US1833986A - Radio tuning means - Google Patents

Radio tuning means Download PDF

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US1833986A
US1833986A US302233A US30223328A US1833986A US 1833986 A US1833986 A US 1833986A US 302233 A US302233 A US 302233A US 30223328 A US30223328 A US 30223328A US 1833986 A US1833986 A US 1833986A
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tuning
elements
variable
adjustable
circuit
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John J Christoffel
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    • HELECTRICITY
    • H03ELECTRONIC CIRCUITRY
    • H03JTUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J5/00Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
    • H03J5/24Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection
    • H03J5/26Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection operated by hand
    • H03J5/32Stationary tuning circuits or elements selected by push-button

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  • a further object is toV provide an improved radio receiver which is relatively cheap to manufacture and having ⁇ simple tuningy elements which may be used in place of the ordinary .tuning elements for conveniently tuning said receiver to predetermined broadcasting stations.
  • a further object is to provide van improved radio receiver having the usual variable tuning elements" andsupplementary relatively simple yadjustable 'tuning velements which upon the actuation of simple switching mech- A anism may be selectably used instead of said usual variable ⁇ tuning elementsl-
  • a further object, supplementing the object y last above mentioned, is to provideswitching mechanism whereby eachy of said simple adj be adjusted j thrown downwardly ⁇ fromf the positions justable tuning elements mayv independently of the other simple adjusting tuning elements, whereby the matter of adjustment is simplified.
  • I receiver involves two tuning elements; land A Figure 2 shows ancembodimentvof the present invention applied to a circuit of Figure l illustrates an embodiment of the I' ling inductance l or 2.
  • the present invention contemplates means for vselectably removing from circuit theusual ⁇ tuning ele- .65 ments of a radio receiver and inserting into circuit certain simple adjustable tuning'elements, which simple adjustable tuning elements may be set at predeterminedvalues.
  • the numerals 1 and U 2 indicate inductances and the numerals 3 Vand l indicate tuning condensers forming part of the two tuning units cfa radio receiver,
  • the connections/of saidcondensers 3' and A; to ⁇ the inductances l and 2, respectively, are controlled bythe doublepoledouble throw switches 5- 5, preferably connected to operate in unison.V ⁇ Wheii ⁇ the double pole double throw switches 5-5 arein positionto connect the variable condensers '8 an'd'i to the inductances l and 2, respectively, the radio receiver will be connectedfor itsusiial operation.
  • the numerals 6-6 indicate v an Yauxiliary circuit adapted to be connected tothe in'ductaiice l, andthe numerals 7-7.-55 j .indicate an auxiliary circuit adapted ⁇ to be,
  • the rvariable condenser 4 ⁇ may still be maintained in cooperativerela- Y circuit 7 7 are a plurality of simple adjustable condensers 10-10, each of which is controlled by a corresponding switch 11.
  • Each switch 9 will preferably be connected to opcrateY simultaneously with a corresponding s vitch 11, whereby' the operator, with a single movement, may close the circuit through predetermined sets of adjustable condensers' 8-10.
  • variable condenser 4 With lsaid variable condenser 4 in position for timing in a predetermined broadcasting station, one of the adjustable -condensers 8V will lbe manipulated until said broad-v casting station is'ltuned in'. With the tuning condenser 4 set for different' broadcasting e5vr station,another yof the adjustable condensers 8 will be set forsaid other station.k ⁇ A
  • F igurel 2 illustrates the A present invention asy applied 'to ⁇ aradio receiver v'having three tuning elements.
  • Y The features yrelating 'to the present invention will be clear fromthe description of' Figure 1, the features relating to the present 'invention added in ' Figure2 *being the same as those associated with the inductance2 in Figure 1, said added'features having similar reference numerals to.- ⁇ correc sponding parts in Figure 1, but withv the4 letter A added thereto. rlhe inductances in Figure 2 are indicated bythe numerals 1,
  • all of the adjust-able con-v densers 8 are set for predetermined broadcasting stations. After all of the variable condensers 8-8-8 have been set for difierent broadcasting stations, the double pole double throw switch 12 will be thrown to connect th-e circuit 7-7 in cooperative relationship with the inductance 2, the switch 12A ⁇ being left in position to connect the variable condenser 4A and the inductance 2A.
  • the radio receiver may be operated in the ordinary manner, if preferred, by merely throwing the doublepole double throw switches 5-5 to their upper positions as the parts are viewed in Figures 1 and 2.
