A sound-on slide projector including a scanning device for magnetically recording or reproducing sound on a slide. The device traces a spiral locus along the magnetically coated frame of the slide film without using any guiding means. The projector also has detecting means for sensing positions of the magnetic head. The detecting means energizes means to reset the magnetic head, which cooperates with magnetic head detaching means disposed between the slide frame and the scanning device. Guard sw...

A figure illuminating discharge tube having one common anode and a plurality of cathodes necessitated to illuminate one digit of the decimal number upon application of voltage to the anode and cathodes, which comprises means for effecting a glow discharge between the anode and any one of the cathodes with fairly quick efficiency as compared with the conventional tube of a similar character. To this end, an auxiliary cathode directly connected with a power source is provided for maintaining a gol...

An identification card having six-digit numerical information is prepared which comprises six information unit or digit hologram areas arranged in a predetermined direction, each having a hologram prepared based on an optical pattern of a combination of opaque and transparent portions in four predetermined bit positions being located commonly to all the information units for identifying a decimal number in the corresponding digit. The card is verified by comparing a bit signal representative of ...

A light valve of the present invention comprises an oblique cut single crystal plate of strontium barium niobate (SBN), which is placed in a plane vertical to a light transmission; a plurality of transparent strip electrodes which are placed, at right intersections with each other, on the front and back surfaces of the plate; means for generating an electric field within the single crystal, in parallel with a light transmission direction, in a given region of the plate to be addressed by selecti...

An electrochemical potential memory device comprising a cathode mainly comprising silver, an anode mainly comprising silver chalcogenide, and a silver ion conductive solid state electrolyte sandwiched therebetween is connected to a current source for selectively driving the device in a charging state or discharging state and to a high input impedance direct current amplifier responsive to the terminal voltage of the device, and a timing operation signal proportional to the lapse of the charging ...

A vacuum cleaner including a two-stage filtering system positioned within a cleaner body for filtering the air before it passes through an electric motor fan unit. The two-stage filtering system comprises a first dust collecting receptacle having incorporated therein a filtering screen of a relatively large mesh size and detachably positioned within the cleaner body. The filtering system further includes a second filtering member of fine mesh size located immediately downstream of the first dust...

A tuning device for a UHF tuner includes a rotatable drum rotatable step-by-stop by turning a tuning shaft of the tuning device, a plurality of adjustable control elements loosely carried by the rotatable drum and a tuner operating member for operating the tuner to select a desired one of UHF channels. The tuner operating member can be operated by the adjustment of any selected one of the control elements thereby permitting the tuning of the tuner.

In a solid coulometer comprising two opposite layers, of which one is made of active metal and the other is made of inactive metal, and a layer of solid electrolyte of high iron conductivity sandwiched between them wherein the active metal ion is migrated and deposited on the inactive metal layer on charging and then the deposited active metal ion is removed from the inactive metal layer and re-depodited on the active metal layer on discharging so that an over-voltage is produced at the completi...

A high-frequency heating apparatus includes a supply source for supplying high-frequency energy into a conductive heating chamber. Two pairs of stirring blades mounted on a rotary shaft inside the chamber are positioned relatively to the supply source so that a substantial portion of the radiated energy is intercepted and reflected by the blades to afford more uniform heating of materials within the chamber. The generally elongated stirring blades are mounted tangentially of the circumference of...

An electronic oven comprising an oven-defining structure equipped with means for effecting the browning action on an object to be heated, said browning means including means for creating a forced circulation of air and a heating assembly, whereby hot air of relatively high temperature can advantageously be directed toward the object so that the browning or scorching action can be performed in a short time as rapidly as the object can be heated solely by the application of high frequency energy.