Show 1 ditoh 7 by I 1 Io boull ull airdrop ar drop editor of leall 11 1 oy W M HENDERSON I 1 ver nullo rudio fin fan lii in ell 11 a with willi the ho 4 m ten leniar y of af the three t Is c tube it lot I 1 hir rip i gon iirma PrIll ly known tint flat tile h of the kent tiny ute tute art the lie frulla of the filament und find list hr talut of if 11 e vacuum two 1111 have tousled bauix d wany rudio radio inventors venton In to attempt the tile design of if nome form of rectifying end slid to take ink the tile place of tile tub tube the result results obtained through lire tire I 1 less rexf arch nn I 1 deniges 11 bove i 1 I n na milt h to aurther del i n lable rudio n and rocel ill n on c if f the annat interesting of litiff II 11 w apell mento li Is tin tile tine to nf if I 1 replace the he vo vacuum cutini all I 1 ID ili if 11 lubi I 1 II 11 I 1 ouch ough thin f fi rm of tills 1 r wid A ml lifler in 1 n nt t dali it i W I 1 f I 1 to fit un an pih ill 1 lent ant 1 it nifty 1 nf aft f r be bp u simple IKI li of if hou how if rol col lold told solution UN off a device will A ill bf be given to acquaint rudio radio fun fatin ith the flip new development find alno also lince inre before who ho urn are inclined a working knowledge of it rol col kid told tulie tube an 0 o they may ith it if they iio so deggin the tile heart and of fill chiw tube in 1 a colloid chose 1 lioi who have studied chemistry know that flint a coll id ili Is I 1 it compound when blared 1 in l a liquid aboor bill that liquid almicar t a sponge and the of the rol col a 1 lold ld are held in by ill alir 11 glass U tub tube apparatus for making the test quid when the liquid Is driven off from the colloid by evaporation oration one of two thine things will occur either elther the colloid will become a hard olid solid mae mass incapable of absorbing reabsorbing rc a liquid or will become a solid again capable of reabsorbing a liquid colloid classification colloids Coll olda of the former claw class are called irreversible and when solidified after once absorbing a liquid are in a coagulated state colloids of the int lut ter class are called reversible this sui suspension au pension of colloid particles la in a liquid Is commonly called a col eat foldal liquid and a solution though neither of these Is absolutely correct they are now commonly used and will be in till tills article colloids generally form solution called a sol that Is whatever liquid a colloid Is placed in has sol placed after it to name the solution as an example alcohol plus a colloid equals when a colloid Is placed in a liquid the result Is a it perfect fluid auld but not as a rule transparent colloids are divided into two classes emul solda and th the when placed in water have the nater matter penetrate their parti cles cle while the are those colloids which are not penetrated b bi the liquid thus particles of suspended colloids will be in a state of huspen ion slon in the liquid are most ly organic ancee white while anipen bolds are metals sulphur selenium etc the latter are the ones used in radio work if it a colloid solution be under a powerful and sensitive microscope it will be noticed that there Is a D fig 2 glasa jar two electrodes ard colloid solution necessary constant movement of the particles in the liquid this movement Is I 1 given two explanations one Is that each particle of the colloid has a charge of electricity and each particle la Is charged at the ame same polarity consequently there Is to a constant repulsion between particle which bich would cause the movement noticed tinder under the microscope the second theory Is I 1 that the liquid molecules are constantly striking the colloid particles the impact bet between ten the molecules and particles gives the noticed particle movement mo emeaL how tt test can be made no matter which may be the real cause of this movement and either may way be wrong still it III 1 acceded that it Is this particle movement which gives a colloid solution its rectifying and amplify log properties A test of this can be made by using the top p par shown in rig FIL I 1 A glass U tube a colloid distilled water uster and two platinum or aluminum electrodes are necessary tec essary 8 these colloids oll olds may be pro cured to in most drug apply supply hou house sest with the apparatus appa ratu mounted as shown in the diagram and a source of high potential current connected to the correct lead leads a concentration et of parti ten 1 round around of i pie ir iral to will lie 1 party curl allm I 1 ty Y if tic in ili rest rol I 1 flint eh fl fro rn ir to hers a roll III s i luil n li is tn to I 1 IP P cm orn I 1 lo 10 lol t 1 I UN an a rc lifler f rn ho it IN 11 off ghan in HK hg 1 A glass jar two des fill I 1 if colloid n sire Mcc A lion ha four tinion flip ati face of A this rectifier fun I 1 P led tell in it radio raf elsing 1 ewt I in I 1 isire f if f it f r elal 4 d feet leahr r the pigs lit ON from froin iti all if ali ill vi will ill III ra d gr Pitter lhnn ah kith sin arntal 1 11 V fan OR le re r elid 11 on tills 1 fit 1 1 4 I 1 r ith nt fit it hi ill I 1 f nn tin 4 eternal 3 I 1 the this type of tube may be B died used as i an oscillator or a ticker I 1 lor or t pat re ro nulls the inith of A must be arld tile action of this detector however rapidly bc meaer an nt at the end of two or three h urn urs becomes in 4 pera operative tive fill it activity may be renewed ho however weier if the connections or are a re A constant of con sections will keep the detector in action for some time used ai as in an oscillator slight success hits been obtained bj by using this type of tube as an osell lator in the circuit hown shown in fig 3 here a control electrode similar to the grid of a vacuum tube Is inter posed between A and B reversal Ile ot of polarity also materially increases the th life of the owilla oscillator tor two circuits for ui ing the tube ai as an emp lifler are riven given the first li Is for a dimple simple two electrode tube this operates in the follow following ing manner an alternating current lowing flowing through the input circuit causes onuses a variation of resistance which Is of course proportional to the potential variations because of the neg negative negal alive lve characters ls ties tics of the tube a reinforcement of 0 the alternating circuit Is obtained in III the output circuit for the amplifier circuit connecting a it tube 1 I luia a control electrode the ai 00 SW 13 4 A figa 8 the th action Is ili different for amplifier circuit action Is different the variations in the applied alternating current force the control electrode to art act elect icalla upon the flow of colloid particle particles A and B with alth a con consequent sequent slightly amplified current flowing in to the output circuit new ew 1 lork ork herald I 1 tribune vernier potentiometer will give satisfaction hen using q a potentiometer in a radio frequency circuit great difficulty Is sometimes experienced in bringing in weak stations without having the tile tubes spill split ott oer this Is especially the case with the usual vire ire wound ment as the variation Is not een but consists of small jumps as each turn of alre ire Is passed it Is obvious that a vernier attachment cannot be used US on the potentiometer itself us as it 1 Is IV im possible to get any tiny variation between turns the solution Is to employ a variable resistance reste tance of low value in cries series with the potentiometer this can eon take the form nf of a M 30 ohm rheostat if it the t potentiometer has a resistance si of ohms it ill readily be seen that as a complete turn must be made on each instrument to vary tory the complete resistance resl siance a ratio of ten to I 1 4 thirty ohm rheostat mikes makes vernier for the potentiometer one out will be bad had men bm using thil rheostat it should be placed in series with the potentiometer and the nega neta the tle lead of the A battery in operating this vernier the movable arm should be placed about on the rente of the resistance now when as ant aln an adjustment ai as can be had Is obtained with the th potentiometer a very fine one vernier effect can be made with the rhe rheostat M attachment may be used with any radio frequency dwelt er and will prove extremely useful on 01 loay long distance stations Badio beira |