits of the three low frequency receivers A, B and C are connected through conductor 39, switch wafer 71. and thence through contacts of the hook switch II to the loud speaker I I33. Also the output circuits of the high frequency receivers D, E and F are connected through conductor 38 and switch wafer i and thence through conductor 31 to the ringer amplifier I06.
  • the gain control circuits for each of the receivers F, E, D, C, B and A is brought out individually through one of the conductors 40 to 45 inclusive and is connected to a wiper On one of the wafers f, e, d, c, b and a respectively.
  • a gang-controlled rheostat comprises adjustable resistors H5, H6 and II! by which the volume of three receivers can be manually set.
  • resistor H5 at the left hand terminal is connected to different stationary contacts on wafers 1, c, b, a, e and d.
  • Resistor H6 is connected to one contact at the 0-position on wafer c and resistor II"! is connected only to the contact at the 0-position on wafer b.
  • the right hand terminals of these three rheostat resistors are connected in common through conductor H3 to movable contact 6 on relay H3, thence through back contacts 7 of the two relays H3 and H2 and through movable contact II 2e to the L terminal which supplies cathode potential to certain amplifier stages in all of the receivers.
  • these are the radio frequency and the first intermediate frequency amplifier stages.
  • the gain control circuits for the high frequency receivers D, E and F are connectable directly to conductor H8 when the channel selector switch is set to any of the positions 0, 3, 4 or 5. Thus for stand-by conditions and when using any one of the low frequency channels for a communication the high frequency receivers are all operated at full gain.
  • switch position 1 the gain control circuit for receiver D may be traced through conductor 42, wafer d, resistor H5, conductor H8 and thence through relay contacts to the ,L terminal. Silencing of all the other receivers is then accomplished by opening their gain control cir cuits. So switch position 1 is useful for communicating on the channel to which receiver D is tuned.
  • the gain control circuit for receiver E is connected through conductor 4
  • Switch wafer g has its stationary contacts I to 6 inclusive connected individually to pilot lamps I20 for clearly indicating the setting of the channel selector switch when it is moved away from the 0-position.
  • the Wiper on wafer g feeds current to a selected lamp from a 6-volt source upon closure of contacts dand e when the hand-set I02 is lifted from its hook IDI.
  • pilot lamps IZII which stand in channel positions 1, 2 and 6 respectively are also connected through conductors 35, 34 and 33 respectively to contacts in the selective ringer unit I05.
  • Unit I05 is arranged and adapted to close these circuits selectively when it is actuated by the proper sequence of audio frequency call signals;
  • the signal pulses are of 600 and 1500 cycle modulation which are alternated at a rate of 4 to 5 /2 cycles per second.
  • the selector set on each ship may be arranged to respond to any one of a number of five-digit codes, so that the selective calling of any one of a group of stations operating on the same carrier frequency is possible.
  • the terminating pulses of the call signalsign ify the communication channel to be used, and by illuminating a particular one of the pilot lamps I20 the answering party is enabled to turn his channel selector switch to the proper position for answering the call on any one of the high frequency channels.
  • Switch wafer 7 on the channel selector switch has connections through a cable to individual contacts of a motor-driven rotary gang switch IZBat the main equipment unit.
  • the details of construction and operation of switch I26 are not herein given since they are covered in my copending application Ser. No. 679,343 filed June 26, 1946.
  • the setting of switch I26 is accomplished under control of a relay H3 which is in circuit with a selected conductor in cable 5!] and operates to keep the armature of motor I28 energized until the setting of switch I26 corresponds with that of the wiper on wafer 7' of the channel selector switch.
  • the gang switch I26 performs numerous functions, such as selecting the proper radio frequency tuning elements in the transmitting equipment and connecting the proper output circuit to conductor I24 for feeding outgoing signals to the antenna I23.
  • the gear train through which the motor I23 drives the gang switch I26 includes preferably a worm. reducing gear I29 and a Geneva movement I30.
  • the channel selector switch In order to listen to a particular receiver the channel selector switch must be set to the desired channel. This connects the cathodes of the selected receiver to the volume control rheostat I I5 and connects the output of this receiver to the loud speaker circuit.
  • the high frequency receivers D, E and F remain connected to the selective ringer, as hereinabove explained. And when one of the high frequency receivers is selected for a communication, then all'of the non-selected re ce-ivers are silenced by opening their gain control circuits. This arrangement has been found to meet the practical requirements of two-way radio telephone service in the Mississippi River and Great Lakes regions.