  • the operator of the set may, after the adjustable condensers 8 8-8, 10-#10-40 and 10A-1OA-#10A have once been adjusted, with a simple movement simultaneously operate a predetermined set of switches 9, 11 and 11A, whereby the corre'- sponding condensers 8, 10 and 10A are in circuit to tune in a predetermined broadcasting station. Similar operation of other sets of switches 9, 11 and 11A will connect in circuit other sets of condensers 8, 10 and 10A to bring in other broadcasting stations.
  • a radio receiver In a radio receiver, a pluralityof'variable tuning elements forV tuning in any preferred requencywithin the Vlimits of said receiver, a plurality ofadjustable tuning elements'associatedwith each 'of said .variable tuning elements, switchl'means ⁇ for vsubstitutvariable tuning elements, each ⁇ ofsaid auX- iliary-switch means being adaptedto render operative its corresponding 'variable' tuning ⁇ element regardless of theoperation of' saidV 3,
  • a radio-receiver a plurality of Vari-v able tuning elements, circuitsassociated with said variabletuning elements, ⁇ each of said v circuits containing a pluralityof adjustable v tuninggeleinents, switch means operable in Y unison for selectably rendering operative said l.
  • variable tuning elements or their corresponding circuits - and means for rendering operative certain of said variable tuning elements V regardless of the connections of said otherv variable tuning elements in circuit for permitting the adjustment of the adjustable tun- V ing elements in each of said circuits independently of the other variable tuning ele- '40 'ments hor vthe 'other adjustable jtuning elenrients,A each of said circuits being provided l with a pluralityv of switches -for selectably connecting saidV adjustable tuningelements ⁇ into operative relationship Y with Vsaid circuit, corresponding switches in said-circuits being connected to operate inunison.
  • Q Y a pluralityv of switches -for selectably connecting saidV adjustable tuningelements ⁇ into operative relationship Y with Vsaid circuit, corresponding switches in said-circuits being connected to operate inunison.

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  • Channel Selection Circuits, Automatic Tuning Circuits (AREA)

Description

`. 1, 1931. .1.J. cHRls-rol-'FEL RADIO TUNING MEANS Filed Aug. 27, 192e 2 Sheets-Sheet l Dec- 1, 1931- J. .J. cr-llalsToFr--EL 1,833,986
RADIO TUNING MEANSv Filed Aug. 2v, 1928 2 sheets-shed 2 Patented Dec. l, 1931v UNITE-D STATES .PATENT OFFICE f JOHN .r`.`cHR1sToFfFnL, or cin-CAGO, ILLINOISI limpio TUNiNGjMnANs applicati@ mea Augusta?,192e.1 serial Naoazaa f `A further object is to provide aniniproved radio receiver havingthe advantage that the operator may at will tune either by means of the usual tuning units or by means of tuiiing elements selectably responsive .to simple switching mechanisms." j
A further object is toV provide an improved radio receiver which is relatively cheap to manufacture and having `simple tuningy elements which may be used in place of the ordinary .tuning elements for conveniently tuning said receiver to predetermined broadcasting stations.
A further object is to provide van improved radio receiver having the usual variable tuning elements" andsupplementary relatively simple yadjustable 'tuning velements which upon the actuation of simple switching mech- A anism may be selectably used instead of said usual variable `tuning elementsl- A further object, supplementing the object y last above mentioned, is to provideswitching mechanism whereby eachy of said simple adj be adjusted j thrown downwardly `fromf the positions justable tuning elements mayv independently of the other simple adjusting tuning elements, whereby the matter of adjustment is simplified. i y
Further objects will appear as thedescription proceeds. Y
Referring to the drawingsi I receiver involves two tuning elements; land A Figure 2 shows ancembodimentvof the present invention applied to a circuit of Figure l illustrates an embodiment of the I' ling inductance l or 2.
usual design `having three tuning elements j Therev is a need at the lpresent time for a-V radio receiverwhich willA permit the. tuning in of a limited lnumber of predetermined yjbroadcasting stations merely by operation lor 55 abutton,lever,`or equivalentelement. It lbeen suggested thatfa simple lever' mecha-l nism be provided for positively .movingfthe tuning elements of a radioreceiverto 'pre-` determined" positions for timing in certain Q0 predetermined broadcasting stations. j l i The present invention diiers from; the idea Y `immediately above referred to. The present invention contemplates means for vselectably removing from circuit theusual` tuning ele- .65 ments of a radio receiver and inserting into circuit certain simple adjustable tuning'elements, which simple adjustable tuning elements may be set at predeterminedvalues.
