Патент USA US2114540код для вставки
April 19, 1938. v. c. MACNABB 2,114,540 TUNING MECHANISM FOR RADIO APPARATUS Filed March 8, 1937 v 3 Sheets-Sheet l . 3—* INVENTOR. VEA’Nd/V CI MiG/V1458 BYGZML 4. A,” A TTORNE Y. April 19, 1938. v. c. MACNABB 2,114,540 TUNING MECHANISM FOR RADIO APPARATUS Filed March 8, 1957 5 Sheets-Sheet v2 /4 15 ~ INVENTOR VERNON 6! Mac/V1455 ‘GEM/.4544“, A TTORNEY. April 19, 1938. v_ c, MACNABB . 2,114,540 TUNING MECHANISM FOR RADIO APPARATUS Filed March 8, 1957 3 Sheets-Sheet 3 * INVENTOR. VERA/01v CT Mac/v0.95 BYQMKQAQV ATTORNEY. I 2,1145% Patented Apr. 19, 1938 UNITED STATES PATENT OFFIQE 2,1 14,540 TUNING MECHANISM FOR RAD-IO APPARATUS Vernon C‘. Macnabb, Indianapolis, Ind., assignor to Fairbanks, Morse & 00., Chicago, 111., a cor poration of Illinois Application March 8, 1937, Serial No. 129,639 12 Claims. (Cl. 116—124.1) This invention relates to tuning mechanism for radio apparatus, and more particularly to an im proved tuning dial organization for radios of multiple wave-band type. for these parts in Fig. 4; Fig. 6 is a view in de tail, of a portion of the mechanism shown by Fig. 4; Fig. '7 is a sectional view of a part of the mechanism, as taken along line 'L-‘l in Fig. 4, It has been the general practice heretofore, to ' and Fig. 8 is an elevation shown partly in sec provide in connection with multiple wave-band tion, of the mechanism of Fig. 4, as viewed from radio apparatus, a single tuning dial having thereon tuning indicia for the several bands. One of the disadvantages of such a dial arrangement 10 is that all of the tuning indicia are simultane ously visible, resulting in many instances, in a confusion of wave band indication during tuning. Moreover, where all the indicia for aplurality of wave bands are simultaneously visible, the ar ray of indicia offers of itself a degree of con fusion to the operator. Accordingly‘, it is an. object of the present invention to provide a radio tuning indicator characterized by the selective display of the tuning indicia for but one wave band at a time. Among other objects of the invention are the provision of a tuning indicator for a multi wave band radio having visible only the band in dicia of the particular wave band‘ desired; the pro vision of a tuning indicator having a separate dial member for each wave band, with the dial mem bers relatively displaceable so that only one there of will be visible at any one time, and the provi sion of regulating means for the indicator, adapt ed to operate the several dial members in sequence to obtain the visibility of but one dial member at a time, the regulating means‘being operated preferably by the control element provided for changing the circuit arrangement of the radio “ from one wave-band to another. Further objects and advantages will appear from the description and accompanying draw ings, in which: Fig. 1 is a front elevation of a partly assembled 4 radio chassis, illustrating the improved wave band indicator of this invention; Fig. 2 is a frag mentary plan view of the radio chassis of Fig. 1, showing the front panel of the radio in section, and the disposition of the indicator mechanism relative thereto; Fig. 3 is an enlarged, fragmen tary sectional elevation of the radio chassis and front panel, illustrating certain details of the im proved indicator, the view being taken from line 3-3 in Fig. 1; Fig. 4 is an enlarged side elevation of a part of the indicator, with portions thereof shown in section, as taken along line 4-4 in Fig. 1; Fig. 5 is a front elevation of the device shown by Fig. 5, as viewed from line 5-5 thereon, the View, however, showing certain of the ele 55 ments in an altered position from that indicated line 8-—8 thereon. Referring now to the drawings by suitable nu merals of reference, the improved indicator is operatively associated with the tuning mecha 10 nism of a multi-wave band radio, as will now ap pear. As shown in Figs. 1, 2, and 3, the radio‘ chassis is indicated generally at if], the chassis supporting the radio instruments and apparatus, as for example, a multiple capacity unit of vari able type indicated at H, and a multiple circuit switching device l2 provided for adjusting the apparatus to receive signals in any one of a num ber of different wave bands. The switching de vice I2 is operated by a shaft 13 extending‘ to the front of the radio panel [4, the shaft‘being pro vided with a control handle or knob 15 for manual manipulation thereof. For convenience and simplicity of control, the shaft l3 controlling the shifting of the circuit connections to accommo 25 date the different wave bands, is utilized to regu late the wave band indicator mechanism now to be described.v The panel 14 is provided with an opening 16 of square, circular or other desired con?guration, “ the opening being closed preferably on the back or inner face of the panel, by a transparent mem ber I‘! such as a glass plate. By preference, the glass H is carried by a substantially rigid opaque member or mask 18 formed of either metallic or non-metallic sheet material, the mask it being supported by the chassis H] in any suitable'man