  • the six sets of pretu-ned transmitter circuits are preferably of atypewherein carrier power in the '7'5-watt range is generated by a crystal controlled tuned anode circuit oscillator.
  • anode tank circult is provided for each transmitting channel. These circuits are switched by wafers on the gang switch I26.
  • the selected, tuned transmitter unit is connected to a number of parallel-connected power amplifier stages. Audio frequency output from the modulator unit I 2I is applied to the screen grids and anodes of those power amplifier stages. The modulate-d output is then coupled to one of six sets of antenna tuning circuits connections being made through still another wafer of the motor-driven gang switch. Finally, the antenna conductor I247 is connected to the selected antenna tuning circuit, through one more wafer of the gang switch in unit I26. All these details of transmitter circuit switching may readily be worked out for different transmitter circuit designs by those skilled in the art. For purposes of this: disclosure, therefore, it is preferred to symbolize by block diagram the transmitter circuits I25 and the gang switch l'26 for channel frequency selection.
  • the motor-driven gang switch- I2'6 be capable of automatic adjustment to any position corresponding to positions 1 to 6 inclusive in the manually operable channel selector switch at the control unit.
  • the motor-driven switch I26 is capable of rotation in one direction from any previous setting to. any desired new setting, it matters not where it is set at the time of shutting down the transmitter and of turning the manually operable switch to the stand-by position.
  • the motor-driven gang switch has no stand-by position, for it needs none. But itv always assumes a position corresponding to positions 1 to 6 inclusive of the manually operable gang, switch, the latter exercising its control through its wafer 7'.
  • the earphone, microphone, modulator and pushbutton The cord I3I for the hand set H32 contains separate conductors for the microphone, the earphone and. the push-button III. Also for these three elements there is a common return conductor connected to ground.
  • the output from one of the receivers is brought through one or the other of the conductors 38-39 to the wiper on channel selector switch Wafer h and thence through conductor I32, through closed contacts I) and a of hook switch IIH, and manual switch IIEl, this last being thrown to make connection with the earphone.
  • the return circuit is through ground to a grounded terminal of the secondary winding (not shown) on the receiver output transformer. While listening the antenna I23 is connected through normally closed contacts b and o of relay I I4 to all of the receiver input terminals in parallel.
  • the microphone is connected. through a circuit which may be traced from ground through the microphone, thence through the modulator unit I2I, and through a 5. ohm resistor I51 to ground. By closing contacts f and g of b and a of relay II2v a. suitable voltage drop is produced through resistor I5! which constitutes the D. C. supply to the microphone, as heretofore indicated.
  • the push-button I I I- is connected through conductor 30. to the winding of relay I I2 and thence to the C terminal of the transmitter power supply.
  • the +C terminal is grounded.
  • the transfer functions of relays H2 and IM as controlled by the push button I I I have already been described. It should here be noted, however, that the receivers can all be silenced in two Ways-one by operation of the push-button-controlled relay II2 which opens its contacts e and f; the other by operation of relay I I3 which opens its contacts e and ,f. In the latter case the receivers are silenced during the movement of the channel selector switch I26 from one to another position. These four relay contacts just mentioned when normally closed complete the receiver gain control circuits to the L power supply terminaL, as hereinabove set forth.
  • the hoolc switch When the hand-set I02 is lifted from, its hook IllI contacts of the latter operate as follows: Contacts b and 0 open to silence the loud speaker. If loud speaker operation is preferred to earphone reception while engaged in a conversation, then switch H0 may be thrown to the proper position for that purpose. Closure of switch-hook contacts a and b connects the receiver output to the movable contact on switch I-IIl.
  • Closure of switch-hook contacts at and e supplies potential froma +6-volt source terminal to the wiper on channel selector switch wafer 9 so as to light up one of the channel indicating pilot lamps I220.
  • the negative terminal of this 6-volt source is the same as the -L terminal. So the return circuit common to all the lamps I20 joins that of the bell I64 and includes conductor -32, contact ,1 on relay 602 which is directly connected to the -L terminal.
  • switch-hook contacts 1 and g connects conductors 9 and 36 to conductor 46, whereby +L potential is supplied (1) through switch water 9' and conductor 50 to relay II 3 for operating the motor-driven channel selector switch I26; (2) through conductor 46 to terminal 209 on the starter coil of the motor-generator; and (3) through conductor 46 to the Winding of a so-called lock-out relay 604- in the junction box.
