Патент USA US2111711код для вставки
March 22, 1938. 2,111,711 J. VAN SLQOTEN COMBINATION RADIO RECEIVER AND PHONOGRAPH Filed March 4, 1936 bilh DI P .blh b ID D 11 —1 1 D \ v . .D 6 INVENTOR .J. VAN SLOOTEN BY . /" ATTORNEY 2,111,711 Patented Mar. 22, 1938 PATENT OFFICE UNITED > STATES 2,111,711 COMBINATION RADIO‘ RECEIVER. AND PHONOGRAPH Jacob van- Slooten, Eindhoven, Netherlands, as- . signor to N. V. Philips’ Gloeilampenfabrieken, Eindhoven, Netherlands Application March 4, 1936; Serial No. 67,004‘ In Germany March 18, 1935 7 Claims. (01. 179-10011) This invention relates to a radio receiving set which is adapted at the same time for reproduc ing talking machine records. With such sets it is known when reproducing records to insert 5 the pick-up in the input circuit of the detector tube which exclusively operates as a low fre quency ampli?er in this case. After that the ampli?ed voltages are ampli?ed again in a nor— mal manner by the further low frequency 19 amplifying part of the set ‘and supplied to the loudspeaker. In many cases, however, this meth od of changing-over, which is simple and assures sutlicient sound-strength is’ not feasible, for in according to the invention which is relevant to the latter. ' ‘ When receiving radio signals the high or inter mediate frequency oscillations are supplied be tween the grid 18 and the cathode 19 of a screened-grid tube I. Through the switch ‘I, which bears on the left contact during radio reception, the screen-grid I1 is connected to a point of positive voltage, for instance to the posi tive terminal of the supply, so that the resistance 5 is short-circuited. 0 The anode is connected to the positive pole of the supply through a tuned circuit It. The ampli?ed voltages are supplied stance when the detector valve is a diode. In 15 these cases it would be possible of course, to to the detector circuit through a coupling con denser 9. The detector circuit comprises a diode interpose the pick-up in the input circuit of the low frequency amplifying part of the sets. It 2, a resistance 1 l, whose function will be set out hereinafter, and a potentiometer resistance 12, has been found, that in this case the sound from which low frequency voltages are taken off through a contact I3 by the adjustment of which the sound strength can be controlled. The re 20 sistance H may be connected in series with a strength is insufficient when reproducing the record, so that it is necessary to interpose either an ampli?er or a transformer, which is expensive. As an alternative the pick-up may be inserted in the input circuit of the last high- or inter a low frequency ampli?er in this case. When making use of diode recti?cation the diode de tector tube may then be made inoperative dur voltages are supplied to the output Valve 3 in whose output circuit a‘ transformer 14 may be in serted, whose secondary ‘winding is connected to It will be obvious that the changing-over arrangement becomes fairly complicated in this way. The object of the present invention is to pro vide a circuit arrangement in which one of the high- or intermediate frequency tubes is adapted 40 4 UT I0 is designed for carrying off the high- or inter mediate frequency voltages. The low frequency _ denser should be enlarged. 03 U high frequency choking coil 20. The condenser mediate frequency tube which should operate as ing the reproduction of records, since it con stitutes a short-circuit for the low frequency 30 currents, and when, as is customary, a tuned cir cuit is inserted in the output. circuit of the tube, this tuned circuit should be replaced by a cou pling resistance. Moreover, the coupling con in a simple manner for low frequency ampli?ca tion when reproducing records. According to the invention the screen grid of the said tube is used as an anode when records are reproduced. For this purpose a coupling resistance is inserted‘ in the screen-grid circuit, the screen-grid being connected to the input cir cuit of the low frequency amplifying part of the set through a coupling condenser. It has been 50 found that in this manner a suf?cient preliminary ampli?cation of the low frequency currents can be achieved. ' The invention will be more clearly, understood by reference to the accompanying drawing repre 55 senting by way of example, that part of the set 5 the loudspeaker 15. .When changing over from the reception of radio signals to record-reproduction by chang ing over the switch 6, the pick-up 4 is inserted in the input circuit of the tube 1. At the same time the commutator ‘i is changed over thus con tacting with the right contact, the resistance 5 being inserted in the screen-grid circuit. In this case the tube I operates as a low frequency ampli ?er, the screen-grid ll serving as an anode. The low frequency. voltages are supplied to the re sistance 12 through the coupling condenser 8. The resistance ll prevents the low frequency voltages from ?ow off through the diode. I claim: 5 1. In amplifying apparatus, an ampli?er in- ' cluding an electronic tube having an anode, a cathode, a signal grid and an auxiliary electrode, a high frequency input circuit for the tube con nected between the control grid and cathode thereof, a low frequency input circuit and switch ing means for connecting the low frequency input 50 circuit between the control grid‘and cathode of the tube, a high frequency output circuit for the tube connected between the anode and cathode thereof, a low frequency output circuit and switching means for