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Show SUPER-REGENERATIVE WORKINGS EXPLAINED By PAUL F. QOW KV AjnertOS'fl Foramoal Rndlo Authority.! This In the fifth of n series of articles on tlc Armstrong super-regcneratle super-regcneratle rtmilt. Tho Inductive coupler used In the super-rcgeneratlve set may be assembled as-sembled very handily by Arranging I varometer of standard make along;-1 Dldi coll about five Inchea In dia- lineter around which 2f turns of num-' her 2 2 double magnet wire have been j wound The supporting form of this coll should be "1 SU b Bite that It mnv DS pet up close and still permit the ball of the variometer to turn freely I Care should be taken to see thnt the windings upon the coll are rnn-Ining rnn-Ining In the snme direction as those ;iipon the variometer on they sit side b side. If the connections Indicated In Figure 3 are used Otherwise regenerative re-generative action would be Impossible. Impos-sible. I Ith the completion of this coupler 'and the nlr core choke, and the purchase pur-chase "f Hie other parts listed in this column yesterday, the radio fan Is ready to hook up his set. OWeiCSHflHT Figure .1 The ndaOtlYS Coupler. To set this circuit In operation, carefully check all connections, according ac-cording with Figure 2, published here yesterday. Then plae a pair of head phones between the positive terminal of the "H ' battery und the inductance, 14, of the controller circuit j Then light the filament of the tube. Set condenser, C4. at ery near the full scale value Adjust C2. temperature of the filament fila-ment and "B" battery until S r' high pitched audible tone Is heard. Rcmoo the phones from the con- Irnller circuit. It continues to OSCll-ilate. OSCll-ilate. Tube R in next lighted and the pick-up circuit rtnd tickler htc adjusted adjust-ed for n given Ptntlon until the clr-1 CUll Is oscillating strongly. If a fairly strong "pluck- la heard in the telephone, tele-phone, both when the finger Is placed upon, and removed frr.ru. the grid I terminal of the tube R, the circuits! are In oscillation. AD.M KTMENT, . In advancing th- tickler from a i minimum setting toward n maximum I a point win ie passed where n greal i hissing nol?e Is heard in the telephones. tele-phones. The advance of the tickler control hnvlng been continued. t he I hissing begins to lessen and finally, lulmost If not entirely stops. At that time the circuit are approximately ap-proximately properly adjusted for reception re-ception In order to reach this stage, some llttln adjustment of filament current. "B" battery, and circuit. may be necessary. After tho proper combination combin-ation Is found, however, practice with the circuits will soon enable their rendy use. (Copyright, 1922, NBA Service ) |