  • the function of this relay will presently be explained.
  • the three branch circuits closed by switch-hook contacts f and g. are all returned to. the L line terminal.
  • junction boa The junction boa:
  • the junction box contains terminal boards for the inter-connecting cables which are necessary for remote control of the. radio equipment from either of two remote control stations.
  • the junction box also contains the necessary relays B01, 602 and 604 for switchingthe control circuits from one remote control unit to the other.
  • each relay As shown in Figure 2 the relays EDI and 602 have their windings connected in parallel and each relay operates nine movable contacts most of which engage with both front and back stationary contacts. Practically it is preferred to use three relays in place of relays GUI: and 602 in order that the spring load of each relay coil may not be excessive.
  • the assignment of contact springs to the different circuits is immaterial aside from the fact that the front contacts, with one exception, must all lead to components in the control unit A shown in Figure 1 and the back contacts lead to corresponding components in the control unit B. To avoid unnecessary tracing of circuits the connections between the back contacts and control unit B have not been shown.
  • relays EM, 602 and 603 being unenergized. Control may be switched to control unit A by momentarily closing switch I09A on that unit. This energizes relays 60I and 602, the circuit for which may be traced from the +L terminal at switch I01 in station A through one of the conductors 80 or BI, switch I01 at station B, conductor 9, switch I09A (momentarily closed), conductor 48, contacts and b of relay 604, conductor 80 and through the coils of relays SM and 602 to the L terminal.
  • the relay circuit just traced is locked up by closure of contact e and its front contact on relay 602, this locking circuit extending temporarily (until the hand-set I02 is lifted from its hook) from live conductor 9 to conductor I9, thence through contacts of switch I09B, and conductor 80 to the coils of relays SM and 602.
  • control unit A for the period of a telephone conversation may be insured by lifting the hand-set thereat.
  • This energizes the lock-out relay 604 in the following manner: Live conductor 9 connects through contact d of relay 602 to conductor 36, thence through contacts g and f of switch hook IOI, conductor 46, contact 0 of relay 602 and the coil of relay 604 to the L terminal.
  • This circuit is also branched to the starter terminal 209 so that the motor generator may be started up for supplying power to the transmitter.
  • relay 604 Closure of its contacts e and d makes direct connection between the +L terminal and conductor 9, and since relays 602 and 604 are both energized the +L potential traverses contacte of relay 602, conductor 19, contacts a and b of relay 604 and conductor 80 to the coils of relays GM and 602. Note that contacts a and b of relay 604 are in shunt with switch I09B in control unit B, so that the opening of that switch cannot result in loss of control at the control unit A so long as its hook-switch is up. Furthermore, the switches I01 are effectively shunted by contacts d and e on relay 604, thus preventing the power from being shut off at the unused control unit.
  • control unit B When control unit B is to be used, the operator will first see that the power switch I01 iscorrectly set for lighting the Power on pilot lamp I08. If no sound is heard in his speaker he operates switch I09B momentarily in order to break the locking circuit that held relays SM and 602 energized by previous use of control unit A. Control. is then returned to control unit B, provided the operator at control unit A has hung Now the lifting of the hand-set at control unit B results in energizing the look-out relay 604 through circuits which are like those previously described in reference to control unit A, but which traverse the back contacts associated with movable contacts d and c on relay 602. Note that contact 0 of relay 604 is connected through conductor48 to a contact of switch 109A at control 10 unit A.
  • Closure ofswitch-hook contacts i and g causes a restoring voltage to :be applied to the stepping magnet (not shown) in the code selector, whereby the code wheel is restored to normal and the ringing of the bell 404 ceases.
  • the channel selector should be turned to the desired channel number and the'volume control adjusted to a satisfactory level either for loud speaker use or ear-phone use.
  • the calling procedure is relatively simple:
  • the channel selector switch should also be turned to stand-by (0) position and the receiver volume adjusted to a sufficiently high level so that the next incoming call will be clearly heard on the loud speaker.
