US1837999A - Radio receiving system - Google Patents

Description

Dec. 22, 1931. A. RlSTOW RADIO RECEIVING SYSTEI Filed Feb. 27, 192

2 Sheets-Sheet 2 Ely-'1 Jlfarney Patented Dec. 22, 1931 I I i UNITED STATES PATENT OFFICE ALFRED RIS TOW, OF BERLIN-NEW COLOGNE, GERMANY RADIO RECEIVING SYSTEM Application filed February 27, 1928, Serial No. 257,224, and in Germany February 22, 1927.

An application was filed in Germany, Febof example, in combined Figures 1 and 1a ruary 22, 1927. of the accompanying drawings, while Figure The present invention relates to radio re- 2 shows a feature appearing in Figure 1 ceiving systems in which the point at which more in detail v 5 reception actually occurs is remote from the The arrangement depicted comprises two apparatus aiiected by the aerial radiations, receiving apparatus 151- and E2 with a It has been found that owing to well-known singleknoh control constructed in such a causes of various kinds, it is impossible to manner that by turning the tuning knob install receiving installations which should from the zero mark on the scale the aerial 10 be capable at any 'momentof receivingmesand the heating circuit are switched in. It

sages in cities. Examples of such installawill be shown later on that, one receiver can tions are subscribers toa press service, stock be, worked only after the other one has been exchange service or weatherservice and reswitched oil. The telephone leads T1 and ceiving installations of public authorities; 'T2are connected to the winding VVl of the All these installations mustbe capable at any ring repeater U1, the secondary windingof moment of receiving in a reliable manner the Which is tapped in the centre, whilst to the messages intended for them, as on the one outer ends the transmission lines L1, L2 are hand dependence isplaced on them and on connected and lead tothe tapped winding the other hand such messages are mostly sent W3 of the ring repeater U2, the secondary 0 only once. In order to ensure adequate rewinding of which contains a telephone T or ception, such receiving innallat-ions must be other signal r produci g apparatus. located out of towns, the reception room in F or eflecting the remote control, two the town being connected to the receiving three-pole control keys S251 and St2 are proinstallation by means of a telephone line. vidcd. The negative pole of the battery B1 The drawback of this arrangement is that is connected to the contacts a of the two it is necessary to have a special stafi for the keys, the contacts 0 to the positive pole, receiving apparatus who have nothing to do whilst the contact I) of the key St2 is con but to tune it, whilst the messages are renected to earth'and the contact I) of the key ceived by the staff in the town. The condi- Stl to the tapping of the winding V3, with tions are similar in all cases in which the the interposition of a milliammeter MA. transmitting and receiving installation is .to When the key stl. is depressed, the positive be worked from a central station. In order pole of the battery will be connected'to the to avoid disturbance by the transmitter, it is line and the negative pole to earth, but when necessary to arrange the receiving installathe key 852 is depressed, the positive pole tion separately and spaced from the" transwill be connected to earth and the negative 35 mitter or from the central working station. pole to the line. By depressing the two According to the invention, these drawkeys as desired it is therefore possible to backs are avoided by a remote electrical consend currents into the transmission line in -trol of the receiving apparatus which is efeither direction.

fected by means of the transmission line. In The tapping of the winding W2 of the order to guarantee reliability of reception ring repeater U1 isconnected to earth with even in the event of a valve burning out, two the interposition of a resistance R and of a or more receiving apparatus which can be two-polerelay MR so that, bythis circuit, the

- switched in and out at will by means ofthe control circuit is closed through the earth.

said remote control are provided. The cost At the same time the circuit is also closed of the second receiving apparatus is compenthrough the resistance R and through the sated for many times by economy in the atrelay Rt to earth. According to the directendant stafl. tion of the control current, the relay MR One way of carrying the invention into will be thrown over in'one direction or the effect is diagrammatically illustrated by way otherand in that way a series motor HM,

which effects the tuning of the receivers, is correspondingly connected to the battery 132 and its direction of rotation determined accordingly.

The mechanical arrangement will be explained first for the receiver E2:-The tuning knob K of the receiver E2 is connected, with the interposition of various gear wheels, to the movable part of a clutch magnet TM2, to which current is supplied through two slip rings 1 and 2. The driving spindle of the clutch magnet engages, by means of another gear wheel, with the gear wheel Z which is mounted on the same spindle as the resistance R and the operating wheel Sch of a three-pole switch DR driven by the series motor HM with the interposition of worm wheels or other gearing. The resistance R comprises an annular winding which is rigidly secured to the spindle, whilst current is supplied through the slip ring 3 and the brush l.

