US2492698A - Radio receiver - Google Patents

Description

Dec. 27, 1949 HILLS 2,492,698

RADIO RECEIVER Filed Oct. ,16, I945 I s Sheets$heet 1 4 F. M. HILLS Dec. 27, 1949. v

RADIO RECEIVER.

3 Sheds-Sheet 2 Filed Oct. 16, 1945 Dec. 27,1949. -F. M. HILLS 2,492,698

RADIO RECEIVER Filed 001' 16, 1945 3 Sheets-Sheet 3 Patented Dec. 27, 1949 UNITED cFF-I'CE Appnmip cqt b r 1c, 1945; Serial N01. 622,582 In Great Britain November 8:, 194,3

1 Claim. '(61. 25 14) 2 fel rfi id i fcciy intndd t6 be pm -ged in o a iig ht pj dan't. Itis tp lie; 'q'ndc stoqil iowever, thai; yvh 'ei .Su' h ia sh'qrt iength Of cable is en YQF it w ll 0191, h e 3 3 tha ll l i i wici; the so vjcepl ljagl midget r cei ers now on the markeg and which f dqri'sidmble length to 1 j H aj ice. Su'ch midget rec'eijl'i, n any c'as arc much too heavy to be, an ordinary light socket,

i' ifien 'Siiicc it is it is important that th i f q' vei' b? k t small as bO'SsibI, subjcct ijq thc rcqiiircd p erqrcmanc of h cuit; T aq d ly r i er n bodx n "thew .cr sfi i nvent n vw fi nofiin oir' thgn 2 mums; and 15 preferably not a ih' W nche n. an o eral di n o f z' e b' mod fi 'd f r e ve cpih is; designed 51st} to pci fcrm any qthtgi functi'dr1. ugs ipmay rqj orbe built ii t'q, a electric lingi'shadc '0';- i fl'ectgr in which case it; may; fdr exan file, be it; th 'shapc o f a domed conical oi p'y'ramid'al b'dx pqticcably greater than 6 inches in izwo qimensionsbui; i zdrrspondipgly les s in its h dd' in HInf' qch an r ai emn S a m be r v d d W thin the box o i eo eifriiits idt ncfissarily fprming part of the reciv'er circuit, g; lctric lamps.

.A .i ei l i cg it hi .n "re s na le. er rmahc within the iimit of Weight indiqateq above is d esi ne acsprqling iorct e, n e n by a e eleitidi 63 li t-Wi h qo in tsh the v s us d ar a ffirablwf t qkinfl o nin tl'ie' rachc ihdiistry jps mid gt; ba 'itani or miniatu'r valves; grid 111' thc circuit; (which may com: prise .qnfe or nic jc v a lvcsj it is prcferred that at l a t b le; and nri rably a va ve is a mu i valve, i, cgimpri 'ses i i cr b evaciiatgd envelope piitcd, lectrod wm ri si .h i'rw" w 3 those known under the code number 12B8-GT (embodying a triode and a pentode) and 32L7-GT (embodying a diode or /2 wave rectifier and a beam power output).

In order to be operated by current directly from the domestic supply voltage the valve cathode heaters may be connected in series with one another and with a suitable load. In one form of the invention it is preferred that this load shall comprise one or more electric lamps of suitable total voltage and wattage rating and a socket or sockets may conveniently be provided in, or attached to, the receiver casing to receive it or them. If desired an alternative resistance load may be provided, e. g. a resistance component adapted to be plugged or screwed at will, in place of the lamp, into the lamp socket, or as a resistance built into an end cap of the receiver casing suitable to replace the removable end cap which incorporates or supports the lamp socket or sockets. Alternatively such a resistance may be built permanently into the receiver casing and switch means provided to bring it into circuit and to cut out the lamp (without physical replacement) if and when it is desired to operate the receiver without the light. The same or other switch means may be provided or adapted to allow light to be switched on without putting the receiver into operation. Such means may be located at the domestic switch or in the receiver casing. In a further alternative the lamp shade may be formed from a resistance mat the resistance of which forms the load. In a still further alternative I may employ a lamp bulb with a secondary ballast resistance in the same envelope.

It should be understood that the above-described arrangement of series connected cathode heaters does not exclude the use, within the scope of this invention, of any other convenient arrangements, e. g. a series-parallel connection between heaters and/ or the load, with or without suitable shunt elements, if necessary, to ensure the required values of voltage and current for the heaters, and the best use of the remaining power not required by the heaters.

In some cases, also, I may employ filament type valves in place of the valves above referred to, in which case direct current may be supplied to the cathodes by means of a suitable rectifier (if the supply is from A. C. mains), and here again a series or parallel or series-parallel arrangement may be adopted.

As an aerial it is preferred to employ one of the electric supply cables and incoming signals may be picked off therefrom by suitable coupling: but if this is not convenient or desirable I may employ a separate aerial of any convenient form, e. g. the wire frame of an electric lamp shade mounted on the same pendant as the receiver. Means may be included in the circuit to eliminate mains hum and/ or other interference which may originate from the use of a supply cable as an aerial and/or from the close proximity of any casing may itself form the upper portion of the shade, being, for example, a shallow flat or domed box incorporating centrally the loudspeaker, having radial or sectored compartments or recesses to receive lamps and other compartments to house the receiver circuit components, with means round the edge to support beading or other artistic drapery or decoration.