  • radio frequency channels For service in the Mississippi River region the radio frequency channels atpresent assigned and their uses are as follows:
  • a multiple-position gang switch the wipers of which have a stand-by position and to any position corresponding to a selected communication channel, and, connected thereto, a plurality of receiving units each differently tuned to one of the channel frequencies to be used, a selective ringer responsive to code signals when received on certain of said channels, an audible responsive device, a volume regulator and gain control circuits individual to certain amplifier stages in each of said receiving units, said gang switch being operable in a stand-by position: (1) to connect a number of said gain control circuits through said volume regulator to the corresponding amplifier stages, (2) to connect the corresponding receiving units to said audible responsive device, and '(3) to connect the remaining Frequency 2206 2738 To communicate with New Orleans only. Ship to Ship Various Shore Stations.
  • a multiple-position gang switch the wipers of which have selected positions each corresponding to a selected communication channel, a plurality of receiving units each having one amplifier stage and each differently tuned to one of the channel frequencies to be used, an audible responsive device, volume regulators, and gain control circuits one of each corresponding to one amplifier stage in each of said receiving units, said gang switch being 'connected to said amplifier stages, said response device, and said volume regulators and gain control circuits, said gang switch being operable: (l) to the channel frequencies to be used, a selective ringer responsive to code signals when received on certain of said channels, an audible responsive device, a volume regulator and gain control circuits individual to certain amplifier stages in each of said receiving units, said gang switch being operable in certain of its channel selecting positions: (1) to connect the gain control circuit to the selected receiving unit through said volume regulator; (2) to connect the same receiving unit to said audible responsive device; (3) to disconnect the gain control circuits of certain others of said receiving
  • a multiple position gang switch the wipers of which have different selective positions corresponding to selected radio frequency channels, including "certain channels in a high frequency band and other channels in a low frequency band, an audible responsive device, a selective ringer, a plurality of receivers, adjustable gain control circuits each corresponding to certain amplifier stages in each of said plurality of receivers, said receivers being individually tuned to different ones of saiclchannels and thereby including low frequency and high frequency receivers each having output terminals and circuit means connected to the wipers and stationary contacts of said gang switch and also connected to: (a) said responsive device, (In) said ringer, (G) the adjustable portions of said gain control circuit arrangement, and (d) the output terminals of said receivers, said means being operable in accordance with the setting of said switch wipers: (1) to connect the output terminals of said low frequency receivers to said audible responsive device, (2) to connect the gain control circuit to the selected receiver, (3) to disconnect
  • a multiple position gang switch the wipers of which have different selective positions corresponding to selected radio frequency channels including certain channels in a high frequency band and other channels in a band of relatively low frequency, an audible responsive device, a selective ringer, adjustable gain control circuits individual to certain amplifier stages in each of a plurality of receivers, said receivers being individually tuned to different ones of said channels and thereby including low frequency and high frequency receivers each having output terminals, and circuit means connected to A the wipers and stationary contacts of said gang switch and also connected to said responsive device, said ringer, the adjustable portions of said gain control circuits, and the output terminals of said receivers, said means being operable in accordance with the setting of the switch wipers:
  • a multiple position gang switch the wipers of which have selectively difierent positions corresponding to selected radio frequency channels including certain channels in a high frequency band and other channels in a band of relatively low frequency, and, connected to said switch, an audible responsive device, a selective ringer, adjustable gain control circuits individual to certain amplifier stages in each of a plurality of receivers, said receivers being individually tuned to diiferent ones of said channels and thereby including low frequency and high frequency receivers each having output terminals, and circuit means connected to the wipers and stationary contacts of said gang switch and also connected to said responsive device, said ringer, the adjustable portions of said gain control circuits, and the output terminals nel selectorswitch for usein a radio telephone system, said switch comprising a plurality of contact wafers each having a movable contact wiper and an.
  • the corresponding gain control circuit is connected to the selected each comprising a hand-set, a channel selector switch to selectively choose one of said circuits when connected to said transmitter receiver, and remote-control switching means, and a junction box containing relays connected to and subject to control from said remote control units, said remote control switching means being connected to said circuits,- said hand-set, and said channel selector switch and operable: (1) to connect the channel selector switch at a particular one of said control units to said transmitter receiver, and (2) to actuate at least two of the relays in 7 said junction box, thereby to cause the other control unit to be disconnected from the receiver.
