Show by editor of radio merchandising by C H WARD articles to help the beginner in radio ire are appearing in countless numbers la in the radio publications newspaper newspapers and elsewhere and rightly so to for the number of newcomers comers in the art Is legion there are also discus alone of the niceties tle theories orles of operation and an more or less ess complicated and unique layouts of apparatus for the advanced amateur the fellow who has the inclination time and apparatus to ro go into the theory of t radio for its own sake bake and te to help in the development of the art personally I 1 feel that I 1 belong to neither class din and hare have often heard the same saine comment from other amateurs the experienced amateur let lot me speak for these other fellows when I 1 sly oil that we understand the principles involved in a practical way that we guilly want te to have a hand ta the construct construction lon and installation instillation of our apparatus and that we hare have the habit of changing our apparatus and circuits for better or for te to the intense lis pleasure of our listening family filmily and aid friends foremost ost in our minds though are rood pod results we find it necessary euary to know the theory of radio but we are more interested in the doing than in the knowing if our radio experience becan begin before the war its history Is probably about as follows up to the introduction of phone broadcast loose coupler and crystal loose coupler and budion A tickler book hookup no using the old cou coupler or honeycomb colls finally the climax Is 13 a short wave set the latter seems like an on in definite term but to the amateurs of it PY 14 A me y this regenerative hook hookup up Is very efficient and li Is particularly useful for the longer wave length abort short time ago it could only mean one thing a regenerative set consisting of three tuned circuits using a let er and two vario meters when broadcasting was young it we were to carry our history a little way into the future it would probably have something to do with a radio frequency amplifying system and a loop aerial however most of us still look on that short wave set with awe for we dashes from low power tar far distant stations that other radio but buts could only hear bear in their imaginations and when broadcast broadcasting int started there were rights when it seemed that the pr program was in the same room and the sound details of the announcers voice were almost uncanny one could bear hear him draw bis his breath and make the other little noises incident to speech that remind us of the wonderful cepro duct lons of harry landees La aders voice on the phonograph but unfortunately there were nights when programs did not measure up in anne quality to r n the cheapest phonon ab ly IT when our friends dropped la in to listen for aa an evening tea yes there have been nights when even the sound of a voice 1 of any kind would have been welcome our ears am and others when signals started to wine swing and our nerre nerves were a so shattered trying to keep in tune that we swung up and copied navy press lut just to be lure sure ot of something to make batter matters more embarrassing possibly we topped stopped in to hear bear the neighbor ge betone one of the th new broadcasting re ceibert ce ivert 1 IR immaculate little thing ehlt with tire two knobs to play with and nd possibly a mt set of dry actus to light its fill merit and nd behold ve we beard the whole concert through nih of course the tone tolle quality in the same dass class ai 93 that from oar our three circuit set when it decides to perform but still we hare bare to band hind it to oar our neighbor for he be always gets something and sometimes we WO get nothing personal awin here on I 1 must stick to personal bonal experienced eL possibly they will be repetitions of other fel fellows lowie experience but they may help others to let get the results I 1 am getting now good regula when I 1 saw my neighbors set and find others tike like it I 1 at first decided that the refinements introduced in large scale wile manufacture of receiving 11 seta sets for concert reception made blat a set I that could not be duplicated by the home workshop except by chance and land we should all te remember member that this Is true ne no matter how bow rood good oar our results may be later however when I 1 found the boys turning out cut one and two dr l colt cult ets gets that performed almost as well as ones oum and 5 some 56 6 of them very crude ends in IA it to beup be up to me to junk the old abort wair wave set and build something aga while planning the new set it occurred burred to me that all ill such seta ego differed from bom the conventional I 1 tuner toner la in having a direct InduCt ITS couplin between the plate and rud grid rid circuit in ether other respect respects they varied widely and ad it wu to elat the best 1 arrangement I 1 never did decide which one to build but instead ottem my circuit I 1 complicated it 11 it Is hardly necessary nece to state that tone tons quality selectivity and relief from static are attained to a greater doreo free with tareo tuned cIr circuit than thin with the simpler arrangements and the addition of gatins tatins mean for coupling the crid grid and plate circuit circuits provides pro Tlde ata and ease la in tuning which are sometimes difficult to obtain in the conventional three circuit tuner of coune course considerably more time Is coo con amed fumed in tuning the three circuit let set when first put in operation but this hai his never been a serious matter if re suits could later be b duplicated using the lame same adjustment for the same sta ta atlon his been found possible with the sot et stabilized by direct feedback coupling while in the ordinary three circuit tuner adjustments for rood good phone reception vary dally daily early MIth methods the first means of coupling which was w devised consisted la in splitting op up the plate varl ometer stator winding into two halves baitel on one halt half was left la ia the plate circuit and the other con eon necked in aerie series with the secondary of the varlo coupler and tid grid vart ometer the operation of the set et connected la III thil this way proved that the coupling pro tided tied waa was a decided stabilizer or in other word that tb the idea was good stations were toned tuned in with practically the same adjustments day after day the set et remained in operation without further adjustment tor for as long ae its desired ired and find the tone tons quality was equal to the beat best remit results obtained with the usual connections two of the broadcasting stations regularly heard however and many fA familiar millar amateur stations could not be heard beard these stations were all broucht back by chanting changing to the arrangement ran gement shown in the accompanying diagram where a separate coupler la Is used for grid plate coupling and the plate varl ometer left intact the coupler used was made up on the common varlo coupler forms with 80 30 turns of no 22 cotton covered wire on both stator and rotor the stator Is in the crid grid circuit and the rotor in series with the plate Tari ometer I 1 consider the set the last word in recen receivers 1 barring the renne refine ments merits in design and manufacture that could well be introduced and I 1 believe othera others will find it so until they are able to bid old man static farewell with a loop and IL F amplifiers the tile coupler used in this set Is 3 inches in diameter and the stator la is four our inches long but it ll 11 obvious that slight change changes in and wind ing will not affect the results obtained as its both circuit circuits concerned are ael aap arabell tuned Q U radio HW shunting wave of bothersome neighbor the owner of a receiving bet set was bothered by a neighbor who broad cast on 20 meters but owing to close proximity would overlap BW meter wave waves A solution of the motter was worked out ai as shown on dla ram gram the principle li Is to shunt mm him out take for example a SW meter broadcast everything Is going along beautifully when buzz buzz CIC etc P comes in to spoil it all OIL he Is ji sending tending on a 20 meter ware wily length but due to close proximity he overlaps the length this Is to overcome by tapping tipping off from the antenna to a single circuit tuner consisting of a variable con eon 11 auxiliary tuner shunt shunts denser and tipped tapped inductance coll in eries series this Is 1 ran to the met plate aide side of the phone condenser from the other aide of the fixed con COU denser yon you rna run to ground when this auxiliary toner tuner lj Is tuned to his wave length the vibration be lie li Is sending win will travel over the hunt shunt circuit to the th ground and as they thel an IN hot riot audibly transformed in the delector detector d bulb you will not bear them under ader certain condit condition lous and aud with proper ao tun toner it italic C can be b eliminated reflex amplifier A reflex ex amplifier using three a cryetial detector aad and asio dated apparatus appa ratu may way bo be ft lb connected As a to provide three stages of radio frequency amplification detection and two stages of radio frequency amplification no tubes thoi thus operate both as radio and audio frequency amplifier bat but it la is not to to attempt the ur use of mors than two log fifee of audio frequency bency amplifications due dub to the fact fact that the highly audio frequency francy signal presenta pre renta the tube tubes from efficiently as radio tn tro quency AMPIl dL |