connecting the low-fre 55 2 2,111,711 quency output circuit between the auxiliary elec trode and the cathode of the tube. 2. In amplifying apparatus, an ampli?er in cluding an electronic tube having an anode, a cathode, a control grid and an auxiliary electrode, a high frequency input circuit for said tube connected between the control grid and the cathode, a high frequency output circuit for said tube connected between the anode and the oath 10 ode, a detector connected in the output circuit of said electronic tube, and an audio frequency ampli?er connected to the detector, a low fre quency circuit and switching means for connect ing the low frequency circuit between the con trol grid and cathode of the ?rst tube, and means including a switching device for connecting the auxiliary electrode of the ?rst named tube to the ing device also being adapted to short-circuit the resistance connected between the auxiliary electrode and the positive terminal of the source of space current, an audio frequency ampli?er including a control electrode, a cathode and an anode, and means including a condenser for con necting the control electrode to a point of that one of said two mentioned resistors between the anode and cathode of the diode which is nearest the cathode. 10 5. In amplifying apparatus, a high frequency ampli?er circuit including an electronic tube hav ing an anode, a cathode, a signal grid and an auxiliary electrode, external circuits for said tube forming a signal grid-cathode circuit, an auxilia ry electrode-cathode circuit and an anode-cath ode circuit, a low frequency ampli?er provided audio frequency ampli?er. with an input circuit and an output circuit, a 3. In a radio phonograph system, a high fre quency ampli?er including a space discharge de vice having an anode, a cathode, a control grid and auxiliary electrode, a diode detector con nected between the anode and cathode of said space discharge device, an audio frequency ampli ?er connected to the diode output, a phonograph pick-up means and means including a switch for detector interposed between the anode-cathode circuit of said electronic tube and the input of 20 the low frequency ampli?er, a low frequency cir cuit including a photograph pickup device, switch ing means for connecting the low frequency cir connecting the phonograph pick-up means be tween the control grid and cathode of the ?rst named tube, and switching means for changing the characteristics of the ?rst named tube so that the auxiliary electrode acts as an anode with re spect to the control grid and cathode, and to connect the auxiliary electrode to the audio‘ fre~ quency ampli?er when the ?rst named tube is adjusted to act as an ampli?er for phonograph signals. 4. In a radio phonograph device, an ampli?er including a space discharge device provided with an anode, a cathode, a signal grid and an auxil iary electrode, a high frequency input circuit connected between the signal grid and the oath ode, a low frequency input circuit including the phonograph pick-up device and a switching means for connecting said low frequency input circuit between the signal grid and the cathode of said cuit to the signal grid-cathode circuit of said electronic tube, and switching means for con 25 necting said auxiliary electrode-cathode circuit of said electronic tube directly to the input of said low frequency ampli?er when the low fre quency circuit is switched into the signal grid cathode circuit of said electronic tube. 30 6. An arrangement as described in claim 5 characterized by that the auxiliary electrode oper ates as an anode when the last named switching means is operated to connect the high frequency ampli?er and the low frequency ampli?er di 35 rectly. '7. In a radio phonograph combination, a high frequency ampli?er circuit, a detector circuit and a low frequency ampli?er circuit coupled in cascade in the order named, said high frequency 40 ampli?er including an electronic tube having an anode, a cathode, a signal grid and an auxiliary electrode, a circuit including a phonograph pick up device, means for connecting said circuit in the input of the high frequency ampli?er, an ?rst tube, a diode recti?er, means including a auxiliary output circuit for said high frequency coupling condenser for connecting the anode of ampli?er comprising means connected between the auxiliary electrode and the cathode, said the ?rst tube to the anode of the recti?er, a connection between the anode and cathode of the recti?er including an inductance coil and a pair of resistors in series, means including a resistance element for connecting the auxiliary electrode of the ?rst named tube to a positive source of cur rent, and means including a tuned circuit for 55 connecting the anode of the ?rst tube to the posi tive terminal of the source of current, means means including a switching device, and. means connecting said last named circuit to the input of the low frequency ampli?er, said detector cir 50 cuit including means for preventing energy trans ferred from the phonograph pick-up device through the ?rst ampli?er circuit from travers ing the detector circuit when the last named switching means is operated so as to connect the comprising an operable switching device and a ?rst named ampli?er to the low frequency ampli coupling condenser in series, adapted to connect ?er through the auxiliary output circuit. the auxiliary electrode of the ?rst tube to a 60 point intermediate said two resistors, said switch JACOB VAN SLOOTEN.