ner, as by the bolts l9 and spacer sleeves 20 ex tending between the member and a bracket 28 secured to a side wall 22 of the chassis. Mount ing of the glass H on the mask it may be ef fected in any desired manner, as by the clips 2E3v shown in Fig. 1, As appears in Figs. 2 and 3, the sleeves 20 serve to space the member 18 and glass ll outwardly of the chassis wall 22 so that in the ' assembly relation of the chassis I0 and panel Hi, the glass will seat against the inner side of the panel in a position to close the panel opening l6. Referring to Figs. 1 and 3, the mask I8 is pro vided with a substantially semi-circular opening or window 24 to permit observation of tuning indicia disposed on relatively displaceable dial elements arranged rearwardly of the member 18, as will later appear. In addition, a second slot or Window 25 of smaller extent is formed in the 55 2 2,114,540 member l8, above the slot 24 in the position shown in Fig. 1, this second slot being provided upon a sleeve 39 mounted on a shaft or plunger to permit observation of wave band indicia asso 37, as shown in Fig. 4. As a. means for prevent ing frictional or rubbing contact between adja 4|, the sleeve extending through the extensions ciated with the tuning indicia, as will be presently described. Arranged rearwardly of and in rela tively close adjacence to the member l8, are a plurality of substantially semi-circular dial ele ments, four being shown in the present example, and numbered 26, 2'1, 28, and 29, the element 26 10 being that closest to the member l8. The elements are formed of relatively thin, sheet mate cent dial elements, and also for providing greater rigidity of the elements at the zone of pivotal support, each of the elements is secured in any suitable manner, to a spacer member 42. The dial extensions and spacers are con?ned longi . tudinally of the sleeve, between a shoulder 44 10 formed on one end of the sleeve and a removable rial, such as steel, aluminum or bakelite, and end plate 45 at the opposite end of the sleeve, each is provided with .a portion 39 extended up- ' the plate 45 being retained in assembly by a screw wardly from the mid-section of the semi-circular 15 portion of the element, for a purpose presently to appear. As shown in Figs. 2 and 3, the ele ments are arranged in horizontally spaced rela tion, one in back of another, so that in the posi longitudinal displacement of the sleeve 39 on 15 shaft 4|, the shaft end 40 is formed of reduced diameter, to provide a shoulder 47 against which the shouldered sleeve end 44 seats, in the assem tion shown, only the element 26 will have sur bly of the parts. 20 face portions thereof in register with and ex posed through the slots 24 and 25, respectively. Arranged along that surface of the dial element 26 which is exposed through the slot 24, are tun ing 'graduations 3| and wave length indicia 32. 25 The surface of the extension 39 on element 26 which is exposed through the slot 25, is provided with a suitable indicator of the wave band cor responding to the graduations 3| and wave length indicia 32, this indicator in the present example, 30 being the word “Broadcast”. Each of the re maining elements 21, 28, and 29 is similarly pro vided with an indicator of a particular wave band and indicia of wave length corresponding thereto, although such indicia and, band indi 35 cators are not shown in the present disclosure. It is understood, of course, that the dial elements are associated with a variable tuning device of the radio to indicate the tuning condition there of. In the present example, the tuning device is the variable capacity device or condenser ||. The rotary elements of the condenser are oper ated through the condenser shaft 34, and in the present example the shaft extends toward the radio panel I4, and has a dial hand or pointer 36 45 mounted thereon which plays over the dial face bearing the tuning indicia visible through win dow 24, as. the condenser is operated. As before noted, with the elements 26 through 29 in the positions shown in Figs. 2 and 3, only 50 the tuning indicia and wave band indicator on for a purpose later to appear. The shouldered 25 portion of the bearing member is disposed out wardly of one side of the bracket 2| and adjacent the shouldered end of the dial supporting sleeve 39, as shown in Fig. 4. Formed by preference, as an integral part of the bearing 48 and extend 30 ing through bracket 2|, is a tubular member or cylinder 5|. The shaft 4| extends into the cyl inder 5| and is provided with a head element 54, the peripheral surface of which seats against the internal wall surface of the cylinder, after the 35 manner of a piston. A compression spring 55 is sleeved about the shaft 4|, and con?ned between the shaft head 54 and an internally shouldered part of the cylinder, thus serving to bias the sleeve 39 and dial elements thereon in a direction away 40 from the panel i4. Mechanism of a preferred type now to be de scribed, is provided for controlling both longi tudinal shifting’ of the shaft 4| and hence of the dial elements 26 through 29, and pivotal displace_ 45 .ment of the dial elements