SU30168A1 - Shortwave with range switching - Google Patents

Description

In general, a number of radio devices, both transmitting and receiving, are often a necessary element of such an oscillating circuit in which the transition from one band to another would be accomplished with a simple switch. The usual disadvantage of this kind of switch circuits is that, especially on short waves, when part of the coil is turned on, the remaining tails create undesirable losses due to their connection with the part of the coil involved.

The subject of the present invention is such a shortwave circuit with a range switch that should eliminate this drawback.

According to the invention, the loop coil is divided into three coils connected in series, the fields of which are mutually perpendicular, and a contact knife is used to change the range, which can short-circuit individual coils and their combinations.

The drawing shows the proposed contour.

The self-induction coil of the oscillating circuit, divided into three coils /, 2, 3, the floor of which is mutual

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perpendicular, connected in series. The switching of the range is carried out by the switch 4, the main part of which is the contact blade 5, which closes the contacts 6, 7, 8, to which the ends of the coils /, 2, 3 are connected. In the case when the contact knife is placed in such a position that only contact 6 is closed, all three coils are connected in series with the oscillating circuit. If the contact knife closes the contacts of 6 TL 7, then only the coil 7 of the NC3 enters the circuit, since the coil 2 is closed by the contact knife. In the same way, for example, when a contact knife closes all three contacts, only coil 7 enters the circuit, and so on. Thus, such a circuit with a switch can, with an appropriate choice of coils, overlap five ranges.

The advantages of such a circuit are the ease of switching, the absence of tails and the losses associated with them, the possibility of obtaining a large range in the absence of replaceable coils.

The subject of the patent.

Shortwave circuit with a range switch, characterized in that the coil circuit is divided into three

series-connected coils, the field of which is mutually perpendicular, with a contact knife used for changing the range, which can short-circuit individual coils and their combinations.