The three-pole switch DH is shown in detail in Figure 2. On the operating wheel Sch two stops or tappets are mounted one at each side and suitably displaced relatively to each other. When the operating wheel is turned clockwise, as assumed by way of example in the drawings, the lever H1 of the three-pole switch will be rocked and brought into the position shown in dotted lines until it engages with a spring F1 mounted on a magnet, the winding of which is always eX- cited. The construction in the present ex ample is such that the spring is magnetized and is in a position to hold the lever H1 in the dotted position, but some other arrangement, say with a permanent magnet, could also be employed. When the operating wheel continues to move in the direction. indicated, the spring will be compressed until the stop a1 slides off the lever H1, when the spring will return to its position of rest. but will still hold the lever H1, fast magnetically. The current supply points are the centres of rotation of the lever, and the spring F1. The result of the magnetic retention is that the circuit will not be broken in spite of the operating wheel continuing to rotate, but if the direction of rotation is reversed, the lever H1 will be detached from the spring only at the moment when the stop c1 touches the lever H1, and the contact will be interrupted. The setting of the operating wheel mustbe such that at the beginning of the contact closing, the clutch magnet TM2 and therefore the tuning device of the receiver which at this moment should be at zero. will be switched on. A rotation of 180 on the tuning scale may correspond for instance to a rotation of 200 of the operating wheel; by a rotation of 200 the whole range of tuning of the receiver E2 will therefore have been traversed. If the operating wheel Sch is turned baclm'ards, then at the moment when the marking 0 on the tuning scale is reached, the contact by the lever H1 will be broken and the receiver E2 switched off. If the operating wheel continues to rotate in the same direction (that is to say in the direction opposite to that assumed in the drawings), after a short time the stop a2 indicated at the other side of the wheel will strike the lever H2, and therefore the clutch magnet TMl of the receiver E1 will be switched in. The same thing is repeated as before, with the difference that an increase in the tuning scale reading corresponds to anti-clockwise rotation of the operating wheel and vice versa. This can be easily obtained by a correct arrangement of the transmission gear. In Figure 1 the three-pole switch is shown somewhat differently for the sake of clearness. lVhen the relay MR is thrown over in the manner above described by depressing a key 55/1 or @2 2 the motor ill i will rotate in a corresponding direction. At the same time the wheel Sch of the three-pole switch will start and close by means of the lever H1 the following circuit t-negativc pole of the battery B2, contact of the relay R25 the relay acts at the moment when the relay MR is thrown over), centre of rotation of H2, contact spring F1, slip ring 1, clutch magnet TM2, slip ring 2, positive pole of the battery.

The motor will continue to rotate until the depressed key is released but when the circuit is broken the relay MR will return to the position of rest and the relay Rt will fall off and break the circuit of the clutch magnet. The latter will instantaneously release, whilst the motor has time to run down slowly; if the clutch magnet and the relay Rt were not provided the tuning would be lost again owing to the running down of the motor.

If it is desired to pass from the receiver E2 to the receiver E1, first the tuning of the receiver E2 is brought to Zero and then the re-- ceiver E1 is tuned in a similar manner.

It is obvious that the tuning could be effected simultaneously with the listening, and that it is possible to go back with the tuning at will even if the range has been passed.

As the resistance R is rigidly secured by a common spindle to the operating wheel of the three-pole switch, to each position of the switch there will correspond a given value of the resistance. As the other resistance values of the circuit, viz., the repeater coil, line and relay MR are constant, the milliammeter MA provided in the listening room, can be calibrated to the position of the operating wheel of the three-pole switch and in. that way the tuning of the receivers can be read on the milli ammeter.

l Vhat I claim is:

1. 1'. radio receiving system comprising in combination a receivinnapparatus embodying two receivers and a signal reproducing apparatus located at a distance from said receiving apparatus, a transmission line connecting said receiving and signal reproduc-V ing apparatus, means in proximity to' said signal reproducingapparatus for sending through said transmission line an electric current, control keys in proximity to said signal re roducing apparatus for varying combination a receiving apparatus and a sig nal reproducing apparatus located at a distance from said recelving apparatus, a transnission line connecting said receiving and signal reproducing apparatus, means in proximity to said signal reproducing apparatus for sending through said transmission line an electric current in either direction, tuning means in said receiving apparatus, a motor responsive as regards direction ofrotation to said current, an operative connection between said motor and said, tuning means, a clutch in said connection, means whereby said clutch is engaged on rotation of said motor in one direction, and means for retaining said clutch in engagement independently of the continuance of said rtation.