for the purpose here tofore noted. The purpose for the longitudinal shifting of the dial elements will appear as the description proceeds. , cator on element 21, the element 26 is adapted in a manner later appearing, tobe displaced suffi tending substantially the length, yet terminating ciently to permit visibility of the tuning indicator element 27 through the slots 24 and 25. Like wise, the element 2'! is displacyeable so as to ex pose the tuning indicia and band indicator on element 28, and similarly the element 28 is dis placeable to expose the indicia on element 29. Since in the present example, the element 29 is the last of the group, it may be retained in its original position and thus will be exposed only when all the other elements have been displaced. 65 Hence, it will be readily observed. from the fore— going, that at any given time, only one of the elements 28 through 29 will be in. position for exposure of its band indicator and tuningiindicia through the windows 24 and 25. 70 The shaft or plunger 4| is journalled for lon gitudinal sliding movement, in a bearing member 48 carried by and extending through a portion of the bracket 2| heretofore noted, said bearing member having an external, rounded shoulder 50 As shown in detail in Figs. 4 through 8, the 50 dial shifting mechanism comprises a substantial ly channel-shaped frame 51 provided with a slot 58 in the bridge portion 59 thereof, the slot ex element 26 .are visible through the slots 24 and 25. To expose the indicia and wave band indi 55 46 threadedly engaging the shaft 4|. To prevent _ V The dial elements 26, 21, and 28 are adapted for sequential displacement, for the purpose above noted, through mechanism now to, be'described. Each of these elements is formedv with a lateral extension 31 terminating in a projection or tail 75 piece 38. The elements are pivotally supported short of the ends of said bridge portion. The sides 55 6| of the frame 57 are substantially triangular in side elevation, as shown in Fig. 4, the edge 62 of each side corresponding to the hypotenuse of the triangle, serving as a camming edge for a purpose presently to appear. In the assembly of 60 the frame to the dial mechanism, the shaft 4| extends through the slot 58, while the solid por tions of the bridge engage the shoulder 44 of the dial carrying sleeve 39. The frame sides 6| straddle the shaft and the camming edges 62 en 65 gage the rounded bearing shoulder 50, in the manner shown in Fig. 4. From the foregoing, it will be observed that the spring 55 acting on the shaft 4 I, and hence on the sleeve 39 serves through these elements to urge the camming edges 62 of 70 the frame against the shoulder 50. As a means for attaining stability of the frame 51 in assembly and during its operation as will be later described, and also, for con?ning the frame to a linear movement of anyextent deter 75 2,114,540 mined by the length of the frame slot 58, there is provided a shaft or plunger 64 spaced from the shaft 4! and longitudinally slidably journalled in a bearing member 65 secured to the bracket 2!, with the shaft extending through the frame slot 58. The shaft 64 is urged in one direction of its slidable movement by a spring 61 sleeved upon the shaft and bearing against the shaft head 68. The spring, shaft, and shaft head are arranged 3 ment only. In operating switch I 2 to change the radio circuit connections, the switch shaft I3 is rotated in steps, the angular extent of rotation thereof in each step being determined by the spacing of the switch contacts (not shown). Ac Cl cordingly, the stepped movement of shaft [3 will effect a corresponding stepped movement of the frame 51, and the extent of linear movement of integral part of the bearing member 65. Thread edly engaging an internal bore in the outer end the frame in each step is correlated with the ex tent of rotary movement of shaft IS in each step 10 so as to attain the desired degree of shifting movement of the dial elements. Such correlation of shaft 64, is a rod ‘H provided for a purpose later to appear, the rod having a. ?ange 12 seat and relation of the elements above described, op 10 within a cylinder 18 which may be formed as an 15 ing against the end of shaft 54 and in engage ment with the bridge portion 59 of the sliding frame 51. The bearing member 65 extends out wardly from bracket 2| a greater distance than does the bearing member 48 heretofore described 20 in connection with shaft 41, and has its exposed end 13 rounded as shown, to provide a bearing seat for the camming edges 62 of frame 51. Thus the frame is con?ned between the end 13 of bear ing member 85 and the ?ange 12 on rod 1|, so 25 that the spring 6'! acting on the shaft 64 and hence on the flange 12, tends to urge the camming edges 62 of the frame against the bearing seat 13. It will be observed from the foregoing descrip tion and from an inspection of Fig. 4, that down 30 ward displacement of the frame 51 from its upper extreme position shown in Fig. 4, will result in an outward shifting of the plungers or shafts 4| and 64, against the pressure of the respective springs 55 and 6? acting