` Referringto Figure 1, the numerals 1 and U 2 indicate inductances and the numerals 3 Vand l indicate tuning condensers forming part of the two tuning units cfa radio receiver, The connections/of saidcondensers 3' and A; to `the inductances l and 2, respectively, are controlled bythe doublepoledouble throw switches 5- 5, preferably connected to operate in unison.V `Wheii` the double pole double throw switches 5-5 arein positionto connect the variable condensers '8 an'd'i to the inductances l and 2, respectively, the radio receiver will be connectedfor itsusiial operation. The numerals 6-6 indicate v an Yauxiliary circuit adapted to be connected tothe in'ductaiice l, andthe numerals 7-7.-55 j .indicate an auxiliary circuit adapted `to be,
`connected to the inductance 2.. When the doublevpole double throw switches 5-5 are! hown in Figure l, the correspondingvari- 4' will be thrown out l able` condensers 3 and "of cooperativerelationship withfthe corre-W sponding inductances j 1 and 2, and circuits 6-6 and circuit 7 -7 will be thrown into c0- operative relationsliip with the correspond- Connected in parallel across thefcircuit 6-.-6 are a plurality o sinipleadjustablecondensers' 8-8, each of which is controlled by a switch9. Similarly connected across thenl 59 pole throw.A switch 5, the rvariable condenser 4`may still be maintained in cooperativerela- Y circuit 7 7 are a plurality of simple adjustable condensers 10-10, each of which is controlled by a corresponding switch 11. Each switch 9 will preferably be connected to opcrateY simultaneously with a corresponding s vitch 11, whereby' the operator, with a single movement, may close the circuit through predetermined sets of adjustable condensers' 8-10. YIt will be readily understoodgthat by opening the double pole double throw switches -5 and by closing the condenser fswitches 9 and 11, one ycondenser 8.(,which will have been set to a predetermined value) will ce substituted for the Vvariable condenser i 3,` and one condenser 10 A(which will `have been set to a predetermined value) will/be substitutedfor the variable condenser 4.
'lhesimple adjustable condensers 8-8-8 i f. and'10-10-10 vneed Vonly be relatively inexpensive, and foiythis purpose it-is'p'referred touse the .typekn'own as semi-fixed, which type {is characterized by the fact that'the value of the condenser may be adjusted by 'the simplel manipulation of va `screw or the like( (For purposes of econcmy of manufacture, therefore, itis preferred not to 4have Vthe condensers 8-8'-8 anc iO-lO-lO of anc expensive typeV having indicating means for accurately'indicating their capacities. An
inexpensive Ameans for conveniently setting theV adjustable,condenseis 8 8-8 and 10-l 10-10 is illustrated in the set-up associated with theinductance 2. By reference to Figure l it will be noted that the connection of the circuit 7-7 with itsv double pole double throw switch 5 is controlled by the doublel pole double throw switch 12,' which double pole vdouble throw switch 12 is shown in position to connectsaid circuit 7 7 to its double pole double throw'switch 5. The nu- ;merals 13-13 indicate a circuit cooperating with the double pole double throw switch 12and the corresponding double pole double .throw switch 5.- As' indicated above, the switches '5f-45 ,are preferablyfconnected to movein unison. When the variable-condenser 3 is thrown 4out of cooperative relationshipf'withr theA inductance 1 by reason of movement of the corresponding double tionship with 'the inductancer 2 by manipuv lation of a double pole" double throw switch 12. ,'Whenf'tlie double pole double throw switch 5 Ycooperatively associated withfthe inductance 2 is in its lowermost position as theyparts are viewed in igure 1, said; inductance :may be connected to the variable condenser 4 by moving thcidouble pole double throw' switch 12 to the'V right as the parts are ,viewed in Figure l, or, said in'ductancef2` may be connected to the circuit 7-7 by moving said double pole double throw switch 12 to the left the parts are viewed in Figi and thedouble pole double throw switch 12 will be moved toward the right `-1as the parts are viewed in vFigure 1. Under these conditions the adjustablejcondensers 8-8-8 will be in cooperative'relationship `with inductance 1 and variable condenser 4 will be in cooperative relationship with the inductance Y 2. With lsaid variable condenser 4 in position for timing in a predetermined broadcasting station, one of the adjustable -condensers 8V will lbe manipulated until said broad-v casting station is'ltuned in'. With the tuning condenser 4 set for different' broadcasting e5vr station,another yof the adjustable condensers 8 will be set forsaid other station.k `A
plurality ofbroadcasting stations 'may be accommodated, depending uponthe number'of .lO-lOlO, lAftery the adjustablecondens- Vers 8-18-'8 have all been setfor predetermined broadcasting' stations, the double pole double throw switch v12 will be moved to its left-hand positionasthe parts arel 'shown in Figure 1, throwing the `'variable condenser 4 out of circuit and throwing the circuit 7 '7 into cooperative relationshipwith inductance f 2.v `With one of the adjustable oon'densers "8 in circuit, aYcorresponding:condenser` 10 will be set to bring in the corresponding broadcasting station.y A .similar procedure 'will be carried out with 'each'fof the'other adjustable condensers 8 and their corresponding adjustable condensersj10,until all'v of the sets of adjustable condensers y'8;10 have ybeen 'i `brought into proper'tuning relationship with different broadcasting stations. j.