  • a transmitterreceiver installation comprising pre-tuned radio frequency circuits for selective use on a plurality of different channels, a motor-generator for energizing the circuits of the transmitter, a direct current source for energizing the receiver circuits and for driving said motor-generator, two remote control units each comprising a hand-set, a channel selector switch and remote control switching means, and a junction box containing relays subject to control from one of said control units whereat control is'preempted, said remote control'switching means being operable: 1) to coin nect the direct current source to said generator and to-connect said direct current source to said receiver circuits, (2) to connect said pre-tuned circuits to the channel selector switch at the prempting control unit, and (3) to actuate at least two of the relays in said junction box, thereby to cause the unused control unit to be disconnected frequency channels in one housing and two control units remotely situated with respect toeach other and to said housing, audible
  • a radio telephone system comprising a remote control unit and transmitting and receiving apparatus including components thereof which are pre-tuned for operation on different radio frequency channels, said apparatus bein separately housed with respect to said remote control unit, a manually operable gang switch in said control unit, said switch having a standby position connecting aplurality of components simultaneously in circuit in said receiving apparatus for elfecting multiple channel monitoring of incoming signals by said receiving apparatus, and having single channel selecting positions connecting selected components in circuit in said apparatus for obtaining single channel operation of the transmitting and receiving apparatus, a motor-driven gang switch in the housing of said transmitting and receiving apparatus, electrical means for causing the motor-driven gang switch to assume any one of a plurality of single channel positions corresponding to that to which the manually operable gang switch is concurrently set, said motor-driven gang switch constituting means connecting a single selected component in circuit in said transmitting apparatus for causing said transmitting apparatus to be tuned to a desired channel frequency corresponding to the selected receiver frequency, means connected to the manual gang switch and operable by selective
  • a radio telephone system comprising a re- 16.. mote control unit and receiving apparatus including components thereof which are pre-tuned for operation on different radio frequency channels, said apparatus being separately housed with respect to said remote control unit, a manually operable gang switch in said control unit, said switch havin a stand-by position to connect a plurality of components in said apparatus for efiecting multiple channel monitoring of incoming signals by said receiving apparatus, and having other positions to connect a selected component in said apparatus to provide reception on a selected radio frequency channel, output circuits and gain control circuits for each of said differcntly tuned receiving apparatus components, said output and gain control circuits having connections completed by said manually operable gang switch in selected positions thereof whereby said apparatus effectively receives single channel voice reception and the concurrent reception of incoming selective code signals by others of said receiving apparatus components.
  • a radio telephone system comprising transmitting and receiving apparatus arranged for two-way service on any one of a plurality of radio frequency channels and having means for monitoring simultaneously a plurality of channels for incoming signals, a pair of remote control units each including a microphone-earphone hand-set, and control switches for establishing different circuit conditions in said system, a push-button on each hand-set, relay means subject to control by said push-button for conditionin said transmitting apparatus to radiate a signal modulated by a microphone of a selected hand-set, said relay means being at the same time effective for silencing the receiving apparatus, other relay means automatically operable to disconnect the other control unit until the hand-set which is in service is hung up, and channel selecting means operable at times to condition the transmitting and receiving apparatus for single channel twoway communication and at other times for multiple channel monitoring of incoming signals.
  • a system including a selective ringer and a loud speaker, circuits to connect certain channel-tuned units of said receiving apparatus and said loud speaker, other circuits to connect the ringer with the remaining units of said receiving apparatus; said channel selecting means being effective to make all of said circuit connections, and means for controlling the volume of response in. the loud speaker.