thereon, this shifting of the 35 shafts being e?ected by reason of the wedging action of the frame 51 on the said shafts. The provision for the shifting of the shafts, particu larly shaft it i , is made for the purpose of displac ing the assembly of dial elements so that the 40 particular element being disclosed will be close to the window 24 in. panel M. By regulating the actuation of frame 51 to attain a step-by-step movement thereof, the shifting of the dial ele ments may be controlled so that say upon the dis 45 placement of dial element 26, the dial element 21 will be shifted into substantially the spacial posi tion formerly occupied by element 26. Further downward movement of the frame 57 during dis placement of the element 21, will bring the ele 50 ment 28 into the space formerly occupied by ele ment 21, and so for the last element 29. Thus successive movements of the frame in steps, will attain the desired shifting of the elements, and it is to be noted that the results above described 55 will occur in reverse order upon successive up ward movements of the frame 51. Actuation of the frame in a step-by-step man ner, is attained through the operation of the cir cuit changing switch l2 through the control shaft 60 l3. For this purpose, the lower end of the frame 51 is provided with a laterally extending arm having therein a slot 15, the longitudinal axis ‘which is substantially at a right angle to that the frame slot 58. Extending through the slot 14 of of 15 65 is an element or rod 76 having one end thereof secured in any suitable manner, to an actuating arm 19. The arm 19 is operatively secured to the switch control shaft I 3 by a lock screw 82. Thus by rotating the shaft I3, through the handle l5, 70 the frame El will be actuated through the arm ‘i9 and rod 16 in the slot 15 of the frame arm 14. As will be readily understood, the purpose for the slot 15 is to permit movement of the actuat ing rod 16 therealong during rotation of the arm 19, since the frame 51 is con?ned to linear move of movements is effected through proper design eratively connecting the shaft l3 and frame 51. 15 Turning now to the mechanism for effecting successive displacements of the several dial ele ments, this is effected simultaneously with the shifting of the dial elements by the frame 51, through a member 86 secured frame, as by the screws 81. which may be a substantially formed of any suitable rigid to one arm of the 20 The member 86 rectangular plate material, extends outwardly and longitudinally of the frame, being parallel to the arms of the frame, and is pro- - vided with a central aperture or opening 88 of triangular aspect. The marginal portion of the plate aperture, de?ning a side corresponding to the hypotenuse of the triangularly shaped open ing 88, is stepped at 98, 5!, 92, and 93, as shown 3.0 in Fig. 6, with the lower ends of the stepped por tions provided with an outturned lip or ?nger 94, 95, 96, and 91 respectively, as shown in Fig. 5. The lips or fingers on plate 85 are provided for effecting a pivotal displacement of the dial ele 35 ments, in a manner presently to be described. Each of the dial elements is urged to its initial position behind the member i8 and in register with the windows 24 and 25 therein, by a spring 98 having one end secured to the dial extension 40 3'! and its opposite end secured to the rod ‘H on shaft 64. Four such springs are Shown, one for each of the dial elements 28 through 29, although the spring for the last dial element 29 may be omitted, if desired, as this element is normally .45 retained in its original position at all times. The position of the dial elements behind the member I8 so that the tuning indicia thereon will be in register with the windows 24 and 25, is deter mined by a suitable stop element 582 (Figs. 3 and 5) carried by the bracket 2 i. If desired, the stop may be provided by one of the supporting elements for the mask l8, such element being comprised of a bolt !9 and sleeve 28 as hereto fore noted. The stop is provided with an abut 55 ment I83 sleeved thereon, the abutment being formed of any suitable material, such as alumi num or bakelite. Moreover, securing the springs 98 to the rod H on shaft 64 serves to maintain the axis of each spring in the plane of its dial 60 element during shifting of the dial elements by the frame 51, as shaft til supporting the dial ele ments, and shaft 64 supporting rod ‘H are moved an equal distance upon each actuation of the frame 51. 