Figure 1 shows the vpresent invention as applied to a radio receiver having two tun-` ing elements. kAssociated partsof areceiver have been indicated generally by the numeral 14, but inasmuch as said associated parts form nopart ofthe present inventiony a description thereofis deemed tobeunneces'sary.
F igurel 2 illustrates the A present invention asy applied 'to` aradio receiver v'having three tuning elements. Y The features yrelating 'to the present invention will be clear fromthe description of'Figure 1, the features relating to the present 'invention added in 'Figure2 *being the same as those associated with the inductance2 in Figure 1, said added'features having similar reference numerals to.-` correc sponding parts in Figure 1, but withv the4 letter A added thereto. rlhe inductances in Figure 2 are indicated bythe numerals 1,
2 and 2A, and the correspondingcondensers are indicated by the numerals ,3, 4 andi`4A. In Figure' 2 the double pole double'throw switches'5-5`5 are lpreferably connected to operatev in unison. The double pole double throw switches 12 and 12A, however, will preferably be independently operable, whereby it will not be necessary to attempt toadjiist simultaneously the adjustable condensers associated with two of the tuning elements. The associated .parts of the three tuner circuit illustrated in Figure 2 have been indicated by the numeral 15.
As will be understood from the discussion of Figure 1 appearing above, a predetermined broadcasting station may be tuned in by manipulation of the three variable condensers 3, 4 and 4A, after which the `.double pole double throw switches 5-5-5 may be thrown downwardly. One of the adjustable condensers 8 will then be adjusted to tune in said predetermined broadcasting station. In
similar manner, all of the adjust-able con-v densers 8 are set for predetermined broadcasting stations. After all of the variable condensers 8-8-8 have been set for difierent broadcasting stations, the double pole double throw switch 12 will be thrown to connect th-e circuit 7-7 in cooperative relationship with the inductance 2, the switch 12A` being left in position to connect the variable condenser 4A and the inductance 2A. Each of the adjustable condensers 10.-
10-10 will then be adjusted to time in the same stations for which the corresponding condensers 8 8-8 were set. Thereafter, the double pole Vdouble throw switch 12A will be moved to position to connect the circuit 7A-7A to the inductance 2A, afterl which the adjustable condensers 10A-10A- 10A will be adjusted to tune in the same stations to which the corresponding condensers 8-8-8 and 10-10-10 have been adjusted.
It will be clear that the radio receiver may be operated in the ordinary manner, if preferred, by merely throwing the doublepole double throw switches 5-5 to their upper positions as the parts are viewed in Figures 1 and 2. VIf the convenience of the predetermined settings is desired, the operator of the set may, after the adjustable condensers 8 8-8, 10-#10-40 and 10A-1OA-#10A have once been adjusted, with a simple movement simultaneously operate a predetermined set of switches 9, 11 and 11A, whereby the corre'- sponding condensers 8, 10 and 10A are in circuit to tune in a predetermined broadcasting station. Similar operation of other sets of switches 9, 11 and 11A will connect in circuit other sets of condensers 8, 10 and 10A to bring in other broadcasting stations.
Many modifications of the present invention will occur to those skilled in the art. It is intended to cover all such modifications thatfall within the scope of the appended claims.