3. A radio receiving system comprising in combination a receiving apparatus and a signal reproducing apparatus located at a distance from said receiving apparatus, a transmission line connecting said receiving and signal reproducing apparatus, means in proximity to said signal reproducing apparatus for sending through said transmission line an electric current in either direction, tuning means in said receiving apparatus, a motor responsive as regards direction of rotation to said current, an operative connection between said motor and said tuning means, a clutch in said connection, means whereby said clutch is engaged on rotation of said motor in one direction, means for retaining said clutch in engagement independently of the continuance of said rotation, and

means for disconnecting said clutch when said current is stopped or on reversal of said rotation.

l. A radio receiving system comprising in combination a receivi apparatus and a sig- D nal reproducing apparatus located at a d1stance from said receiving apparatus, a transmission line connecting said receiving and signal reproducing apparatus, means in proximity to said signal reproducing apparatus for sending through said transmission line an electric current 1n either direction,

tuning means in said receiving apparatus, a motor responsive as regardsrdirection of rotation to said current, an operative connection between said motor and said tuning means, a clutch in said connection, means whereby said clutch is engaged on rotation of said motor in one direction, and means responsive to the cessation of said current for stopping said motor and for immediately disconnecting said clutch although said motor continues rotating during a runningdown period.

5. A radio receiving system comprising transmission line to which said receivers and said signal reproducer are connected, tuning means for each of said receivers, operating mechanism for said tuning means, and remote control means located in proximity to the signal reproducer and controlling over said transmission line said operating means for selecting and tuning either receiver.

6. A radio receiving system comprising two receivers, a signal reproducerv located at a point distant from-said receivers, a twowire transmission line to which said receivers and said signal reproducer are connected, a tuner for each of the receivers, operating means forv the tuners including a motor rotatable in opposite directions for selecting and tuning therespective receivers, and remote control means located in proximity to the signal reproducer for supplying current of opposite polarity over said transmission line for controlling the direction of rotation of the motor.

. 7. A radio receiving system comprising in combination two receivers, a signal reproducer located at a distance from said receivers, a transmission line to which the sig-' nal reproducer is connected, operating means for the tuners of the receivers including a motor rotatable in reverse directions for ac tuating said operating means for selectively tuning the respective receivers, coupling devices for automatically connecting the motor with the tuner of one or the other of the receivers on the rotation of the motor in opposite directions, and means for supplying an electric current in either direction through said line to rotate the motor in one direction or the other.

8. A radio receiving system comprising in combination a receiving apparatus incliiding a tuner and a signal reproducing apparatus located at a point distant from said receiving apparatus, a line circuit to which the reproducing and the receiving apparatus are connected, means in proximity to said signal reproducing apparatus for transmitting a current through said line circuit to control the operation of the tuner of the receiving apparatus, means in proximity to said receiving apparatus responsive to said control 7 two receivers, a signal reproducer located at a i distant polnt from said receivers, a two-wire current for continuously tuning said receiving apparatus between widely different Wave length ranges, a device variable with the setting of said tuning and located in the path of flow of said control current and operable to vary said current, and an indicator in proximity to said signal reproducing apparatus responsive to said variable current.

9. A radio receiving system comprising in combination a receiving apparatus and a sig nal reproducing apparatus located at a point distant from said receiving apparatus, a transmission line connecting said receiving and signal reproducing apparatus, means ineluding a plurality of keys in proximity to said signal reproducing apparatus for connecting to said transmission line currents of opposite polarity, operating mechanism including a polar relay responsive to said current for actuating the tuning means of said receiving apparatus, an electrical resistance variable with the setting of said tuning means and located in the path of How of said current, and an indicating instrument re sponsive to said current in proximity to said signal reproducing apparatus.

10. A radio receiving system comprising a plurality of receivers, a signal reproducer located at a distance from said receivers, a sig nal transmission line extending between the receivers and the signal reproducer, tuning mechanism for each receiver, operating means for the tuning mechanisms, a selector "for selecting the receiver to be tuned, and remote control means located in proximity to the signal reproducer and serving, when actuated, to control over said signal transmission line the operation of said selector and said operating means.

In testimony whereof I have affixed my signature.

DR. ALFRED RISTOVV.

Images