| Show GREAT DISCOVERY OF EDWIN H ARMSTRONG arrangement by which local plate current Is fed back to grill grid I 1 circuit an AD ordinary three electrode welin star who tube used as st detector in a 9 ell cir salt where the he input to 1 connected to the U crid rid and it t the h a output takes taken from th lb plot platt t will tit give loa lam of from 6 to 15 25 adding to this chi amplifying se action an uie the stability liability of slumbered of the he tube gave the tube reference the crystal detector listed ignal ill point la readied ha where the fed back tha from bic tin the ill plate is circuit Is just equal al t to Q ui louei I 1 la the td circuit oil S an m anew le la in the me coupling between M the two mo coils calla M and N will cause the tube to excillie by hung ing the main tuning g of the sec ae condary circuit cirg it the few ivary of ill ih tube ocal c haders will be slightly different dit ferent tr troia in the frequency of the lu inclining salm odal ell ill lablona due to the received signals old and the me be bent I 1 note will be heard 1 in the phones T the b apitsch pitch of uie the tat kerat n note are aal be mo arithmetic difference between tile frequency of the inconis ins 1 ar illation and the oscillations fugal furnished shed by rho detector tube tub th abe home ear or Is 1 most let sensitive to a note corresponding to 1 3 01 amt amra b eions per becom secom second or stridently electrically to note to produced b by y wo cyl cycled US supplee up betho the re received celled signal was on an a meter Z wave length of 1 by adjusting it alie a circuits ao an that me tube tub would osculate late at a frequency of I 1 T 7 Ro however llover it wax not until edwin 11 armstrong mathis mao his great discovery of a circuit us which fed back a port portion las of the large laree intal plate current cereals into the circuit through which the incoming signals arrived thereby greatly mp I 1 the strength of tile the signal asat the tha vacuum tube reached its row now position of duparl art alty y a a detector of radio signals the cl circuit ault arnan arrangement gement by which bonter haerry f from the plate circuit elmunt ot at a thre electrode vacuum tube Is fed bade to the grid id circuit Is known by a tome flame tho though ou on ace account tint nugh of the different names u used salt old and the different dwell circuit a arrangements ants used to Z i malish the am same results it matters amateurs iral very tery star apt to his become became confused some of the given to the circuits which fired feed energy from flow the plate circuit to tile the grid circuit are am fe feed back regenerative camast plate and ultra uhre audion 1 la fie 11 Is P 1 bbown hea th three abs elec aroda bareal vacuum Us tube with an al alternator tessia an alternating difference an I 1 of at potential to the grid circuit Z t TT T T the plate circuit of the tube cie la connected lo 10 a circuit containing an inductance or ce L and a capacity 0 end which ell together form farm a tuned tilled circuit bet between call the point X and it X Y by ad ousting the of the variable con can denser dealer C 3 the ra natural turid period of the that circuit essit between X and it Y con can be frado made to b have a the so same frequency y electra slid atun eq reat call cally so a the me alternating cu current r supplied to the grid at TT by the me alt alter notor when this condition Is 1 reached the tuned circuit between the points X and Y becomes SO an infinite inductance an in the external plate circuit T thi he P potential to atiat wela variations rions between states X and ad Y are now new a maximum and see are exact am antill lined ned reproductions reproduction of tile the poten mhd variations applied to tile slid grid th cir call by the alternator 0 going 19 halt bade to the simple sells of atinay rd t goow coupler hookup for a vacuum tube a will haw hae a circuit arrangement a as shown in fig G sup pose that the principle of tile the circuit of in fig 9 F to be applied to the circuit ar ang t of fig 19 G the result will lb be 0 fig H in pig IR tile the induct inductance urns M has been placed in 11 tile the ec condary alary circuit and the inductance N has been placed in fis the plate circuit when ties the c colls Is ill and N P are am widely separated tig g H is tiny the wasai aade do aa pig G A an incoming radio listed impressed Impress ser eo a small it difference of potential on ill the grid of the tube to in pig fig H which h els ito la turn fib learst a large beeps amount mat erit of moray energy tit in tile the plate circuit ax As ill the rall coil N I 1 la brought nearer or the acol 1 M as some an of list tills plate circuit ener ease gy Is ie transferred I 1 c to the on grid circuit this win reinforcement f or cement elect r I 1 cully of the signal by energy 1 from the plans circuit to the slid grid a cir code by the coupling beaw between u the m two call coils M and ad N causes an increase in ithe energy liberated in un alie plate clr cult it coupling the two mile colls ill sea anil is ell cioper I 1 and ad alson will cause a US great we r and creater of the ibe 1 in BOO ODO or 1499 the best note would be cycle pitch or as a 1000 vibration dote are this bent beat method of reception is used to receive or contle bondin units wase nave signals and 1 Is called the heterodyne method when the same tube 1 Is used to perform the functions of a detector said and an oscillator the method is i termed the antodino ant odine method |