While the shape of the receiver casing may assume any of a number of forms, it is desirable that its lateral dimensions shall be limited in the vicinity of the connector, in order that when it isplugged into an electric socket the casing will not interfere with fittings already mounted on, or adjacent to the socket. This consideration is of less importance where, as suggested above, the casing itself forms part of a fitting, e. g. a lampshade. The centre of gravity of the assembly should be on the axis of the connector in all cases in which the latter is rigidly associated with the receiver casing. It is also preferred that the axis of the loudspeaker shall be in alignment with the said connector axis. The casing may conveniently be formed of moulded parts of any suitable artificial plastic, and the circuit elements mounted upon a separate frame or platform removably insertable into the outer casing for ease of assembly and access.

In one convenient modification the casing may be in the form of a cylinder of circular, rectangular or an other desired horizontal cross-section,

or the casing may be slightly conical in. or near to one end of which is mounted the loudspeaker, and having in the closure or end cap at the other end a socket suitable to receive an electric lamp which forms the load in the valve cathode heater circuit. By means of a framework or spider extending to the rigid speaker surround or to the casing wall adjacent thereto, there is carried a plug in line with the speaker axis, adapted to engage the socket of a domestic light pendant and thus both support th receiver and supply electric power to the circuit. Alternatively the lamp-socket and the supporting plug may be in interchanged positions, i. e. adjacent to the speaker and at the I opposite end of the receiver respectively- In either case suitable adaptors may be provided in order that the user can at will invert the receiver from its normal position and utilise it in the inverted attitude.

In such a casing the frame or platform carrying the valves and other circuit components may be of any suitable form, as for example, it may be in the form of a plate extending across thebe held between two apertured plates or ringsextending across the casing, the remaining components being arranged in the space within the valves and/or on the other face of the plate or plates. In any modification of the invention I preferably dispense with the conventional valve holders or bases, and use spring plugs direct on the leads from the valve components.

To the end of the casing in which is located the loudspeaker there may, if desired, be removably secured a flared mouthpiece forming an and may carry the spider or framework bearing the supporting connector. If desired the casing 7. of the kind described above or in any other small receiver, there is envisaged, according to this invention, the use of a small relay-operated switch. This may comprise a coil, located across the sup ply mains or in the H. T. supply, actuated by a switch to operate an armature whereby a pawl is caused to turn a ratchet wheel which carries or moves an on-off switch or the wiper arm of a multi-contact switch. In the latter case, for ex- :ample, movement of the arm from one contact to the next brings into or removes inductance and/ or'capacity in the circuit and thus tunes it to a 'difierent frequency. The arm may move one step :for each depression of the relay-actuating switch. Such an arrangement is more compact than separate press-button tuning to any one of a limited number of frequencies for which the receiver has preset tuning. An example of such tuning for two different frequencies is shown in Figure l'of the drawings in which a solenoid or relay winding h is arranged in the high tension circuit so that the 'H. T. produced in the r-ectifier'V l has to pass through the solenoid windings with the result that as soon as H. T. passes through the circuit, the solenoid is energised. The relay is adapted to operate a spring-load pawl and ratchet mechanism which actuates the switch'contacts h so that for successive positions of the ratchet mechanism produced by successive operations of the light switch, the tuned frequency will first be determined by the tuned inductances c and e, and will then be altered by the switching of the additional pre-set capacitances (or trimmer condensers) d and e across such tuned inductances. Where an energised loud-speaker is used the solenoid may be employed as the switching coil.

If desired, in any of the modifications of the invention described above two or more loudspeakers may be included in the circuit for greater volume of accoustic output. Thus the casing may carry two loud-speakers one on each of opposite ends or sides: or a receiver with one speaker mounted in the casing, as described above,'may be used in conjunction with another loud-speaker, e. g. in the form of a lampshade, as also described above.

In Figure 2 I have shown a form of receiver in accordance with the invention applied to a light pendant, the receiver being shown at i, the lamp bulb at k and the shade at Z. In this form the speaker is at the bottom of the casing adjacent the lamp, but it could equally well be disposed at the upper side of the casing.

Figure 3 shows a similar arrangement but applied to a lamp standard.

Figure 4 shows the arrangement of radio re-- ceiver parts within the casing'i of Figs. 2 and 3, the reference numerals referring to the same parts as in the diagram of Fig. 1.

It should be understood that the invention is not limited solely to the details of construction and arrangement described above since modifications thereto may be introduced as and when they, appear desirable in order to carry theinvention into effect and achieve the results indicated under 8. difierent conditions and requirements which have to be fulfilled without departing in any way from the' scope of the invention. For example, by choosing valve heaters'su'ch that'when in series the total'voltage taken by the heaters-is equal to the mains voltage the lamp or other load will not be necessary and in such case if I combine a lamp with the receiver it may be switched on and off' for lighting purposes only. Further, when a moving iron speaker movement is employed as above described the. winding may be used in the plate circuit of the output valve in place of the transformer, or, alternatively, the relay coil above referred to can constitute the output valve plate impedance, again dispensing with the output transformer. I claim:

In a combined electric lamp and radio receiv ing apparatus, a ventilated casing having a longitudinal central axis of symmetry and bounded by two spaced-apart end surfaces both perpendicular to said axis, a complete assembly of radio receiver circuit components removably mounted in said casing for ready removal and repair, a

screw-type electrical power connector secured to a'central portion of one of said end surfaces, power connections between said connector and said assembly for supplying operating power to the latter, whereby said connector may be screw-coupled to a complementary power supply fixture'to energize the radio receiver circuitcomponents and simultaneously to support said casing in'a predetermined relationship to said fixture, a screwtype power connector secured to a central portion ofthe' other end surface, power connections from said first connector to said second connector adapted to energize an electric lamp connected to the latter connector, and a loudspeaker mounted entirely within said casing adjacent the first mentioned end-suriacein a centered position on said axis for directing sound outwardly of said casing.

FRANK MAURICE HILLS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Great Britain June 2, 1938

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