Show A N iz r the wiring diagram for five tube radio frequency receiver by rdward EDWARD SPIEGLER in nw new york harald tribune for a dependable trustworthy ruddo broi denst receiver one that will work consistently night in and night out without fuss or of bother the writer believes it ta is difficult to find one more desirable than a straight five tube three dial tuned radio dudlo frequency set constructed with eff lelent condensers conden sira and tuning tun log colls coils and equipped with standard accessories the sensitiveness selectivity and volume of tin nn outfit of this type can be guaranteed lu in advance arid and tile alie builder can be assured that lie he la Is riot not spending ills his money on some bonie ones notion of a freakishly different re celver of worth when lie he lina has finished the wiring and con coil needed the batteries lie he will henr hear bronde anti and hear it well 1 tile he writer recently completed such a receiver incorporating in it the lie acceptable innovation of a few now new tuning inductances and enjoyed nn fin instent satisfaction front from it that was 3 unusual mial lie ile had previously madr mado a number lumber of popularly exploited exploit pl talio indio frequency sets of dir different forent disi des izil n lind bud spent whole evenings of patient on ench each in ili an to good results this orthodox d unpretentious bow boasting sting nothing n illi more radical than some straight line frequency fie quency condensers conden sert an ill lif Terent bent R r F colls coils produced such results in ili the lie form of 11 aminy in and nd loud load stations that hint lie iwo K 0 pie who want foolproof fool proof rece hers should li bo be tod old about it parts required the overage constructor line irive no do in tile lip ret the lit nad of if ordinary hand riols ill hip I 1 arts required me are ri it panel 7 I 1 fly 21 inches of any rood mn terdal a half inch thick wood haap bofird of the sanie same dimensions three gen win I 1 colls three 0 enfil straight line frequency cond ns ers three dials dents to fit sume same one sir BIT and one thirty ohm rheostat ono double and one single circuit telephone jack the standard tube grid condenser and leak two audio fr fre quency transformers one line battery switch one binding post strip anti the usual bulbar oil and other incidentals tile the set Is most conveniently as in two units the panel and the baseboard liase board the sockets for the it II F tubes oc cupy the space between th the variable condensers and a little to the rear 0 of them the detector socket Is up in the extreme upper right corner of the baseboard and Is followed by the A F transformers B and tubes winding along tile the back edge of the board the second A F tube la Is in the upper left section its 1 I P post going convenient ly to the telephone jack in the lower left corner of the panel similarly the right hand jack connects to the nd ad jacent detector socket this U shaped layout lay out keeps all the connections very short and in their logical order about 00 90 per cent of the wiring in evolved in the lie construction of ills receiver con can and should be b done on the baseboard instruments before tile the panel la Is screwed into position the constructor Is advised against assembling r sem en bling ibling tile the parts flygt and wiring afterward as tile lie pr presence esene of the protruding variable condensers will make the installation of ninny many of the wires exceedingly difficult no binding posts ore are provided for the C battery as tills this unit Is most easily connected by means of short lengths of flexible cord the other battery connections are standard and are easily followed the wiring the wiring of the it F and A F V sieges Is 19 more or less orthodox in nature the three variable condensers are connected directly across the respective s spec tive of the Ler nials colts colls with stationary plates going to the grids of the tubes and rotary plates to the filament cir circuit cult the feature of this receiver outside of its ita ge general effectiveness Is the type 0 of f radio frequency tuning units employed each one consists of a 15 turn primary and a turn secondary the wire being wound according to the principle TI this 1 I 1 form confines the electromagnetic ife fi field alsid and idill neutralizes the tendency toward osell batlan the extraordinary length of tile the lenini curve reduces the resistance si othera otherwise ise encountered la in small diameter colls coils the wire used Is no NN 20 enameled high turn to turn capacity being avoided by a system of spaced wind ing over oil all it a coll Is just three inches long and two and three quarters across tile loops tile tho small diameter of the latter Is one inch an ingenious experimenter can readily rig up a winding jig made of two short curtain polo sections nailed on oil end of a board and produce do hirable colli coils tile the directions which the magnetic flux of each section of these culls coils us as by 13 virtue of tile tho peculiar wind IM lug ing lucheme are such that the colls coils ni n 3 units linio have completely Colin lINI ning betic holds fields tills this pro propero proper perv tv precludes the necessity of mounting the colli coils at particular angles in ili a receiver in ili order older to prevent hier coupling the absence of interaction also gives aall coll coil a fixed and definite induct talice nue balue tile lust last mentioned fiut fact Is 19 depond llo ble for it 11 very eit desi desirable roble effect namely the lip alino almost t ex exact rt vo of the three viii bablo condenser roid rend ings ins front from aw right ui tu to 0 DIl Terent merlill nc lal lengthy see hoem I 1 to have m intile li IK r on nil the first con co it denaer the n variation nt at thre hopr dil Terent baing not I 1 I 1 inina in one point on n it i 1001 1 milt 1 to select lait oral I 1 DX onti ils f hixt ahe nax in til ilin liIng liK two tuo tu o of hie file dint rending nu dinKS 4 were TO 71 hiir beach fill I 1 IK als N 1 I 69 for NGY C schenectady iiii lind 8 1 SI st SO for fir VII ir it I 1 li actually in poi i iss isello Ahle llo to beill it II slit ln on oil vall aili 1111 selling of tho wine hannel allocations rind of file line frequency character isic of the lie receiver ian her |