65 The arrangement of the plate 86 on frame 5'! is such that with the plate and frame in the upper most position, as shown in Fig. 4, the dial ele ments will be disposed in their initial position (Figs. 2 and 4) with the tail pieces 38 thereof 70 extending through the lower end of the opening 83 in plate 86 (Figs. 4 and 6). In this position of the several dial elements, the tail piece 38 of dial element 26 is disposed to underlie the actu ating ?nger 94. The tail pieces 38 of the other 75 4 2,114,540 dial elements 21, 28', and 29 are in vertical regis ter but out of engagement with the ?ngers 95, 96, and SH, respectively. Thus upon downward movement of the frame 57 and plate 86, as ef fected by actuation of shaft l3, the ?nger 94 will act upon the tail piece 38 of dial element 26, to pivot the dial element upwardly and out wardly from its initial position behind the win dows 24 and 25, into the position indicated at 10 I05 in Fig. 5. In the displaced position I05 of the element 25, the edge N26 or its extension 31 rests against the plate 85, and the element is retained in such position against the bias of its spring 98, by the ?nger M and surface portion of 15 the plate 86. Simultaneously with the displace ment of dial element 25 and as a result of the downward movement of the frame El’ as hereto fore described, all the dial elements are shifted toward the panel l4 so as to bring the next suc 20 ceeding dial element 2'6 into the space formerly occupied by dial 265, in register with the windows 24 and 25. Successive downward movements of the frame 51 and plate 86 effect in turn, similar positioning of the other dial elements 21 and 28. 25 Actuation of shaft It so as to move frame El and plate 86 upwardly, successively releases the dial elements, in the reverse order of their dis placement, permitting the springs 98 to return At the the elements to their original positions. 30 same time, the dial elements are shifted axially of shaft :1! and in a direction away from the from the vspirit and full scope of the invention, as de?ned by the appended claims. I claimi 1. A tuning dial mechanism of the character described, comprising a plurality of dial elements normally disposed in spaced relation, a member pivotally supporting said dial elements, said member being capable of axial movement to ef fect axial displacement of said elements, and 10 means operatively associated with said dial ele ments and with the supporting member therefor, adapted for effecting concurrently, pivotal and axial displacement of said dial elements. 2. A tuning dial mechanism of the character described, comprising a plurality of dial plates 15 normally disposed in spaced, parallel relation, a member pivotally supporting said plates, said member being capable of axial shifting move ment to e?ect axial displacement of said dial plates, means operable to axially shift said sup 20 porting member and dial elements, and means operated by said shifting means, adapted for pivotally displacing said dial plates. 3. A tuning dial mechanism of the character described, comprising dial elements normally dis- ' posed in spaced relation, means supporting said elements for both pivotal and axial displace ment, and means operatively associated with said dial elements, adapted for effecting pivotal and axial displacement of each of said dial elements. 30 ll. A tuning dial mechanism of the character panel l4, under the action of the camming frame described, comprising dial elements normally dis 51' and springs 55 and 51 acting respectively, on shafts 4i and Ell, so as to return the dials to posed in spaced, parallel relation, means sup porting said elements for both pivotal and axial displacement, and means operatively associated 35 with said dial elements and said supporting 35 their original position rearwardly of the panel. From the foregoing, it will be observed that the mechanism for positioning the tuning dial elements is actuated and controlled by the cir cult changing device for the radio, and the ar 40 rangement is such that upon actuation of the circuit changing device to effect circuit connec tions for reception on a particular wave band. the tuning dial element corresponding to such wave band will be disposed in register with the 45 windows 24 and 25 for visibility of the tuning indicia on such dial. Thus, when the circuit changing device is in position to effect reception on the “Broadcast” band, this being one extreme position of the device, the dial 26 which is the 50 “Broadcast” band dial, will be in position for observance of its tuning indicia through window 24 and band indicator “Broadcast” through win dow 25. When the switch i2 is actuated by shaft l3, through one step to the next succeeding posi 55 tion determining a different circuit connection for reception on another wave band, dial 2? cor responding to such wave band, will be in position for observance of its tuning indicia through win 60 dow 24 and its band indicator through window 25, and similarly for the remaining dial elements. Thus, the present invention provides a tuning indicator mechanism for a multi-wave-band radio, the indicator being characterized by the 65 selective display of tuning indicia for but one wave band at a time. Moreover, the display of tuning indicia corresponding to a given. wave band is made coincidentally with the actuation of the circuit changing device of the radio, to 70 effect the circuit connections for reception on the given wave band. It is to be understood that the invention is not to be limited to the herein described embodi ment thereof, but that alterations and modi?ca 75 tions may be made therein without departing means, adapted for effecting, coincidentally, piv otal and axial displacement of each of said dial elements. 