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Show j RADIO FREQUENCY OOK-UP INCREASES RANGE I Receiving Area Enlarged By Device Explained By Expert JBv R. I.. DUNCAN, Director. Kndio InMltntc of America. ITn Increase the receiving area of - , . a radio sot, arrange it In a radio fre quency receiving i Ircuit BBBS This wll pick up sismals from f.ir- away points that could not otherwise 1 be detected. Differing from the nrranctement In, i audio frequency, it will be noted Hint 1 the radio frequency amplifiers placed ahead of the detector. Tins strengthens the signal? which would be too feeble otherwise to pass Into, the detector with enough strength to go through the process of rebtlfl-J I cation. In an audio frequenrs- clrcult th? amplifier la placed after the detertor to give greater volum to the Incoming Incom-ing signals after passing through the detector. I HOOK-l r Referring to the diagram, we havej the aerial with a variable condenser No. 5 and No. 10 Radio frequency fre-quency transformers. Xo. 9 Variable condP7i.r of about .fl005 microfarads, connected in the plate circuit of the second amplifying amplify-ing tube Xo. 11 Another varlahle conden ser. Xo. 12 Grid condenser of OOOl'o microfarad and grid leak If 1 mey-ohm mey-ohm Xo. 13 Detector tube. Xo. (14 Rheostat controlling filament fila-ment current in detector tube. Xo i f TVkicr coll giving regeneration regen-eration to the circuit. This may 1)6 j a variometer or a honeycomb, or duo-lateral, duo-lateral, coll. . No. 16 High resistance head I'hones shunted Uy fixed condenser. Xo. 17 Six-volt storage or "A" battery. No. 18 Variable "B" battery whk h nhould have 0 varying voltage from IT to 45 volts Thi amplifying tubes ,nJftf approxl-mately approxl-mately 46 volts on the plaflPwhile the detecto tube takes approxlmatclyl 22 1-2 volts. "B" batteries may be purchased with varying steps. Thes would be preferable In this hook-up. To further Increase the receptive power of the sot, audio amplification if j r f 1 i 17 ie t J 4r HOOK-IT OF RADIO FREQUENCY AMPLIFIER, I n series. No. 1 represents the antenna inductance. in-ductance. This should be a honeycomb honey-comb or duo-laterlal coll. the size to be used depending upon the desired wave length. Xo 2 and Xo. 6 Amplifier. or ' hard.' vacuum tubes. No. 3 and Xo. 7 Filament rheo-l rheo-l : stats. No 4 and No R Potentiometers which give finer variation of the filament fila-ment current. may be added after the detector for a still greater volume of reception |