What is claimed is- 1. In a radio receiver, a plurality of variable tiining elements, circuits associated with said variable tuning'eleinents,'each of' said `circuits containing a plurality of, adjustable timing elements, switch means operable Ain unison for selectably rendering operativesaid variable timing elements or their lcorrespondling circuits, and meansfjor rendering operativecertain yof said'V variable tuning elements regardless of the connections of said other variable timing elements in circuit for'permittingthe adjustment of the adj ustabletunf ing elements in eachjof said circuits inde'- pendently of the other variable' tuning'ele-g inents or theother adjustable timing elements.
y v V2. In a radio receiver, a pluralityof'variable tuning elements forV tuning in any preferred requencywithin the Vlimits of said receiver, a plurality ofadjustable tuning elements'associatedwith each 'of said .variable tuning elements, switchl'means `for vsubstitutvariable tuning elements, each` ofsaid auX- iliary-switch means being adaptedto render operative its corresponding 'variable' tuning `element regardless of theoperation of' saidV 3, In a radio receiver, a` plurality of iii-y Y ductances, avariable tiiningelement coopera` tively associated with each of said inductances, a plurality of circuits,reach cooperativelyassociated with! a 'corresponding onefot` .said inductances, switch means cooperatively associated with each vof said inducta'nces, said switch means being operable in-'unisonfor selectively controlling'the connection of said indiictances to 'said variable tuning elements or to said circuits, eachof` said circuits-in-N `cliiding a plurality of adjustable tuning-ele# ments, said adjustable tuning'elementsbeing ico i Aadaptedl to be thrown into or out of circuit in sets CorrespendingV tofsaidvariable tuning elements, and switch means associatedwith one fof j said inductances V:for connecting said inductance to its correspondingvariabletuningelement regardless offthe operation of said first mentioned switch means and re` gardless'fofthe operation in setsofsaid adj ustable tuning elements. j
4. In a radio receiver, apliirality of variable tiining elements, a plurality of circuits each containing a plurality ofadjustable tuning elements, said circuits being adapted to` replace said variable' tuningqelementsin the operation of said receiver, switch means for selectably rendering operative said variable tuning elements or said circuits,'and other switch means cooperatively associated with one of said variable tuning'elements for conf" trolling the operativeness ofV its corresponding variable timing element regardless of the `operativeness of any of the other of said variable tuning elements,each of said circuits being provided with a plurality of switches VYfor selectabrly connecting said adjustable tuningr elements into operative relationship with saidcircuit, corresponding switches in said circuits being connected to operate in unison. 5. In a radio` receiver,'a'plurality of variable, tuning elements, a plurality of circuits each containing a plurality of adjustable tuning elements, said circuits being adaptedto replace said Variable tuning elements in the` i operation of said receiver, switch means for substituting s'aid circuits for said yVariable tuning elements in the control of' said receiver, and switch means cooperatively associated with certainvof said variable tuning V elements for controlling the operativeness of its corresponding variable tuning element regardless of the operativeness of any of-said other tuning elements or said adjustable tunj ing.y elements associated; with said otherl tun- .ing elements, each of 'said' circuits being proy vided with a plurality of switches .for selectL Y ably connecting said adjustable tuning elements into operative relationship with said circuit, corresponding switches in said circuits being connected to voperate in unison.
6. In a radio-receiver, a plurality of Vari-v able tuning elements, circuitsassociated with said variabletuning elements,` each of said v circuits containing a pluralityof adjustable v tuninggeleinents, switch means operable in Y unison for selectably rendering operative said l. variable tuning elements or their corresponding circuits,- and means for rendering operative certain of said variable tuning elements V regardless of the connections of said otherv variable tuning elements in circuit for permitting the adjustment of the adjustable tun- V ing elements in each of said circuits independently of the other variable tuning ele- '40 'ments hor vthe 'other adjustable jtuning elenrients,A each of said circuits being provided l with a pluralityv of switches -for selectably connecting saidV adjustable tuningelements` into operative relationship Y with Vsaid circuit, corresponding switches in said-circuits being connected to operate inunison. Q Y
. Signed at Chicago, Illinois, this'24th day of August; 1928. Y'
` JOHN J. CHRIS'IOFFEL..j`
US302233A 1928-08-27 1928-08-27 Radio tuning means Expired - Lifetime US1833986A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2907876A (en) * 1954-07-15 1959-10-06 Cgs Lab Inc Radio receiver in which signal tuned circuits are controlled by remotely tuned local oscillator
US3009059A (en) * 1959-12-23 1961-11-14 Clell T Stratton Automatic emergency alert system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2907876A (en) * 1954-07-15 1959-10-06 Cgs Lab Inc Radio receiver in which signal tuned circuits are controlled by remotely tuned local oscillator
US3009059A (en) * 1959-12-23 1961-11-14 Clell T Stratton Automatic emergency alert system

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