5. In combination with radio apparatus in 40 cluding a tuning device, a panel and an opening in said panel, a tuning dial mechanism compris ing dial plates arranged in spaced, parallel rela tion, means supporting said plates for both piv otal and axial displacement, means biasing said 45 plates to a position in register with said panel opening, and means operatively associated with said dial plates, adapted for effecting a coinci dental pivotal and axial displacement of each of said dial plates out of register with said panel opening. 50 6. In combination with radio apparatus in cluding a tuning device, a circuit changing de vice, a panel and an opening in said panel, a tuning‘ dial mechanism comprising dial elements arranged in spaced, parallel relation, means sup porting said elements for both pivotal and axial displacement, means biasing said elements to a position in register with said panel opening, and means operatively associated with said dial ele ments and actuated by said circuit changing de 60 vice, for effecting sequential displacement of said dial elements out of register with said panel open ing and coincidentally therewith, axial displace ment of said elements. 7. In combination with radio apparatus in 65 cluding a tuning device and a circuit control de vice, a tuning dial mechanism comprising dial plates arranged in spaced, parallel relation, means supporting said elements for both pivotal and axial displacement, a camming member op eratively associated with said suppporting means, adapted for effecting axial displacement of said dial plates, actuating mechanism for said cam ming means, operated from said circuit control 2,114,540 device, and means on said camming member, adapted coincidentally with the actuation of said camming member, to effect pivotal displacement of said dial plates. 8. In combination with radio apparatus in cluding a tuning device, a circuit control device, a panel and an opening in said panel, a tuning dial mechanism comprising dial elements ar ranged in spaced, parallel relation, means sup 10 porting said elements for both pivotal and axial displacement, means for biasing said dial ele ments to a position in register with said panel opening, a camming member opera'tively as sociated with said supporting means, adapted for effecting axial displacement of said dial elements, actuating mechanism for said camming means‘, operated from said circuit control device, and 5 said dial elements for axial displacement there of, said cam being actuated by said circuit con trol device, and a member movable with said cam and provided with spaced projections thereon ar ranged for engagement with said dial elements as the cam is operated, to effect pivotal displace ment of said dial elements. 1 11. In combination with radio apparatus in cluding a tuning device, a tuning dial mechanism therefor, comprising dial elements arranged in 10 spaced relation, a projection on each of said ele ments, means supporting said elements for both pivotal and axial displacement, a cam operative ly associated with said dial elements for axial displacement thereof, and a member movable with said cam and provided with spaced pro jections arranged for successive engagement with means on said camming member, adapted co the projections on said dial elements as the cam incidentally with the actuation of said camming member, to effect pivotal displacement of said dial elements out of register with said panel opening. is operated, to effect a successive pivotal displace ment of said dial elements. 12. In combination with radio apparatus in cluding a switch for adjusting the apparatus to 9. In combination with radio apparatus in cluding a tuning device, a tuning dial mechanism bands, a control for said switch, a plurality of therefor, comprising dial elements arranged in spaced relation, means supporting said elements nals in one of said wave bands, a panel for for both pivotal and axial displacement, a cam operatively associated with said dial elements for axial displacement thereof, and a member 30 movable with said cam and provided with spaced projections arranged for engagement with said dial elements as the cam is operated, to effect pivotal displacement of said dial elements. 10. In combination with radio apparatus in cluding a tuning device and a circuit control de vice, a tuning dial mechanism comprising dial elements arranged in spaced relation, means sup porting said elements for both pivotal and axial displacement, a cam operatively associated with receive signals in any of a plurality of wave dial plates, each bearing tuning indicia for sig concealing said plates, having an opening for re vealing the tuning indicia of any one thereof at a particular time, a shaft, means mounting said dial plates for independent pivotal movement and 30 conjoint translatory movement on said shaft, to Ward and from said panel opening, means for moving the dial plates as aforesaid, means opera tively interconnecting said switch control and said dial moving means, and a manipulating ele 35 ment for effecting joint actuation of said. switch control and dial moving means. VERNON C. MACNABB.