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  • Computer Networks & Wireless Communication (AREA)
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US686265A 1946-07-26 1946-07-26 Radiotelephone equipment Expired - Lifetime US2458558A (en)

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FR948180D FR948180A (GUID-C5D7CC26-194C-43D0-91A1-9AE8C70A9BFF.html) 1946-07-26
US686265A US2458558A (en) 1946-07-26 1946-07-26 Radiotelephone equipment

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US686265A US2458558A (en) 1946-07-26 1946-07-26 Radiotelephone equipment

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Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2515561A (en) * 1948-06-21 1950-07-18 Frank M Lindley Communication mechanism
US2533662A (en) * 1947-04-11 1950-12-12 Automatic Elect Lab Automatic trunk selecting system for radio telephone stations
US2545894A (en) * 1947-05-09 1951-03-20 Bessie S Parker Noninterceptive radio communication system
US2599904A (en) * 1948-09-15 1952-06-10 Times Facsimile Corp Multistation selective communication system
US2641757A (en) * 1950-05-17 1953-06-09 Bell Telephone Labor Inc Automatic multichannel selection
US2649540A (en) * 1946-07-08 1953-08-18 John H Homrighous Multiplex radiophone communication system
US2686257A (en) * 1950-03-15 1954-08-10 Bell Telephone Labor Inc Radio telephone communication station
US2693526A (en) * 1949-06-15 1954-11-02 Automatic Elect Lab Single channel single frequency mobile radio telephone system
US2796574A (en) * 1953-06-04 1957-06-18 Bendix Aviat Corp Re-entrant switching servo system
US4048561A (en) * 1975-11-28 1977-09-13 Robyn International, Inc. Apparatus for preventing simultaneous transmission and channel selection in a transmitter or transceiver
US4396802A (en) * 1981-05-28 1983-08-02 The United States Of America As Represented By The Secretary Of The Navy Aswixs remote speaker and handset set
US4864564A (en) * 1986-06-30 1989-09-05 U.S. Philips Corporation Packet radio

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB311450A (en) * 1928-02-11 1929-05-13 Sidney Richardson Improvements in the employment of wireless apparatus
US2064905A (en) * 1934-05-26 1936-12-22 American Telephone & Telegraph Common medium multichannel exchange system
US2093847A (en) * 1936-05-19 1937-09-21 Bell Telephone Labor Inc Radio telephone monitoring system
US2137023A (en) * 1935-12-20 1938-11-15 Bell Telephone Labor Inc Carrier communicating system
US2164950A (en) * 1937-10-20 1939-07-04 Du Pont Process for forming agglomerates
US2176868A (en) * 1937-03-15 1939-10-24 Lorain Telephone Company Radio communication system
US2265056A (en) * 1940-09-27 1941-12-02 American Telephone & Telegraph Radio telephone system
US2399738A (en) * 1944-03-29 1946-05-07 Gen Railway Signal Co Centralized traffic controlling system for railroads
US2419593A (en) * 1944-06-29 1947-04-29 Rca Corp Two-way radio communication system

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB311450A (en) * 1928-02-11 1929-05-13 Sidney Richardson Improvements in the employment of wireless apparatus
US2064905A (en) * 1934-05-26 1936-12-22 American Telephone & Telegraph Common medium multichannel exchange system
US2137023A (en) * 1935-12-20 1938-11-15 Bell Telephone Labor Inc Carrier communicating system
US2093847A (en) * 1936-05-19 1937-09-21 Bell Telephone Labor Inc Radio telephone monitoring system
US2176868A (en) * 1937-03-15 1939-10-24 Lorain Telephone Company Radio communication system
US2164950A (en) * 1937-10-20 1939-07-04 Du Pont Process for forming agglomerates
US2265056A (en) * 1940-09-27 1941-12-02 American Telephone & Telegraph Radio telephone system
US2399738A (en) * 1944-03-29 1946-05-07 Gen Railway Signal Co Centralized traffic controlling system for railroads
US2419593A (en) * 1944-06-29 1947-04-29 Rca Corp Two-way radio communication system

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2649540A (en) * 1946-07-08 1953-08-18 John H Homrighous Multiplex radiophone communication system
US2533662A (en) * 1947-04-11 1950-12-12 Automatic Elect Lab Automatic trunk selecting system for radio telephone stations
US2545894A (en) * 1947-05-09 1951-03-20 Bessie S Parker Noninterceptive radio communication system
US2515561A (en) * 1948-06-21 1950-07-18 Frank M Lindley Communication mechanism
US2599904A (en) * 1948-09-15 1952-06-10 Times Facsimile Corp Multistation selective communication system
US2693526A (en) * 1949-06-15 1954-11-02 Automatic Elect Lab Single channel single frequency mobile radio telephone system
US2686257A (en) * 1950-03-15 1954-08-10 Bell Telephone Labor Inc Radio telephone communication station
US2641757A (en) * 1950-05-17 1953-06-09 Bell Telephone Labor Inc Automatic multichannel selection
US2796574A (en) * 1953-06-04 1957-06-18 Bendix Aviat Corp Re-entrant switching servo system
US4048561A (en) * 1975-11-28 1977-09-13 Robyn International, Inc. Apparatus for preventing simultaneous transmission and channel selection in a transmitter or transceiver
US4396802A (en) * 1981-05-28 1983-08-02 The United States Of America As Represented By The Secretary Of The Navy Aswixs remote speaker and handset set
US4864564A (en) * 1986-06-30 1989-09-05 U.S. Philips Corporation Packet radio

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